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As mentioned in a couple of posts I have been working on what was originally a parts tractor I got when I bought a 30" M106 mower and a rotary plow off e-bay. After I took the head off (was almost off anyway and they broke the cylinder and the head) and realized that the engine had very little time on it I decided to break it down further and maybe rebuild it into a kind of Frankenstein LI using a 7.6 head (milled 0.065") and cylinder (0.020 over bored), relubed governor and other modifications. Inside of the main case was surprisingly clean and free of any dirt or sludge. According to the seller the tractor was stored in a shed or garage and no water ever got into the engine/transmission. Took the front casting off to re-gasket and the clutches are like new and very tight. Resealed the axle castings with new double seals and sealant on the gasketed surfaces. Painted with two coats of low sheen black (original color as far as I can tell) spray paint from TSC. Have all the parts for the engine which is next. Now need to decide which red paint is correct for the bolt on parts around the engine and the hood and whether the hubs and rear start pulley are grey or off white in color.
Attached a few photos to show the before and after, at least on the transmission case.
 

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That looks great! More pix please!
 

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Your black does look nice but it is not original though it might tend to radiate heat pretty well which is a plus. Henry Ford is supposed to have said you can have any color you want on your Model T as long as its black so ignore me please I insist. A gravely source in Colorado named Steve Chalmers has lots of information on rebuilding if you need it. Maybe more to the point he has original literature files with color photos that show pretty well what these tractors looked like. Those heads on the floor in the first photo what did they come off of?
 

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Discussion Starter #4
Thanks
I realize that the black I used may not be completely correct but the tractor was definitely all original and the transmission castings were all originally painted black with no other paint underneath. Will check Steve's site again and look at the color photos.

The heads next to the compressor are off a 2002 Dodge R/T Dakota Magnum 360 with 250,000 miles. That's the crank between them. The three pieces all seem to be usable with just a polishing on the crank and maybe a crack check on the heads. One piston popped its upper ring land off and I changed the engine long block out for a 100,000 mile take out engine. Drove it another 35,000 miles until the body just plain rusted to death.
Used just the block to build a 408 stroker engine w/ Australian made Magnum heads and a Thermoquad carb which went into a 1987 Dodge Ram 150 I got from Oregon; all original with absolutely no rust.
 

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Discussion Starter #5
I scrolled through a number of Steve Chalmers' PDFs and photos and if anything it looks like Gravely changed paint colors all the time. Some were painted a solid red or solid orange/red while others were black cases with red painted bolted on parts. I think I still will like the black w/ red combination I am planning. Still need to pin down a suitable match to the 1961 red and what color the wheel hubs and starter pulley really are; grey or off white. Right now they look to be grey.

Finding that with Gravely stuff you will find most anything could have come out of the factory.
 

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Discussion Starter #6
Pictures I took this morning:

Underside of 7.6 head after I had it milled 0.065". There is still 0.070" or so left on the shallow side which I think could be milled off too for a total of 0.130-135" or so. Would not want to take this much off the 5-6.6 heads as they are much thinner and lighter in cross section. With the depth of the valve pockets plus the gasket (@ 0.040" on the two new ones I have) there is no way the valves can hit seeing as the actual valve lift is around 0.25+". On a flat head motor as you mill the head you begin to reach a point of diminishing returns because the valves become more shrouded and flow rate drops. I am just looking for a little more compression seeing that the original compression ratio is in the area of 5:1 or a little more (at least from what I have been able to find). As a general rule, adding compression is the quickest way to add power (within reason). Plus efficiency goes up too.

The shot of the aluminum crank case shows the single oil drain-back hole I drilled @ the very bottom. This tractor definitely was built with a high volume oil system but it did not have the oil drain holes in the bottom of the case and it has a oil drain plug on the back under the oil pump. The connecting rod is the new style I beam type but does not have the two holes on the upper side of the big end pointing at the piston/cams. Bottom of the big end is drilled and chamfered. As a little added insurance I drilled a single 0.040" hole in the front case @ the main oil feed to the main/rod bearings (the raised bump-out in the casting) pointing up towards the piston. Hopefully this will help lube both the piston and throw off from the crank will keep the cams lubricated too. While the valve spring pressure on these engines is very low compared to automotive engines, they still have sliding friction between the cam and followers so I strongly suggest that oil with the correct additives be used (will be using a cam break-in oil for the first fill). Also, I hope that the single drain-back hole will slightly impede flow back to the transmission case during operation and additional crank throw off will occur.

Just my opinion on how to slightly upgrade the T head.
 

