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Kohler CV20 too much oil in the engine. Gas?

10K views 51 replies 10 participants last post by  Ericjr16 
#1 ·
Need help figuring this one out.
Craftsman GT 917.251522 w/ Hydro
Kohler CV20s, 20.5 hp V twin.

Put the snowblower on in late Nov. Did all the stuff I usually do to get ready for winter.
Did not change oil as I just changed it in July, and was not using it for mowing. Did check the level though.
Mostly hauling fire wood, and picking up leaves with the bagger.
Figured I would change it out to 5W-30 once it got cold in Jan. Cold came early this year.

Parked the tractor in the unheated shed. In the fall and winter I have a routine of driving for 10 min before parking so I am sure engine gets hot enough. I've had moisture build up problems in the winter with this engine in the past.

It snowed last week. Went to start it and had to crank it several times to get it to start.
Engine hard to start, was -10° F over night. Outside temp about -4° F when starting engine. Starter turned it over just fine. A little slow because of the cold, but seemed OK.
Usually starts after 5 or 6 revs. even when this cold. Turned over many times with full choke.
Gave the starter a 30 sec break between tries. 10 Sec on, 30 sec off.
Finally started. Had to keep choke partly closed.
Let clutch out and it died. Started right away but had to keep partially choked.
Lots of white smoke or water vapor, hard to tell which. After about 1 min it ran w/o any choke. Started forward and almost died. Had to quickly pull choke knob. Moved outside and no smoke. I checked the choke butterfly later and it closes completely as it should.

Did some snow blowing and engine just did not sound right. Had power, but not the usual twin engine sound.
Note: I broke 4 shear pins on the impeller. On 4" of dry powder? All in a half hour. Knew I had a problem.
I'll start another thread on that. Problem right now is the engine.

Put tractor in the heated garage to find out what was up with the shear pins.
Waited until next day to look at it. Thought about the hard start problem and thought maybe gas was draining back and it took awhile to get fuel pumped into carb. Taking stuff off to get to fuel line on carb, I found oil on the air filter gasket and a little on the adapter plate.
Found water in the spit cup, oil breather tube, and the oil breather. Lots of water. 3 tablespoons or so.
So that tells me stuff was froze up when I was trying to start it.
The line at the carb was full of gas. So lines were not back draining.

Then I checked oil. Oil was 3/4" above full mark! But did not smell like gas. Really.
Had to measure 4 times to convince myself it was that high.
Measured resting cap on tube.

Drain oil into a coffee can. Measured it and had 84 oz. Suppose to have 64 oz at most.
20 oz over full.
I had the wife come out and smell the oil also. She did not smell gas. And believe me, she can small gas in the house if I spill just a little in the garage.
No sign of water in the oil. Some white goo under the valve covers. Very small amounts.

Fuel tank in this thing is below the carb.

What is up?
Am I in denial about smelling gas?
Took a whiff of the jug I stored that oil in today and still no gas smell.
But the only other liquid in the system is gas. It has to be gas running into the crankcase.
If it were water (That's a lot of moisture) it would not mix with the oil.

Could frozen water in the carb and breather have pulled gas into the crank case while working it that day?

Removed anti backfire solenoid and tested with a battery. Working, but snaps back slower than the ones on a B&S engine. Fuel bowl was full of gas. No water in bowl.
That smelled like gas!


Changed oil filter. No gas smell there either. Have not added new oil yet.

Want to see if gas flows into crankcase over night.
Rigged up a small gas tank about a foot above the carb. to gravity feed the input on the carb.
Ran the line to the input on the carb. Checked and had gas flow to the carb inlet. No leaks.
Left the carb not tightened down to see if gas came out the rear of the carb.

Put 12V battery power to the solenoid for about a half hour. No leaks.
Left the tank hooked up for about 3 hours and no leaks at the carb.
Put the adapter plate and spit cup back on and tightened the nuts.
Left it like that over night tonight. Will see what the morning brings.

Anyone have any ideas what caused it?
I know I did not add 20 oz of oil to engine before I put it away. No one else has been here that might have added oil.
Wish I would have checked oil level before starting that time, but I did not.
 
