[BillTheTractorMan]

My hh120 Tecumseh in the ss12 has developed and oil leak. here's some of my notes.

crank bearing seal: no leak
Valve cover: pretty sure its not it, dried oil and faces wrong direction.
oil filler tube: nope, no leak.
cracked block: unsure and highly doubt it.

Here's the symptoms, some how the oil is coming up by the fly wheel and getting blown around and out the driving side of the engine. it seems to push out a good amount of oil, enough to have me add more before I start it. It has recently started to smoke out the exhaust, which it never has before and it does it enough to make it hard to see inside the shed very quickly.

I have some pictures but I can't figure out where the oil is coming from, any one know where it might be coming from? and seals that I may have missed?

:thanku::thanku:

 

[DTLMG]

Bill...

Sounds like time to do some cool CSI investigatin! Go to your local autoparts store and get a bottle of ENGINE OIL dye. put a small amount into the engine oil...ASK your auto part store or a mechanic friend for his UV light to look at the oil..you will be able to pinpoint it this way!

 

[gray wolf]

sometimes it,ll blow oil past the head bolts and head gasket.if shes smoking that bad rings and maybe a valve job.

 

[BillTheTractorMan]

sometimes it,ll blow oil past the head bolts and head gasket.if shes smoking that bad rings and maybe a valve job.

the leak is coming from some where lower I think, I don't know when exactly but it went from with in an hour of use to no smoke, shut down to starting the next day and instantly filling the shed with smoke. I'm guess I'll end up with putting at least rings in it but unless I can get them on rather not expansive side this engine/tractor might find a home in the woods until I manage to get my hands on some. I will see about checking things out, I know it has 90psi of compression still, same as when I bought it 4-5 months ago..

 

[tomw0]

Have you checked the crankcase ventilation? Could be building internal pressure, pushing the oil out the least secure route. I don't know of rings that go that quickly, unless severely overheated causing scoring. Is there a pushrod that operates the points, as in the oil is being pushed out the pushrod hole?
tom

 

[BillTheTractorMan]

Have you checked the crankcase ventilation? Could be building internal pressure, pushing the oil out the least secure route. I don't know of rings that go that quickly, unless severely overheated causing scoring. Is there a pushrod that operates the points, as in the oil is being pushed out the pushrod hole?
tom

no points on this engine, it's SSI. I will see about getting some degreaser and cleaning it up than I will try to open the valve cover and check inside there.

now onto another thought that has morphed of an earlier response, could a blocked breather make oil blow through into the intakes/exhaust valves guides and cause this? even to the point of leaking out the head? I will try and get my compression tester and test compression.


Another thing to mention is lately it has also lacked power a little, I would put it in 3rd high, red it up and it would die if I didn't have it 1/4 choked. I passed this off as needing a carb cleaning but with the current issue I'm not going to throw anything out. It also would push out a little plume of smoke when I reved it up really fast or let out the clutch too fast, I figured this was unburnt fuel but I'll mention it here.

money is tight, so I'm looking at the paper towel and degreaser method since I will end up buying that stuff any way.


:thanku:


Edit: the shrouds were very clean(except oil) and I would get so much air blowing through them it felt like a cool fan blowing on me if I was standing on that side of the engine.

 

[Onan18]

Tom, looking at the picture I think that engine has solid state ignition, but I like the idea of it being excessive crankcase pressure, possibly it is one of the earlier SSI engines that still had the hole in the block for a points plunger that was just plugged and the plug has gone AWOL?

 

[BillTheTractorMan]

Tom, looking at the picture I think that engine has solid state ignition, but I like the idea of it being excessive crankcase pressure, possibly it is one of the earlier SSI engines that still had the hole in the block for a points plunger that was just plugged and the plug has gone AWOL?

this is an older tecumseh, I can tell it's not original to the tractor and I was told it was off an older tractor. Now where would I find the hole where the plug should be?

 

[Onan18]

I am not sure, not really a Tecumseh expert. I have only ever had one tractor with a Tecumseh and it had a Failed SSI unit. Sold it as a parts tractor and doubled what I had in it! I am sure a more knowledgeable person than me will chime in, though.

 

[Tractor-Holic]

The points (if it had any) would be located on the side of the engine where the pulleys are,on the lower right hand corner of the side cover--there will be a plate with two screws holding it tothe side cover,in there is where the points would have been,and the plugged off push rod hole...I wish ALL HH engines had that points passage drilled for a push rod,it would make a lot of owners on them with dead SSI ignitions happy~..at least then you could put points on it and use a car coil!..but most had no passage drilled and even had a different cam that lacks the lobe to operate the pushrod..

Your oil leak could be a breather problem,that lets pressure build up in the case and it might be forced past the crankshaft seal on the flywheel side..