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Discussion Starter #7
These two shots show how I expect to use studs to hold the head to the cylinder casting. On the left (exhaust side), I am showing the shorter studs (all studs are coarse thread into the cast iron and fine thread nuts) with the ANSI washer and nut and for the shroud stud, using a double nut and washer to fasten the shroud. On the right (intake side) I located some fine thread coupling nuts and would torque down the head and then add a short bolt to hold the shroud. The third method I came up with would be to use a long stud with a bottom nut torqued down and then a spacer (steel or aluminum) with a second nut to hold the shroud. Leaning to either #1 or #3. As I see it, the studs allow a more uniform clamping load on the head/gasket and should be easier to remove in the future. If a rust/corrosion problem develops you can always grind the top of the stud off with a die grinder to get rid of the rust in the threads and then the nut should just come right off. Studs are hardened and the nuts are grade 8 cad plated and will all get a liberal coat of hi-temp anti-seize paste.

Intake port already had coarse thread studs installed and from the looks of the port and the area around it this cylinder had been installed backwards and the port was actually used as the exhaust (and the valve was marked with "EX"). One of studs refused to come out so I plan on using them as is with self locking nuts. The now exhaust port (which does have a bronze guide) will have a set of coarse/fine studs installed and a double nut setup used to protect the threads from rust so removal of the exhaust manifold will be easier in the future. Again all threaded connections will get anti-seize.

And note; this cylinder is not going on the LI engine but rather I expect to install it on the 1969 L/C-8 hooked to the Sno-cannon due to a bad lack of power and a lot of blow by. The cylinder and piston are 0.020" OS and was almost unused so I just had the machine shop hone it for new chrome rings and hand lapped the valves w/ a new upper valve plate gasket. Should solve the power problem and be are relatively easy fix. Also, this setup is a trial for the LI engine on what works best.
 

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You will have issue closing the Hood with the 7.6 head, that is if you want to used the original hood. Gravely redesigned the hood when the 7.6 came out as straight plug gut in the way. Funny some hate the later good, I rather like it as it covers the fuel tank.

Without knowing the serial number its a guess as to the year. Knowing the year will determine the paint colors. I’d say it’s a transition year close to when Gravely introduced the high volume oil pump. You can also see where the transmission would have had a center drain. The plug under the oil pump is to drain the oil from the crankcase which was a hold over from the low volume oil pumping wet sump. As you’ve seen the early high volume pumps did not have crankcase to oil sump drains so it was still necessary to drain the crankcase. Later L’s had two oil drain holes and no crankcase oil drain plugs.


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Discussion Starter #9
Tractor serial number indicates that it is a 1961 (M62758), and as far as I can determine, it never was taken apart or modified at all. Back half of main engine case has two raised pads where the original oil pump connections would be so I'm guessing the factory was just using up left over cases. Maybe why there was a drain plug in the back and no holes in the front. The "wet" vs. "dry" sump is not a big deal except for starting when cold; a sump full of cold oil to the level of the vent holes would be a big drag on a hand start. Plan to use 10W-30 in this engine and have used Rotella 10W-30 in the other two tractors to date.

Had the local auto parts paint department use their scanner on the best paint patch I could locate on the tank under the fan shroud. Didn't match to anything in their system, just called it "cherry red". Single quart of acrylic enamel was about $100!!! Looks like dark tractor red to me. Red and yellow paint colors are very pricey.
 

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Try "gravely paint" in the google custom search box. It gave me whole bunch of suggestions just on first page. Nice truck hope you pin striped it in gold.
 

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And as far as the statement about the 7.6 head spark plug location hitting the original flat hood, I never considered it! The other two tractors are convertibles w/ electric starts so they have the big hoods. It maybe a good time to look into reversing the head casting on the cylinder to move the plug back towards the tank and nearer the exhaust valve. Fivetractor guy (Jake from MA) sent me a link on modifying Kohler flathead heads for mini tractor pulling (Information About Cylinder Heads For Kohler Engines). It appears from the Kohler factory modifications over the years that moving the plug towards the exhaust helps with both power and efficiency. Don't see why it would not work for the T head. Don't think it will affect anything regardless. And maybe solve the hood fit issue (I like the flat hood look).

After reading the link on the Kohlers, I did remember that almost every B&S or Tecumseh engine that I looked down the plug hole had the plug favoring the exhaust side of the chamber and not the intake. And I think that that old Ford flathead V8s especially the aluminum after market heads are laid out the same way.
 

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Save your self a lot of time, money and effort, trying to make " performance" improvements to the Tee head engine. They won't make any noticeable improvement. To be honest I find no difference between a 5.5 HP and a 7.6HP engine, in tune. Paint it what ever color you like. Any paint job, or lack of will not effect the value of the tractor in any way.
 

