1952 compression

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Bill V in Md
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Re: 1952 compression

Postby Bill V in Md » Tue May 04, 2021 4:19 pm

dterhaar2000 wrote:I will check the ring gap. What should the gap be on the rings?


The gap on the compression and oil control rings should be 0.007 - 0.017 inch for the original pistons.
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Re: 1952 compression

Postby SamsFarm » Tue May 04, 2021 5:27 pm

A good method people like to use when checking ring gap, is once you place your bare ring in the cylinder, then put a piston into the bore and use the top of the piston to make sure your ring is perpendicular to the bore, then remove the piston and check your ring gap being careful not to disturb the ring!

dterhaar2000
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Re: 1952 compression

Postby dterhaar2000 » Tue May 04, 2021 6:57 pm

Would the .007 to .017 inch still be same for new aluminum pistons?

Stevetractor
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Re: 1952 compression

Postby Stevetractor » Tue May 04, 2021 7:29 pm

Your compression was real low before you started. Putting rings in a worn out bore won’t fix it. These engines turn slow and with 70 years of wear, need a proper rebuild. Bore block, turn crank, new valves, springs, guides, plane head and manifold. I’m not trying to be negative at all either. But I have learned that by doing a proper and complete motor job these little engines really come alive. I also usually rebuild, distributor, governor, check oil pump, and check oil pressure plunger and spring while I’m at it. By following everyone’s help, hopefully you can get yours going, but it’s really hard cutting corners on motor work. I’m also lucky I have a great machine shop in my area and can do the tear down and assembling myself.

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Bill V in Md
10+ Years
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Posts: 980
Joined: Sun Feb 02, 2003 6:51 pm
Zip Code: 21228
Tractors Owned: 1948 Farmall Cub
LT1045 Cub Cadet
Circle of Safety: Y
Location: MD, Catonsville

Re: 1952 compression

Postby Bill V in Md » Tue May 04, 2021 7:52 pm

dterhaar2000 wrote:Would the .007 to .017 inch still be same for new aluminum pistons?


Wait, what? Do you have new aluminum pistons, or are you considering them? I thought you were just trying to take some short cuts and get a tractor with low compression running for the short term. However, if you have the time and money, I think Stevetractor's recommendations make a lot of sense.
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ntrenn
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Re: 1952 compression

Postby ntrenn » Tue May 04, 2021 10:11 pm

It’s kinda important to know how much ring end gap you started with. My 65 came to me with upwards of 0.125 end gap. That alone is enough to have a significant effect on compression readings.
That much ring gap came about by ring wear, not bore wear in my case. A new set of rings and a tiny bit of filing and they came right back to spec.
Always touch up the valves and lap the seats if you have the head off. Valves are a couple of bucks each to touch up and lapping compound and a manual lapped is cheap..$20 all in.

dterhaar2000
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Re: 1952 compression

Postby dterhaar2000 » Wed May 05, 2021 7:54 pm

I bought the piston and ring kit. I measured my cylinders and the was the standard size 2.625 inch. I also bought valve kit with valves, springs, valve guides, and keepers. I also lapped the valve seats.
I took the pistons back out and my ring gap is .032 inch. So I'm going to look into ordering different set of rings. Would .020 overbore and file them down work?


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