Compression check

Farmall H, HV & Super H, 300 & 350, 1939-1958
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Dusty B
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Joined: Wed May 23, 2007 7:35 am
Zip Code: 61736
Tractors Owned: '45 SC Case
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Location: IL, Downs

Compression check

Postby Dusty B » Sat Oct 17, 2015 7:35 pm

Did a compression check - first time dry - 90 on 3 cyl, 50 on one - added a couple of squirts of oil, 100 on 3, 60 on one! Is the 100 pretty average for an H?? Finally got carb back and ready to put on, gas tank cleaned, painted and remounted! May run yet before winter!! Dusty B
Grandpa's '41 B
'56,,'57,'59, Cu'b
'45 C
'55 Case S
Dad's DB garden tractor
'48 DeSoto
'31 "A Coup
'79 Lincoln TC
God looks out for those of us who don't know how to look out for ourselves!

Eugene
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Re: Compression check

Postby Eugene » Sun Oct 18, 2015 7:47 pm

The wet compression test are low. Thinking the numbers should have come up more than 10 psi.

Probably valve problem. Check the valve tappet clearance.

Compression is good enough for the tractor to start and run. I would operate the tractor - engine for a length of time, then do the compression tests again.

90 psi dry, 100 psi wet, If this had been on all cylinders, I would leave the engine along. The one cylinder with low compression is a concern.

Until the results of the next compression test come in, thinking engine is due for a valve job.
I have an excuse. CRS.

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Dusty B
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Posts: 1784
Joined: Wed May 23, 2007 7:35 am
Zip Code: 61736
Tractors Owned: '45 SC Case
Circle of Safety: Y
Location: IL, Downs

Re: Compression check

Postby Dusty B » Mon Oct 19, 2015 7:50 am

K - This = has been sitting for a long time so don't expect it to be totally up to specs. Dusty
Grandpa's '41 B
'56,,'57,'59, Cu'b
'45 C
'55 Case S
Dad's DB garden tractor
'48 DeSoto
'31 "A Coup
'79 Lincoln TC
God looks out for those of us who don't know how to look out for ourselves!

Matt Kirsch
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Re: Compression check

Postby Matt Kirsch » Thu Oct 22, 2015 12:32 pm

Things may loosen up with some run time and copious amounts of seafoam.

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schmibm
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Re: Compression check

Postby schmibm » Sat Oct 24, 2015 8:01 pm

That old H will run for many years that way. I would get it running for a while and check compression again after a while. The rings are likely stuck a bit and there could be rust on the seats of the valves caused be the position it was parked in. After running for a while, most of these would be eliminated. No need to spend more money than necessary.

Are you planning to pull with it needing the full power?
1949 Project Cub
1955 Cub Lo-Boy "Jack"
1957 Cub Lo-Boy "Mac"
1957 Cub with 5' Woods Belly Mower "James"
24 other Farmalls A thru SMTA.

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Dusty B
10+ Years
10+ Years
Posts: 1784
Joined: Wed May 23, 2007 7:35 am
Zip Code: 61736
Tractors Owned: '45 SC Case
Circle of Safety: Y
Location: IL, Downs

Re: Compression check

Postby Dusty B » Wed Oct 28, 2015 5:55 am

Thanks guys - that was kind of my feelings too. Waiting right now for a replacement wiring harness from Lostant. Other than some attention to low tires should be ready to go next spring!! Going to look like Johnny Cash's Cadillac tho - repainting it piece by piece as I clean things up and/or replace them. Did set up a small electrolysis tank to do some of the small parts. Hood & grill w/have to wait until next spring for the big tank!! Dusty B
Grandpa's '41 B
'56,,'57,'59, Cu'b
'45 C
'55 Case S
Dad's DB garden tractor
'48 DeSoto
'31 "A Coup
'79 Lincoln TC
God looks out for those of us who don't know how to look out for ourselves!

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schmibm
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Joined: Tue Jun 06, 2006 10:37 pm
Location: Janesville, IA

Re: Compression check

Postby schmibm » Wed Oct 28, 2015 12:16 pm

Had a buddy that started that way on his F-20. He was on his first part the air cleaner. Had it all sanded down and painted real nice. Took it to a show and a guy walk by his tractor and makes the comment, nice air cleaner buddy. My friend felt very small. He went home pulled off the freshly painted air cleaner and replaced it with another rusty one. He hasn't worked on any more pieces since.
1949 Project Cub
1955 Cub Lo-Boy "Jack"
1957 Cub Lo-Boy "Mac"
1957 Cub with 5' Woods Belly Mower "James"
24 other Farmalls A thru SMTA.


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