Bad compression

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ParlowMillFarm
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Zip Code: 02738
Tractors Owned: 1949 Cub
1964 JD1010
Location: Marion, Massachusetts

Re: Bad compression

Postby ParlowMillFarm » Mon Oct 17, 2016 9:15 pm

Glen,
Thanks for the reminder, I forgot about that.

John

ParlowMillFarm
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Zip Code: 02738
Tractors Owned: 1949 Cub
1964 JD1010
Location: Marion, Massachusetts

Re: Bad compression

Postby ParlowMillFarm » Thu Oct 20, 2016 10:10 am

I put some oil on the #1 piston overnight and it was gone in the morning :(

Also noticed some scoring (albeit very light) in the #4 cyl. :( :(

Took engine apart (except for the issue below) and noted flaws on all the piston bearings - and issues with the crank.

Yes Eugene, total rebuild needed. Also thanks to your advice, as I could have just tried a quick fix without breaking this engine down and seeing some issues that would otherwise be hidden from view. It's better to have it apart in the barn than broken down in the driveway in the middle of a snowstorm.

And since I read the posts here, before I took the governor off I set the engine to TDC (easy with the head off) and took a photo of the gov.

Govenor position1.JPG
this photos makes it easy to remember correct position!


Question: Any trick to getting the front wheel off the crankshaft?

Eugene
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Re: Bad compression

Postby Eugene » Thu Oct 20, 2016 10:45 am

Search function for "crankshaft pulley puller". There will be several photos of the design and how it's utilized.

You need a special puller or a heavy duty bearing splitter to remove the pulley.

If a machine shop is going to rebuild the engine, let them remove the pulley.
I have an excuse. CRS.

ParlowMillFarm
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Joined: Mon Oct 17, 2011 4:56 pm
Zip Code: 02738
Tractors Owned: 1949 Cub
1964 JD1010
Location: Marion, Massachusetts

Re: Bad compression

Postby ParlowMillFarm » Thu Oct 20, 2016 3:31 pm

Crank is at shop.

Have to measure borings on block to make sure it's salvageable.

ParlowMillFarm
5+ Years
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Posts: 157
Joined: Mon Oct 17, 2011 4:56 pm
Zip Code: 02738
Tractors Owned: 1949 Cub
1964 JD1010
Location: Marion, Massachusetts

Re: Bad compression

Postby ParlowMillFarm » Thu Oct 20, 2016 5:11 pm

Checked the bore with imprecise measuring device, but 2 5/8 hit the mark, so I'm ok on that.

:arrow: But.... noticed hairline crack that extended about 1/2 to 3/4 in into the block. [You can easily see it if you click on and magnify the picture]

Block crack 2.JPG
Note crack at left end


Is this salvageable? or toast ?

tst
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Re: Bad compression

Postby tst » Thu Oct 20, 2016 6:03 pm

that is where the early blocks crack,can be welded, check it close as the crack may be longer than you think

ParlowMillFarm
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1964 JD1010
Location: Marion, Massachusetts

Re: Bad compression

Postby ParlowMillFarm » Sat Oct 22, 2016 9:12 am

Thanks tst for the input.

Does anyone have any thoughts or reviews on the new crankshafts available on the internet?

They are about the same price as a regrind and the regrind is done to a better than needed tolerances (which is good).

ParlowMillFarm
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Tractors Owned: 1949 Cub
1964 JD1010
Location: Marion, Massachusetts

Re: Bad compression

Postby ParlowMillFarm » Mon Oct 24, 2016 3:57 pm

I have a set of valves I will not be reinstalling. Free to a good home.

ParlowMillFarm
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1964 JD1010
Location: Marion, Massachusetts

Re: Bad compression

Postby ParlowMillFarm » Thu Dec 01, 2016 5:23 pm

Went to the Machine shop today. Block and head have been baked and cleaned.

It was determined that the cylinders were honed to 2.634" during the 1980 rebuild. Problem is the original pistons were put back in. The small irregularities in the honing will require boring out to .020" from the original.

Crankcase gets reground next week. Rear main seal gets sent to Tim tomorrow.

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Re: Bad compression

Postby CapeCodCubs » Thu Dec 01, 2016 10:48 pm

Making some progress, John. Where did you wind up getting the engine work done?

Chris
Image

ParlowMillFarm
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1964 JD1010
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Re: Bad compression

Postby ParlowMillFarm » Fri Dec 02, 2016 10:48 am

Chris,

Advanced Engine Rebuilding Inc. in Wareham Center, 176 Main St, Wareham, MA 02571, Phone:(508) 295-2288. Not too far for you.
Google has some interesting photos of some of their work from 2013.

John

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Re: Bad compression

Postby bofahs » Sun Dec 04, 2016 1:09 pm

10 is not "bad compression" - it's NO compression - I think you're just measuring the force of the air blown up by the piston into the guage. Now, others may vary, but I've seen this caused by sticky valve guides - that is - a valve gets stuck open and has to be (hopefully) pried back into position. Back in the 90's, when I had first gotten my '65 Lo Boy, this happened to me three times over the course of two years.

I'd pull the side cover, reach in with a monster screwdriver and, after spraying in some lube, crossing fingers that nothing would break, would pop the valve back into position. I received some GREAT advice and, ever since, always add a couple ounces of Marvel Mystery Oil to each tank of gas. (Of course I also use MMO in the crankcase) Here it is, 2016 - just mowed 5 acres, and I've never had the head off.

For what it's worth.

ParlowMillFarm
5+ Years
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Posts: 157
Joined: Mon Oct 17, 2011 4:56 pm
Zip Code: 02738
Tractors Owned: 1949 Cub
1964 JD1010
Location: Marion, Massachusetts

Re: Bad compression

Postby ParlowMillFarm » Fri Dec 16, 2016 2:19 pm

I'm getting back a retooled block with all the new parts I need next week. (Reassembly at the machine shop is backed up to next May, so I will be doing the reassembly.)

I have Blue Ribbon Service Manuals "Form GSS-1008 SPECIFICATIONS Farmall Cub and International Cub lo-Boy Tractors," and "Form GSS-1007
Engine, Fiie: Fannall Cub Tractor Service Manual."

Are those all the manuals I need?

And do I need a special tool to get the rings on? :help:

John

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Re: Bad compression

Postby Chipmaker » Fri Dec 16, 2016 2:32 pm

You don't need a special tool to get them on but you do to get the piston back in the bore, you will need a ring compressor available at auto parts stores. Probably less than $20. Be sure and put your rings on the correct way.
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tst
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Re: Bad compression

Postby tst » Fri Dec 16, 2016 2:50 pm

make sure to check ring and bearing clearance during reassembly


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