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#2 ·
Have not been out to the shop yet this morning.
Thinking about this just now, I wonder if the frozen water in the spit cup / carb may have been keeping the choke open when I first tried to start it?
I did not check when I first brought it inside because I was not suspecting moisture problems again. I was sure that by driving it around for a bit before letting it sit would get the engine hot enough to boil off the water.

To help with the moisture problem I have a baffle on one of the upper triangular air intake ports as Kohler recommends. It closes off one of them and restricts the other one just a bit.
I also installed some tin around the exhaust manifold to help bring warmed air into the bottom of the air intake. Baffle in place and Tin is outlined in white square in picture.

Auto part Vehicle Engine Carburetor Automotive engine part


Put a piece of cardboard over the air intake on the front of the hood. Put it inside the hood. A bra as it were. That seemed to solve the problem last year. I put those pieces back on this year when I attached snow blower.

Machine Electrical wiring


There is a shroud that fits between the top of the hood at the intake louvers, you can see in the picture, and fits around the top of the engine when the hood is closed. This draws all cool air from outside. I am thinking of removing that shroud for the winter. That should make engine draw air from inside the hood.

Good idea or bad?
 
#3 · (Edited)
Checked the tank and the gas level did not go down any noticeable amount.
Hard to tell if just a Tbls. or so is gone.
Opened the oil drain plug, about a Tbls. of Oil came out. Still no gas smell. Felt the oil. Seems to be thinned compared to new oil.

Engine Kohler Command: CV20S-Spec No: 65530 V Twin

I want to check the float and clean the float needle and seat.

Can I do it w/o removing the carb?

Looks like I remove the solenoid and wiggle the bowl and it drops down. Is that the case?

Diagram Auto part



I do not see any little screws holding the float hinge pin in place. Is that the case?
Will the float drop out with the bowl?
 
#5 ·
Thank you Roger.

I have the float bowl off.
May have to take carb off. Was trying to avoid that. Always looking for an easier softer way.

I could not force the pin out of the holder. Pushed only so hard then decided I better back off before I break something pushing at that angle.
Is this suppose to slide out easy? Or is it held in by pressure fit?

Auto part Machine tool Machine Engine Toolroom


It is a Nikki carb. Have to see if I can find any numbers on it.

Be nice if I could clean the end of the float pin and the orifice it closes. Then put back together.
But, may have to remove the carb and linkage. I have the tech book for what it is worth. Says to remove the carb and the linkage as a unit, but does not say where to detach the linkage as a unit. I will try to remove the nut that holds all the linkage on at the pivot point.

Having to take lots of pictures and notes as I go. Carbs were never my strong point.

BTW: Had the furnace tech out today to work on house furnace. Had him smell the oil in the coffee can I drained out this morning.
He said he could smell gas. Not strong, but enough he knew gas had been in the can.
My sniffer must be getting bad.
 
#8 ·
I found the nut I was referring to is more of a adjustment nut to tighten and loosen where all the linkage levers pivot.
Don't have a picture right now.

I can disconnect the throttle linkage with the plastic parts. But the rod that moves the choke is not coming off too easy. Rod is very hard steel and will not let me bend the hook out of it. Probably not the way to go anyway.

Will have to get at it in the morning. Wife wants to go shopping tonight.

I will try more pushing on the hinge pin tomorrow first. Want to try and clean up float and inlet valve to keep gas from running into carb and down in to the engine.
 
#9 ·
When I get one with fuel in crankcase I replace needle AND seat when it's replaceable. The ones that aren't I polish with Q-Tip in drill with fine valve lapping compound. Then finish with metal polish like brasso or flitz then clean with carb cleaner and fresh Q-Tip, then blow out with compressed air. Then just replace the needle as they are usually available.
 
#10 ·
Got the carb off. Cleaned and back together tonight. Will post more tomorrow. Time to hit the hay.
 
#11 ·
Finally got out in the shop late last night.

Decided to brush off the dirt around the top of the float bowl. Clean it up before I started working from underneath again. Small steel brush, some purple power. and a rag. Working away at it and pulled the carb forward. Carb fell off the studs into my hand and the choke linkage fell off. No idea why it would not move all the way off the studs before. It seemed no matter how I moved it, the choke linkage kept it back.
Glad I took a lot of pictures.

Have the carb off. One problem solved.
Used purple power and a brush to clean the outside. Compressed air.