 

[BillTheTractorMan]

When I get my tires and rims back I will pull it out and look at it some more. The leak, any oil is all above the plate behind the flywheel, none of it goes below that point. The wettest and cleanest oil is where the cylinder and the crank case meet, where the cooling fins stop I guess is the best way to put it. I will try to clean to all off and see the best I can, I will also take the valve cover off and clean out the breather to see if it helps any.


I don't plan on putting this back together to run it just to see where a leak is, it's too much work getting all the stuff out of the way I think. Stupid over engineered stuff that lasts for ever.... and is a pain to take apart to access stuff to repair it... LOL


:thanku::thanku:

 

[WNYTractorTinkerer]

Best way I can figure is to plug up the intake & exhaust and Breather and introduce a little air pressure into the CC via a compression tester hose (with the valve removed).. Spray the area with soapy water and look for bubbles.. :goodl:

 

[BillTheTractorMan]

New list of symptoms:

Oil on both top and bottom of head gasket
oil EVERY where except in the cylinder and flywheel
Head bolts are coated with a very nice thick coating of oil


My conclusion, or thought is I broke the oil keeper ring causing oil to get into the combustion chamber and being forced out through the head gasket from the 170psi compression.


Any ideas before I start pulling'er apart tomorrow. I checked the breather and it's not clogged.


If this ends up needing new rings, does any one know any one with a ring set for this engine?


I did however get a set of free used tires from a co-worker so threes a lot of lighter fluid on the fire to get this back in A+ running order.


:thanku::thanku:

 

[BillTheTractorMan]

Here's some pictures, if they help any. I just can't think of why it would go from not loosing any oil to having a blown head gasket, oil every where and burning oil between putting it away for the night and driving it out to pull the other tractor out to mow. I found some head gaskets, I plan on ordering them today so I can hopefully get them by Friday.


Any ideas on where to look? I don't want to pull this apart yet, or at all if possible. I'm going to pull the valve cover now, even though it probably will come up with nothing for the cause.

:thanku::thanku:

 

[tomw0]

The likelihood of the oil control ring sticking and the other rings not is low. If you have good compression, I would not be looking at putting in new rings. Looking at the picture of the top of the block and the cylinder bore, I'd say you were running rich. You have a pretty good carbon deposit on the top of the block.
If the carb is sort of broken, could it have added some extra fuel to the crankcase, and raised the oil level enough to cause frothing and such, leading to your symptoms? Fix the carb, it's too rich. Put the head back on after removing the carbon deposit. Use a torque wrench to make sure the head is tightened evenly. Give it a whirl. You might also check the valve clearance as your valve tulips don't appear 'normal'. The exhaust should be dry and it looks pretty carbon-ed up at a low temp. Heck, check both clearances and lap the valves in. I bet it would do fine without any new parts. Oh, I have been wrong before, too.
tom

 

[BillTheTractorMan]

What should I look for when it's running "rich"?, I can't smell anything so that sense is of no help. Which screw might I need to adjust? high speed or idle? They are at factory settings right now. I have noticed in the last couple hours maybe 2 at most when ever I go to pull off in 3rd-hi it will die unless I choke it at half throttle. could that be cause by the head gasket blowing? I'm at total confusion with this engine right now, the oil does did not have any fuel in it and never seemed to have bubbles in it after running it for a little bit.



:thanku::thanku:

 

[LilysDad]

I know it has 90psi of compression still, same as when I bought it 4-5 months ago..

"I will try and get my compression tester and test compression."


"My conclusion, or thought is I broke the oil keeper ring causing oil to get into the combustion chamber and being forced out through the head gasket from the 170psi compression."

Sorry, but you seem to be really confused about your diagnoses. You need to get a method to your search. You've had some good advice here. Follow it.

 

[BillTheTractorMan]

"I will try and get my compression tester and test compression."


"My conclusion, or thought is I broke the oil keeper ring causing oil to get into the combustion chamber and being forced out through the head gasket from the 170psi compression."

Sorry, but you seem to be really confused about your diagnoses. You need to get a method to your search. You've had some good advice here. Follow it.

I'm not sure on my diagnoses, I know that I'm going to put a new head gasket on it and run it some more to see if it happens again. I cleaned the engine and I found no cracks, bad gaskets (except head gasket) or oil seals leaking. Some how the oil is making it into the combustion chamber and was escaping out under the head gasket. I did clean as much of the carbon build up as possible with a wire brush and screw driver. The air compressor is currently unplugged because we are out of fuses and lately places seem to not have the fuses we need, I'm trying to hunt this down with what I have and with in what I can afford with my last $20.


The worst part of this is after moving out I have only been able to have one trip to get stuff and I have at least a truck load of stuff still over there. most of that is tools and computer stuff, so my compression tester and other tools are over there.


:thanku::thanku: