Bad compression

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

Re: Bad compression

Postby ParlowMillFarm » Thu Jan 26, 2017 6:10 pm

So a progress report.
Recap- The fuel wasn't getting to the carb, the (rubber) fuel line leaked, the fuel bowl strainer was missing, the fuel bowl cork gasket had disintegrated (and was clogging up the carb), the fuel shut of valve was pitted at the end. The gas leaked all over the fresh paint. The carb had an aftermarket lever and shaft assembly that prevented any adjustment by the idle set screw.

(All this was explained in a Governor adjustment thread, but it seems like a hijack to continue the story there.)

Carb has been rebuilt with new non-rubber needle valve, the correct lever and shaft assembly, new dust seals, screen and everything else cleaned out.

New fuel line from TM, new shut off with no leaks all installed.

Now I have stripped out the threads of the fuel line intake on the carb. :cry:

Advice appreciated and usually followed.

John

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Glen
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Location: Wa.

Re: Bad compression

Postby Glen » Thu Jan 26, 2017 7:12 pm

Hi,
Sounds like you are making progress with the repairs.
I think I have read on here that the guys install a thread repair coil in the carburetor inlet, when the threads are stripped out. I'm not sure if there is one of them you can send your carburetor to for the repair or not. Maybe someone will write. :)

staninlowerAL
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Tractors Owned: Cubs: (3)'49's, (1)'52, (1)'57 IH Cub LoBoy w/FH, (1)'72 154 Number Series Loboy, '76 Longstripe w/FH, Mowers: C-22, Bush Hog 412, Pennington 59, Woods RM42CF, Woods 42, assorted FCub plows, planters, discs, etc. OTHERS: '49 AC B & Ind. Sickle mower, '61 AC D12 Ser 2, '52 8N, '56 Ferguson 35 Deluxe, '53 MM BG (offset), (2) '49 Avery V's, '56 JD 420C, with Blade and fire plow, '85 JD 850 (Yanmar) w/72" belly mower, '76 Yanmar 1500, Sears Surburban's, MTD's, Jeeps & other misc. "treasures"
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Re: Bad compression

Postby staninlowerAL » Thu Jan 26, 2017 7:58 pm

Helicoil is probably the best if you have the tools to do it or get someone to do it. Alternate fix if you have any threads left in the carb inlet you can use a brass 5/16 compression union and rethread one side of it with a 1/2 x 20 die nut (which is the carb inlet threads) and seal it in place with a sealer. Connect your 5/16 metal fuel line to the other side of the union with the nut and ferrule provided and you're good to go.

ParlowMillFarm
5+ Years
5+ Years
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 Jan 26, 2017 8:55 pm

Hey Stan,
I'll try the quick fix tomorrow. I have a lot of misc. fittings around... Seems like one in the bin should work.

John

staninlowerAL
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Tractors Owned: Cubs: (3)'49's, (1)'52, (1)'57 IH Cub LoBoy w/FH, (1)'72 154 Number Series Loboy, '76 Longstripe w/FH, Mowers: C-22, Bush Hog 412, Pennington 59, Woods RM42CF, Woods 42, assorted FCub plows, planters, discs, etc. OTHERS: '49 AC B & Ind. Sickle mower, '61 AC D12 Ser 2, '52 8N, '56 Ferguson 35 Deluxe, '53 MM BG (offset), (2) '49 Avery V's, '56 JD 420C, with Blade and fire plow, '85 JD 850 (Yanmar) w/72" belly mower, '76 Yanmar 1500, Sears Surburban's, MTD's, Jeeps & other misc. "treasures"
Circle of Safety: Y
Location: AL (Southwest)

Re: Bad compression

Postby staninlowerAL » Thu Jan 26, 2017 9:37 pm

ParlowMillFarm wrote:Hey Stan, I'll try the quick fix tomorrow. I have a lot of misc. fittings around... Seems like one in the bin should work.
John
Just be sure to have the correct threads to screw into the carb or you'll probably make bad matters worse. I've found the 5/16 compression union is the correct size just the wrong threads. The brass is pretty easy to rethread with a 1/2 x 20 die nut if you clamp the union in a vise.

ParlowMillFarm
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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 Feb 03, 2017 10:31 pm

A update:
I had the inlet to the carb tapped out to fit a 1/4 pipe thread and then got an adaptor to 5/16 compression to fit the steel line.
Have gas.
Had a nice blue spark burn would not fire up. I switched the plug wires around to determine if I was 180 off and got a better response, not not really anything one would hope for. The improvement did tell me that timing was an issue, so I took off the magneto and cleaned the grease off the gears and discovered that I had not installed rotor correctly. Thought I had, but.....
Now put magneto back on. Dead battery. Tried hand crank but no dice.