Auto part Carburetor Automotive engine part Engine


Float pin did have a flat spot on one end. Had to push from rear of carb to force it out.
Came out the front, so reinstalled that direction.
Used a wooden dowel to push on it. Took quite a bit of force. Came out with a pop.

Auto part


Carb cleaner spayed inside and through. Small wire in all the holes, more air.
Clean again, and so on.

I was loath to remove the metal cover and gasket from the low idle mix chamber.
Gasket was really stuck on there. Exacto knife did a fair job. Got most of the gasket off.
Used a little RTV brushed on with a toothpick where I thought I needed it. Hope that will be enough.
Auto part Carburetor Automotive engine part



It is a NIKKI carb. #621028-461

Auto part Metal


Needle seat not replaceable. Did clean and polish as TobyU suggested. Did not have any metal polish here. Wonder where my can of Brasso went?
Auto part Automotive engine part Carburetor Rotor Tool accessory


I can see a ring on the rubber needle tip where it rode in the seat. So will have to order a float needle. Hope it will run for now.
Brass Metal


But meanwhile maybe I will have a running tractor.

Cleaned and ready to go back on.
Auto part Carburetor Automotive engine part Automotive starter motor Automotive super charger part
Auto part Carburetor Automotive engine part Automotive starter motor Automotive super charger part


Have the carb back on. Upper Air baffle in place so more warmed air will be drawn into the carb.
Auto part Motor vehicle Carburetor Engine Automotive engine part


Tin heat baffle in place. So warmer air will be drawn into lower part of air cleaner.
Auto part Engine Vehicle Metal


Refilled with fresh 5W-30. Took my No Oil sign off the dash.
Auto part Shoe Machine Wheel Vehicle


Found this site after I came in for the night.
Looked up the Nikki carb number.
Good pictures and how to clean the carb. Little different carb but good pictures.
Disassembly, Cleaning and Repair of Kohler Command V-twin Nikki Carburetor

Installed a inline fuel shut off. But had to mount it back about where the clutch pedal is. Between the tank and just before the fuel filter. It is at the lowest dip in the line. Hope it will work. Or I may have to go to an electric shutoff.
When the snow blower is on, I would have to take the hood off completely in order to reach one mounted up by the carb.

Will order a kit with the needle today and hope I get by until the parts come in.

I'll head out this morning to see if it will fire up.

At least now that I have done it once, should go fairly quickly when I get the new parts in.
 
#12 ·
JP, my dad needs to pull the carb off our other GT with same engine. It has high speed stumble at times. You look like your getting it done! Sorry I just saw the link as my phone left it off the page when I looked there! :(
 
#13 ·
Got out late today.
Life gets in the way sometimes.
I fixed the furnace the other day. Failed again and had the furnace guy out. He did what I did, cleaned the flame sensor. Found out can not buy them anymore. NLA, where have I heard that before? Then today it failed again. AND the heat exchanger fell apart. Those are NLA also. Mine just hit 20 years old. Had to order a new furnace. There goes $4,500.00 I was not counting on.
They wanted $300.00 extra to get it installed before Christmas. Nope, ain't gonna go there. Got the wood stove fired up and it is fine in here. Weather looks like it will hold til next week. So as long as temp stays above 10° F, we'll be good with just the wood heat. Even if it gets colder we can keep it warm in here, just takes more work to keep the fire box full.

Neutral / park safety switch went out on the Pickup yesterday. Changed that today in the wet snow. Yuck. Not a hard job, but a hassle.
What next? Does this make 3 now so the run is over?

So when I finally got out to the work shop I double checked all I did again. Oil was a little lower, added 2 oz.
Noticed a quirk today. If I put the dip stick in with full mark pointing out, away from engine, shows full, and back of stick shows low. Put stick in with the Full mark towards engine, shows low at full mark, reads full on back of stick.
I will have to keep that in mind.

Left the hood off, Put the front on the snow cab. Put the shoe boxes back on.
Motor vehicle Engine Auto part Vehicle Car




Opened the new shut off valve. (That will take some getting use to.)

Auto part Fuel line Engine Automotive fuel system Vehicle



Opened the garage door and fired it up. Counted to 10 and just as I turned off the key, she fired and ran fine.
Some oil I dripped on the muffler burned off. But no smoke other than that.

