Allis C main bearing cap shims and I & T Shop Manual

[atlarge54]

The manual calls for 4 shims per side. Does that mean each cap would have a total of eight shims? What is the thickness of the individual shims?

I've got a mystery rebuild job with a .010" under crank and .010" under bearings with 2 shims (.002") total .004" per side on bearing caps. The crank wants to bind slightly when torquing main caps.

The engine had very little use after a rebuild and exposed to water. Previous owner ruined a piston or two during teardown. I could not get ANY history on the tractor----just get it loaded and get it out of here. It was REALLY cheap.

 

[Jim.ME]

Has the crank been fully mic'd and checked for straightness?

 

[atlarge54]

No, I'm curious how the pistons were removed possibly a BFH and tweaking the crank. It seems the front main cap is more of a problem than the other two.

I actually ground a crank in place on my mowing C over 15 years ago. I'd bet it's so far under spec you couldn't purchase bearings for it. I didn't use any measuring devices just spun the crank with an electric motor and stoned the journals until they were smooth. I used all the old worn bearings and shimmed them between the block. Fitted all the caps using shims until they didn't bind up and slow down the electric motor. Bottom end of the engine is just fine to this day. I fitted the old rod bearing by hand the same way.

These are 125 cid and 20 HP low rpm, not Formula 1 engines.

Allis C's are NOT a high value commodity around here. The value of the rims/tires is the big determination of the tractor's value.

 

[DrAllis]

I thought a "shim stack" was .010". Each shim stack was FOUR .0025" shims glued together as one. You peeled them away one at a time to get shim thickness to where you wanted them. One "shim stack" per main bearing bolt/side.

 

[mrhud]

have journals been measured with a micrometer , are the rods conected when it gets hard to turn. are the main seals correct

 

[atlarge54]

have journals been measured with a micrometer , are the rods conected when it gets hard to turn. are the main seals correct

Block is bare no rods, I'm just using dial calipers so far I didn't drag out the mic's. The rods fit the journals nicely. I'm questioning the last rebuild somewhat, they didn't replace the cam bearings and on this particular engine the cam bearings are EXTREMELY critical to the oiling system.

 

[d13series1]

The stock pack is designed to have shims removed as the bearings wear. If the crank is binding it needs shims added. Check that the bearings will still have enough crush to prevent spinning. Best bet is to mic the crank and check for flatness across the journal. Is the problem only on one bearing or on any of them?

 

[atlarge54]

The stock pack is designed to have shims removed as the bearings wear. If the crank is binding it needs shims added. Check that the bearings will still have enough crush to prevent spinning. Best bet is to mic the crank and check for flatness across the journal. Is the problem only on one bearing or on any of them?

Front cap is the worst, a thou or two on the other caps might not hurt. I'm not even sure about dumping a bunch of money into this engine. Just an old retired fart messing around.

 

[Dick L]

The manual calls for 4 shims per side. Does that mean each cap would have a total of eight shims? What is the thickness of the individual shims?

I've got a mystery rebuild job with a .010" under crank and .010" under bearings with 2 shims (.002") total .004" per side on bearing caps. The crank wants to bind slightly when torquing main caps.

The engine had very little use after a rebuild and exposed to water. Previous owner ruined a piston or two during teardown. I could not get ANY history on the tractor----just get it loaded and get it out of here. It was REALLY cheap.

I have ran into this many times using inspec non reground Allis B and C crankshafts.
If the crush is more than called for the bearing shells push inward and can even stop the crankshaft from turning when tightened to specs. Here is a link to filing bearings.
https://public.fotki.com/DickL/allis_chalmers_engi/filing-main-and-rod/

Filing Main and rod Bearings

DickL photos: Filing Main and rod Bearings -

public.fotki.com

 

[atlarge54]

I have ran into this many times using inspec non reground Allis B and C crankshafts.
If the crush is more than called for the bearing shells push inward and can even stop the crankshaft from turning when tightened to specs. Here is a link to filing bearings.
https://public.fotki.com/DickL/allis_chalmers_engi/filing-main-and-rod/

Filing Main and rod Bearings

DickL photos: Filing Main and rod Bearings -

public.fotki.com

I think you're on the right track---I put some Dykem on the worst offender and it shows a bit of contact in the crush zone.

These old C's are the Rodney Dangerfield of tractors----No respect.

I didn't get the one in Cecil Ohio and don't regret it. I've got a line on a couple more right now just to get some tires. If I was younger and had a bit more storage it would be scary how many I might own.

 

[Dick L]

I think you're on the right track---I put some Dykem on the worst offender and it shows a bit of contact in the crush zone.

These old C's are the Rodney Dangerfield of tractors----No respect.

I didn't get the one in Cecil Ohio and don't regret it. I've got a line on a couple more right now just to get some tires. If I was younger and had a bit more storage it would be scary how many I might own.

I ended up with over 40 tractors and still have about 40 in one condition or the other. Never thought about tinkering on them would come to an end so soon. Almost to an end!
I regret not copying and pasting what I posted with the picture on fotki. This was a after work hobby and was a little selfish in trying to get a few hours of sleep most days.
If you get deep into this here is a C engine with a D 15 crank rebuilt to a 4 inch stroke. This C engine was balanced. this picture shows where I ground away the webs so the crankshaft would rotate. SMB block valves and ,200 milled off the head. Also a Crane ground camshaft shaft.

Photo: clearance for crank | Installing SBC Valves In C - B - CA album | DickL

DickL photos: clearance for crank

public.fotki.com

 

[atlarge54]

I ended up with over 40 tractors and still have about 40 in one condition or the other. Never thought about tinkering on them would come to an end so soon. Almost to an end!
I regret not copying and pasting what I posted with the picture on fotki. This was a after work hobby and was a little selfish in trying to get a few hours of sleep most days.
If you get deep into this here is a C engine with a D 15 crank rebuilt to a 4 inch stroke. This C engine was balanced. this picture shows where I ground away the webs so the crankshaft would rotate. SMB block valves and ,200 milled off the head. Also a Crane ground camshaft shaft.

Photo: clearance for crank | Installing SBC Valves In C - B - CA album | DickL

DickL photos: clearance for crank

public.fotki.com

You probably don't have a video of it running? That's quite an interesting project.

You're a good man Charlie L.

 

[Dick L]

You probably don't have a video of it running? That's quite an interesting project.

You're a good man Charlie L.

I do have one video at a tractor pull. In the video the first pull I was in second place about a foot from first. I had idled down thinking I could get more traction. I miss read the track. On my second pull I added RPM to keep the sled from slowing any and the flagman told me please don't go out in the mud.