Installed new battery. Primed oil pump. Started right up. Ran hydraulics up and down to get air out of the system. Feeling good.

Put on timing light. They really don't like to run on a 6 volt positive ground system do they? Got a battery to power timing light. Determined I am 22.5 degrees off TDC. Was able to get to 1.5 degrees by turning mag all the way to the block. No wonder this wouldn't fire by hand crank!

My guess is I am off a tooth or two when I installed the governor. I do have an extra gasket for that, so tomorrow I'll try a corrected installation. Guess I missed the dots on the idler gear the first time.

John

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

Re: Bad compression

Postby ParlowMillFarm » Wed Feb 08, 2017 5:50 pm

:help:
I took off the governor and reset it. Replaced the seal because it had too much oil on the wrong side to be considered effective at doing its job. Also changed the oil.

Reset the magneto and started up the tractor - a horrible clanking sound from the front (I thought perhaps the fan was catching on something) and before I could shut it off it shut itself off.

Checked the fan, cranked it by hand a couple of times to see if in fact the fan was striking something or the engine was frozen. That was ok.

I took off the magneto to see if the new seal was in place and to check the rotor to make sure it was intact. No problems.

Started up the tractor; again a horrible clanking sound from the front and before I could shut it off it shut itself off.

While I was checking the carb to see if a screw came loose and was sucked up into the engine (all screws accounted for), I remembered that when I took off the governor, I also flipped the generator out of the way and lost the spacer washer.

Lost as in I looked for it for a while while I was putting everything together and couldn't find it. (I don't remember putting it down anywhere)

A lost spacer washer in the front housing might cause my noise issue.(???)

so...
1. Is there a way to confirm theory? (short of taking off front cover)
2. Is there a way to retrieve washer? (short of taking off front cover)

John

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Re: Bad compression

Postby eiebe » Fri Feb 10, 2017 8:50 pm

Not to highjack this thread but What is considered "new" compression? Like off the showroom floor I know 100lbs is "good".

ParlowMillFarm
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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 Feb 10, 2017 10:10 pm

Hey eiebe,

You can hijack my thread if you come pull off my front pully tomorrow :lol:

The service manual, GSS-1411, which you can get through this site, gives 120 lbs, at cranking speed, for new compression.

John

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Glen
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Tractors Owned: 1956 Farmall Cub with Fast Hitch, F-11 plow, Disc, Cultivator, Cub-22 mower
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Location: Wa.

Re: Bad compression

Postby Glen » Sat Feb 11, 2017 12:48 am

Hi,
I guess nobody replied to you John. Without being there to hear the engine run, I don't know what the noise is. Maybe someone has an idea. :)

ParlowMillFarm
5+ Years
5+ Years
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 » Sat Feb 11, 2017 9:32 am

Thanks Glen,

At this point I'm removing the front cover hoping I find a washer in there. Then all I'll need are some new gaskets to get back in business ( already on order)

John

eiebe
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Re: Bad compression

Postby eiebe » Sat Feb 11, 2017 2:13 pm

ParlowMillFarm wrote:Hey eiebe,

You can hijack my thread if you come pull off my front pully tomorrow :lol:

The service manual, GSS-1411, which you can get through this site, gives 120 lbs, at cranking speed, for new compression.

John


Awesome I have a service manual but it is vague if you were closer I'd love to pull that pully

ParlowMillFarm
5+ Years
5+ Years
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 » Sat Feb 11, 2017 2:45 pm

image.png
From GS-1411


This is from the manual. I just read on a different post that the domed Pistons can jack this up. Maybe someone can tell us to what.

John

ParlowMillFarm
5+ Years
5+ Years
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 » Tue Feb 21, 2017 6:19 pm

Update:

As I mentioned I had a bad rattling sound.

I removed the front cover looking for a lost washer. No washer.
I removed the oil pan. No washer.

I removed the hydraulic pump and left the fan assembly off and started the engine. After several false starts due to a poorly placed oil filter gasket, start up with no rattle. :{_}:

I put the hydraulic pump back on, start up, no rattle. :{_}:

Leaves the fan assembly as a culprit. I did place a metal overflow tube between the radiator and the fan during waiting on the rebuild. This does not contact during hand cranking. Could the minuscule amount the fan flexes during use be hitting my new tube?

John

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Re: Bad compression

Postby Jim Becker » Tue Feb 21, 2017 6:25 pm

ParlowMillFarm wrote:Could the minuscule amount the fan flexes during use be hitting my new tube?

If it does, you should be able to see a tiny shiny spot on the tube.


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