Drove it out and let it warm a little.
Pulled off LH plug wire, governor snorted, but it ran. Ah HA! That was what it sounded like the other day.
Put LH wire back on and went around and pulled the RH wire off, governor snorted, and it ran. Put the wire back on.

Backed it back into garage. Turned of the engine. Had throttle too low, and had a small backfire. Just a puff.

Checked Oil, added 4 oz. That made 64 oz total.

Put the hood back on and went out to try the blower.
Filled tank with gas.
Lowered throttle, pulled on PTO. All was well.

We had 4" of powder before when I was snapping impeller shear pins, since added 2" more.
Now temps warmed and all turned to heavy wet mush. Blew snow for about an hour to clean what I missed before. Never popped a pin. Engine ran strong and the blower really threw snow.

If the engine was only running on one cly, why would that cause so many broken impeller shear pins? Anybody?

The other day when I changed the plugs I noticed they looked black and oily. Did not think they looked too bad. Didn't pay a whole lot of attention. Checked them again today and found they were in pretty tough shape.
After hearing that engine run when I was pulling plug wires, I am thinking now one side was not firing last time out.

Could running on one cly for an hour load up 20 oz of gas in the oil?:dunno:

I have a habit of filling the fuel tank before putting tractor away until the next storm. I think if tank was full, top level would be higher than the carb. So may have been dirty or leaking needle. :dunno:

Figured I would mention when I took apart the carb the low idle was out 1 and a half turns. When I put it back together I turned it 1 and a half out again. Kohler book shows to set it at 2 and a half out.

Engine running again. Still have to order a new needle.
Many thanks for the help. JP
 
#14 ·
Hey JP bet the slight pulse from non running cylinder caused the pin to have uneven loading? Also dead cylinder would still get the fuel, have to go somewhere!
 
#15 ·
Also dead cylinder would still get the fuel, have to go somewhere!
My thoughts too. Gas would have to go somewhere. Worried now as to how much damage was done to which ever cly was not firing. Being washed with gas for that long could not have been good for it.
Too much going on right now. But after Christmas is over will try a compression check and see if one cly is worse than the other.

I suspect it was the LH cly. Looking at the plugs.

It bugs me that I noticed the engine was not sounding quite right that day, but too many things on my mind and I did not pay enough attention to it. Had to get the driveway open.

Plan on changing oil again anyway. Tempted to fill the tank, park it out in the shed, open the shut off valve, and let it sit a few days and see if I have gas in the oil again before I change it.
 
#16 ·
I have read on a tractor pulling site online that has many good tips on ignitions for small engines,that many Kohler's that used one coil with two plug wires to fire both plugs,often fail internally due to the high resistance of two plugs with .030 gaps--that in fact is like trying to fire one plug with a .060 gap..


If the plugs get a bit fouled,and they are more resistant to firing properly,the spark tends to take the path of least resistance to ground,in this case,the spark "builds up" in the coil's secondary windings,and caused them to short out to ground internally--sometimes this will only reduce the spark's intensity,other times it'll kill the spark completely..

The site says to set both plug gaps at .015 and this will reduce the load on the coil windings,and make the coil live much longer,and they say you'll likely never notice any difference in how the engine runs with the gaps set at .015 instead of .030..


This is the link to the site I read this on--you'll have to scroll through it all to find the reference I just mentioned though..http://gardentractorpullingtips.com/ignition.htm
 
#17 ·
Running on one cylinder will not put any gas in the crankcase. The only place the gas goes is out the muffler. So the exhaust ends up being far too rich and occasionally it will pop which is the backfire you are referring to as the extra fuel loads up and explodes abruptly. The only normal thing that can allow fuel to get into your Crankcase is a needle valve in the carb not shutting off properly. You should definitely put two new fresh plugs if you haven't already. I will agree that I have seen weak coils that didn't fire properly at .030 but would work fine a little bit smaller.
I would just go . 015 though. That's too small.
. 025 is better. No tighter than .022.
Also with two fresh plugs you can read them in a few hours and see if they look the same. The Kohler twins up until around 2003 our 04 and some other years had a problem with blowing head gaskets. I don't recall in your previous post if this has ever been done but I have seen many twins that as they run one cylinder will come and go and you can hear the sound difference even with no load but especially worse under load.
On those, when you pull the plugs out one is noticeably wet sooty black and fouled and the other one looks great.
That could be a problem or you can have one of the coils starting to go out. If you have not taken the shroud off and inspected you need to do so now. Any animal chew will cause the spark to jump out of the insulation every now and then or whenever it wants to and cause a misfire. If you find a wire that's not chewed at all the way through you can rtv it and tape it and it will be fine. You should also remove the Shroud every 3 or 4 years anyways just to make sure there is no grass buildup that can cause overheating and damage to the engine and rings.
 