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Save your self a lot of time, money and effort, trying to make " performance" improvements to the Tee head engine. They won't make any noticeable improvement. To be honest I find no difference between a 5.5 HP and a 7.6HP engine, in tune. Paint it what ever color you like. Any paint job, or lack of will not effect the value of the tractor in any way.


Couldn’t agree more with the above statement


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And as far as the statement about the 7.6 head spark plug location hitting the original flat hood, I never considered it! The other two tractors are convertibles w/ electric starts so they have the big hoods. It maybe a good time to look into reversing the head casting on the cylinder to move the plug back towards the tank and nearer the exhaust valve. Fivetractor guy (Jake from MA) sent me a link on modifying Kohler flathead heads for mini tractor pulling (Information About Cylinder Heads For Kohler Engines). It appears from the Kohler factory modifications over the years that moving the plug towards the exhaust helps with both power and efficiency. Don't see why it would not work for the T head. Don't think it will affect anything regardless. And maybe solve the hood fit issue (I like the flat hood look).



After reading the link on the Kohlers, I did remember that almost every B&S or Tecumseh engine that I looked down the plug hole had the plug favoring the exhaust side of the chamber and not the intake. And I think that that old Ford flathead V8s especially the aluminum after market heads are laid out the same way.


Moving the plug away from it’s location could decrease power, you want the spark to occur close to where the intake charge is.


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Discussion Starter #17
Update:

Finally got the engine reassembled and mounted to the transmission. Decided to use the milled 7.6 head turned around so the plug is back to the fan shroud and nearer the exhaust. I still don't think it will have any affect on the power and it will also (maybe) keep the plug colder. May have to use a shorter plug (J17LM) so the original slant hood will fit but not there yet.
Also used one two piece valve box and one CI one piece valve box due to issues with one of the CI units. Don't see any problems with this as all the gaskets are new and sealed up real good.
And lastly, mounted the head using studs set into the jug, loc-tited and pre-stretched before torquing the head down. Head gasket is the composite type, not copper like I wanted to try.
 

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If I cant use my orig. hood Im gonna be one sad dude. I stripped it to the shiney bare metal and painted a few coats of white on it, bought new bumpers, put a coat of Turtle wax on it and have some decals to put on it.
My 1966 L is gonna have the white hood and the rest of it is I.H. Red.
And the new white wheels/rims w/the duals on it it should look nice. May never run ever again but its gonna look nice lol!
 

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If I cant use my orig. hood Im gonna be one sad dude. I stripped it to the shiney bare metal and painted a few coats of white on it, bought new bumpers, put a coat of Turtle wax on it and have some decals to put on it.
My 1966 L is gonna have the white hood and the rest of it is I.H. Red.
And the new white wheels/rims w/the duals on it it should look nice. May never run ever again but its gonna look nice lol!
Gerrard,
I laughed when I read that about the hood as your timing is spot on with a recent experience of mine! Saturday morning I pulled the fan assembly off of my 74 C8 to inspect and lube the fan bearings as I was installing a new fan belt. Once I had it back together I said to myself "why don't I FINALLY put the hood on this machine?". When I repainted my first pair of Gravleys three years earlier, I, like you, prepped, prepared, and painted my hood but never operated the machine with the hood as I think I remember that it 'rattled' too much. Fast forward to a later time when I disassembled that same machine to align the crankshaft and that vibration was gone... still, I never reinstalled the hood.

Well, I did install the install on Saturday and it looks nice! I cranked the machine and the earlier rattle noise was not there. This will undoubtedly save me some headache as I cannot tell you exactly how many times that the spark plug wire has been pulled off of the spark plug while I was brush-cutting and this should eliminate 99% of those events PLUS the machine looks pretty cool with the hood in place.
 

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Well, I did install the install on Saturday and it looks nice! I cranked the machine and the earlier rattle noise was not there. This will undoubtedly save me some headache as I cannot tell you exactly how many times that the spark plug wire has been pulled off of the spark plug while I was brush-cutting and this should eliminate 99% of those events PLUS the machine looks pretty cool with the hood in place.
Thats great Fireant, heck just with my push mower everytime I get around bushes and the like my gas cap gets twisted off/loose and have had to find it many times but I can see where it will save plug wire and a lot more debris that could get all up under there.
Cosmetics on mine is important because its my goal to give him (son) a nice new looking and hopefully running Gravely and I can tell how well he is taking care of it that way too and spot leaks and stuff.
Im going to work here in a few, I work from noon till 8:00 or so wich is another reason to split-up my time on various projects,
Good hearing from ya
Take Care
Mark
 
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