#19 ·
I have been mulling on this myself. It seems to me some small amount would get by the rings. Problem is I am trying to account for 20 oz of gas getting into the crankcase.

Thinking it through. On the side not firing.
(1) piston goes down drawing in fuel and air. (2) Up, has compression, no spark.
(3) Piston goes down. Vacuum in the cylinder. (4) Piston rises again, exhaust valve opens and fuel and air mix is ejected into the exhaust manifold, and then into the muffler.

So now I am thinking what if a engine is firing properly? No fuel leaks into the crankcase. So even if not firing, no fuel leaks into the crankcase.
Maybe a tiny amount is getting by the rings on a cylinder that is not firing. But I am thinking it is tiny if anything.

The problem lies in the float needle not closing when engine is at rest. Really kick myself for not having checked the oil level that day before I started.

With the fuel shut off valve closed, so far no gas in the oil.

Ordered carb rebuild kit with new float and needle yesterday. Wanted to wait until after the Christmas rush.
Carb is a NIKKI 621028-461
Kohler carb part number 2405325 (Embossed on carb)


Carburetor Repair Kit Replaces Kohler: 2475706-S, 2475718-S
Carburetor Repair Kit Item: 06-1026
Replaces Kohler: 2408619, 2408622, 2408923, 24 757 05, 2475706, 2475714, 2475706-S, 2475718-S Fits models CV18-27

$22.51 with $4.50 freight That was the best deal I could find, and I have bought from them before.

Should be in this week and will go through it next weekend.
BTW, I did change plugs, they were in bad shape. Still need to do a compression test. I think the LH plug had crud on the electrode shorting it.
For now, it is running well, and as long as I close the shut off when parked, I'll get by.
 
#20 ·
No fuel will get into crankcase from not firing. No amount to notice. Esp not 29 oz. You would have to do a used oil analysis to detect increased fuel levels.
You can damage shorten line life of rings but not likely on these small engines.
Car guys used to use the expression "wash the rings away" If a cyl was not firing long enough but big v-8s put a lot more fuel through them.
It was more about washing the oil off and overheating from friction on rings and walls.
Think of it this way. Most of any extra fuel would come out the exhaust and if there was that much fuel in the cylinder you would have
liquid coating the inside of your muffler and dripping out of it until it built up enough to explode which is what the after fires are. Not really that much gas in there, more of a vapor in suspension. It only gets a plug wet because it is collected at the very top and in the cup of the spark plug.
 
#21 ·
Time for an update

Got the carb kit in Saturday. Installed parts on Monday.
Auto part Automotive engine part



Went out to the barn Sunday evening to get the tractor and bring it in the garage.
About -3° at the time.
Been sitting since Dec 30 with fuel supply shut off valve closed. Oil level was fine, no rise in oil level.

Engine was hard to start again. Tried 4 times, got it to fire once or twice. Backfired once with nice flames out the pipe. Never had backfires when starting before.
Engine would fire and turn over a few times then die. Lots of white smoke again while trying to start it. Finally fired and ran. Once it stayed running, I had to keep choke partly closed for a minute or so. Then it ran fine. Sounded like a 2 cyl should.
White smoke for 15 to 20 seconds, then it cleared. No more smoke since starting.

Drove about 15 min. to warm it up and brought into the garage.

Hard start concerned me. Use to start after 5 or 6 revs.
I thought I did a pretty good job cleaning the carb before. Maybe not.
Went through it again before installing new parts.

Swapped in new parts. Float, float needle, Low idle mix screw and spring.
All new gaskets.

Spent last evening reading through the forums to see if I could find info on damage I may have done running with all that oil in the crank case. Did not find anything relevant.

Got about 6" of snow today. Had to use the walk behind to clear in front of the garage to make a space to let the tractor sit and run. Winds came up to 40 mph, snow blowing everywhere. Lots of drifting. Suppose to get a couple inches more tomorrow morning.

Before I take it out and put it through it's paces I wanted to recheck low idle mixture setting, and do a compression check afterwards.
This evening I was able to move it outside and let it warm up for 10 minutes.
It fired right up like it normally does. But it was in a heated garage.
Checked low idle RPMs, set it at 1280 RPM.
At 1230 RPM, it wanted to sputter and die.

Adjusted the low idle mix screw.

Just for kicks I pulled one plug wire off one plug at a time. Each time the RPMs dropped a little, and it kept running.

Concerned I may have messed up running for an hour with all that gas in the oil, as soon as I brought it back inside I did a compression test while it was warm.

LH 179 RH 188

Gauge Measuring instrument Meter Auto part Tool
Gauge Measuring instrument Speedometer Meter Tool



This surprised me. Was hoping for 140-150
Kohler books says: "Compression should be at least 160 psi and should not vary more than 15% between cylinders."

Any ideas on why compression is higher than the Kohler book specs?

Also surprised the spark plugs were cool when I pulled them off. Had a glove ready to grab them with but did not need it. I still think that engine runs too cool in the winter.

May have to run it for a few hours blowing snow, then recheck it.

The new spark plugs have only been in for an hour or so of running time: But LH was sooty black, RH was also black, but porcelain was a light brown.
Left cylinder running too rich? Both too rich?

This camera I am using is terrible, it never captures the colors of anything correctly.
(I know, a poor craftsman always blames his tools. But I've spent hours with this thing )
Pictures are not too clear, but here goes.

Skin Finger Hand Nail Material property
Spark plug Automotive ignition part Auto part Automotive engine part


Spark plug Auto part Automotive ignition part Automotive engine part Screw


Plan is to take tractor and blower out tomorrow and clean everything up.
Depending on how things go I may run it in and do another compression check.

Been reading about leakdown test and the leakdown testers.
Realized today if I use parts from my compression tester, 2 gauges I have, some other parts I have around here, and pick up a couple new air couplers, I can build my own leakdown tester.
That's the next project. Need to figure out why the LH side plug seems to be worse off than the left side.
 
#22 ·
JP Savage,i just want to point out a few differences between your early command motor and my couple of years newer command motor.No backfire solenoid on carb,No black box, that had something to do with spark,and No tunnel to hood, on top of blower housing.Black box was a known problem,dont remember why.Another problem,i had some kind of white sludge up high on my dip stick,(water/oil) I then pushed snow for over an hour,then checked oil on stick .It was barely warm to touch.So im going to try blocking top vent on hood for winter use and try to get oil temp up.
 
#23 ·
Earlier post from last night. Instead of "see if I could find info on damage I may have done running with all that oil in the crank case". I meant to say "running with all that gas in the oil in the crankcase".

I get some white sludge on my dip stick also. Too much moisture in the crank case. Engine does not seem to warm up enough to get rid of the moisture when it is cold out.

I may have to remove that shroud running from the top of the engine to the hood vents. And also cover the hood vents.
Engine would then draw it's cooling air from around the warming engine.
Maybe that will allow engine to warm a few more degrees. Then reinstall the shroud for summer use.
 
#24 ·
Compression readings can vary quite a bit between gauges, the hose length and location of the Schrader valve can give a lower or higher reading.

A lot of carbon buildup will shrink the combustion chamber and raise compression as well.
 
#26 ·
A lot of carbon buildup will shrink the combustion chamber and raise compression as well.
I am wondering the same thing. Suspect there is a lot of carbon build up in this engine.
Not going to worry about it this winter. If I end up having to remove the heads, I'd rather do it in the spring or summer when I can have it sitting outside.
 
#25 ·
Those plugs don't look that bad and they often aren't exactly the same looking especially in cold temps.
The comp is fine. Gauges vary. Even though that's a good old Penske it could be off a bit. Only thing that matters is one reading vs the other.
Don't sweat the little details.
1230 vs 1280 RPM is no big deal . 1200-1300 anywhere around there is fine. It's just a slower than full cutting speed. Doesn't need to be precise. Adjust the low stop screw where it idles down and then the mixture for best speed/running.
As long as it's running good/smoothly in both cylinders just keep eye and nose on oil for fuel.
That and blown head gasket are two more common problems with those.
No need to worry about leak town tests. If the hg leaks and blows it will foul the plug with very wet sooty oily mix and that cyl will come and go as you're running it and you will hear it. Then by looking at plugs you will know which it is.
That must not be a walbro carb as most all of those have replaceable brass seat for needle valve.
The new needle helps but is not a sure fire fix for leaky needle. The brass seat gets small pits from the lousy stuff they sell us and call gasoline.
Anytime one leaks I ALWAYS replace seat if available. If not I polish it with q-tips and fine valve lapping compound then metal polish (usually with q-tip in cordless drill) then clean and dry with more q-tips.
 
#27 ·
Yes carbon can do that but not something you need to pull the heads for. Just decarbonize with water spray this spring. Then use seafoam or my preference Berryman B-12. Run half a can through then stall it and let it sit for 2 hours to loosen all. Then fire up and go water again if you want.
That will clean it up perfectly.
 
#28 ·
Checked oil, no rise in oil level.
Fired it up and backed out of garage. Needed to partially choke engine to keep it running.
Died, restart. Died, restart. What the heck did I do now? Then I remembered the fuel shut off.:duh:
As I said earlier, that is going to take some getting use to. I was so pumped up to finally get out and blow snow.
Just got 2" this morning on top of the stuff we got yesterday.

Once I had fuel shut off open, fired right up, and ran nice.
Let it run and let the metal on the snow blower cool whist I went in and put some warmer clothes on.

Blowing about 8" of dry powder, and in some places, frozen snow under it. Ran strong. Nice to see that plume of snow fly again.
But if I pushed it in the snow banks, it bogged down a bit. Governor never kicked in. Tried pushing it a few times in the older frozen snow and same thing.

Thinking about it as I finished up tonight, I remembered something.
A few posts ago (Dec-21) Toby U mentioned pulling the plug wires one at a time to see if one cly was not firing. So I tried that.
After I pulled each wire, governor would snort, raise the revs, and smooth out. Both cly were firing.

Yesterday when I tried it again, RPMs dropped each time I pulled a wire, but governor never kicked it up. Did not think about the governor not raising the revs.

I remember I had problems routing the new fuel line from the pump to the carb. It was very stiff, thicker than the one I removed, and it did not want to bend correctly right where it bends and runs behind the air cleaner adapter plate. In fact the first one I put on there rubbed badly on the adapter plate after 1/2 hour of running. Quite a bit was rubbed off where it was pinched by the adapter plate. I had to replace it.
My guess is I did something to bind up the governor linkage when I put it back together.
I'll have to pull the air filter adapter and look that all over tomorrow. Hopefully it will turn out to be simple.

But at least I have a tractor and snow blower that will move snow again.
Now I will see how tomorrow goes.
 
#30 ·
An alternative to removing the ductwork on top of the blower housing would be to tape a piece of cardboard onto the top of the hood. Cardboard will block the air flow through the slats causing the flywheel blower to get its air from under the hood. The temperature should be a bit warmer than external air. If the ducting comes close to the underside of the hood, or touches, the air will have to be drawn from the rear, under hood area.
I have a Command single without the duct, and it is very susceptible to vapor lock when mowing in the summer. I am thinking of making my own duct to help route cooler outside air to the blower.
The air coming off the cylinders and cylinder heads should be warmer, and some of it may get re-cycled back up under the hood if you block the air slots. If you really want to get the engine up to temp, closing off a bit of the blower opening will reduce air flow. How much? That is the question.
I think the air coming off the cylinders & heads would not be very warm, and likely is too much flow to allow the engine to get up to proper temp. You may be able to slide a hand under the air outlet and feel how hot it is. My bet is 'luke warm'. In summertime, the air never seems to get hot enough to be uncomfortable when I have checked, even when the fuel is boiling in the float bowl. If I remove the hood, the boil stops. The fuel line is metal from the pump on one side, and runs across the top of the engine to the carb inlet, under the shroud. I think re-cycled airflow stays under the hood, and gets the fuel too hot. The heated air blows downward onto the chassis, and I believe is just re-directed back to the blower inlet by the hood, leading to over-warmed cooling...
Just block those slots to try it out. Cardboard & tape should last for a while, even if it gets wetted by snow blowing around. Quick and easy way to check things out, and you don't have to store the duct & fasteners, and then remember to put them back after blowing season is over.
The inlet & outlet valves in the fuel pump should prevent flow that would flood the sump with liquid fuel. The pump must pump 'uphill', so the fuel would not normally flow on its own initiative. My tank is under the seat, and it will drain, barely, if I lower the outlet to just below the level of the carb inlet. It almost doesn't need a pump. I have not installed a cutoff, as I don't think it necessary. The poppet valves need something to take them off their seat, and the only thing is gravity feed pressure which is almost nothing.
tom
 
#31 ·
tomw0,

Finally a chance to use the bright lime green or the blaze orange duct tape I received for Christmas!

I had thought about closing off the top vents also.
But unsure how engine would get cooling air if I did so. The fit of that shroud is pretty tight.
Where it bolts to the hood there is very little space between hood and shroud.


Automotive exterior Hood Bumper Floor


Where it fits over the engine it fits close around the ring on the air intake. Maybe an eighth inch between the shroud and the top of the engine.

Mechanical fan Computer cooling Technology Auto part Ventilation fan
Light Auto part Automotive lighting



The cooling fins on the engine move a lot of air. A lot of air.
The air has to come from somewhere. The way this is set up, with the vents sealed off, there would be no place for the engine to draw air from.
I think that would put a strain on the engine. May even collapse the plastic shroud.

I once had the not so brilliant idea of drawing the air out of the cab, over the engine and back into the cab through my boot boxes which are open to the engine.
I made a cardboard "air scoop" with the open end running into the cab just under the windshield. Air scoop covered the whole vent and I sealed it off with anything I could find to test it with.
I fired it up and closed the door and it was like a hurricane in there! Cold air rushing past me from every little crack and crevice. Force of the air flow was sucking the cardboard down.
Could not believe the amount of air those fins can draw.

Vehicle Transport Mode of transport Car Automotive exterior


Cab has changed a lot since then and has a hard front made out of plywood. So I may try it again with just one or two louvers drawing air from the cab.

May try blocking off part of the upper air vents. 2? 3? 4?

May just remove the shroud and see what happens.

Too bad the air drawing shroud was not designed with openings or slots you could open and close.

My fuel tank is under the seat also. Had not installed a shut off valve before because I also thought it would not "drain" into the carb. #1, fuel pump should have stopped it.

Gas had to get into the crankcase some how.

Your statements have given me an idea.
Tomorrow I think I will top off the tank, then pull the fuel line off the carb and see if fuel flows at all. At least more than is in the line. I should be able to show if the pump is letting fuel through. Pump is one of the older metal ones. Probably original.
Will also pull the IN line off the pump and see where I have to lower the hose to before fuel flows out. Just have to remember to open the frizzen frazzle shut off valve.
 
#32 ·
I did remove the air cleaner adapter today and found nothing binding. Before I removed the adapter I poked and prodded the linkage and found nothing binding. All seemed to be smooth.
Cleaned things up a little. Made sure governor arm was adjusted correctly.

Backed the tractor out of garage and tried removing one spark plug wire at a time. RPMs drop a little, governor kicks it up a bit and then runs smooth.

Back in garage and put air cleaner back on. Backed the tractor out of garage and tried removing one spark plug wire at a time. RPMs drop a little, governor kicks it up a bit and runs smooth.
I think I got that fixed.

I removed the throttle and choke cables earlier today, cleaned things up and put them back. Tried moving then to where Kohler book shows they should be. Throttle upper position and choke lower. Did not work well.

Put them back where they were.
Exhaust manifold Auto part Automotive exhaust Automotive exterior Bumper



High revs are at 3800 now. Have to adjust that down tomorrow. Had it at 3600 or so before.

I did find where the governor arm bolts to the governor shaft, the governor shaft moves in and out of the block about 3/16". Seems to be a lot. Normal?

So that's all for tonight.
 
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