129 Engine Repair Help Needed

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PTWannaHave
Posts: 295
Joined: Wed Apr 11, 2012 12:39 pm
First and Last Name: Ben Michaud
Location: Richmond, Ontario

Re: 129 Engine Repair Help Needed

Post by PTWannaHave »

strap to hold flywheel while torqueing it
strap to hold flywheel while torqueing it
20180209_173534.jpg (1.29 MiB) Viewed 4095 times
This might be useful for someone... I found this method to work well to hold the flywheel while I was torqueing it to spec.
PTWannaHave

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dag1450
Posts: 2356
Joined: Fri Apr 01, 2011 3:16 pm
First and Last Name: Dave Gibson
Location: Chalfont, Pa

Re: 129 Engine Repair Help Needed

Post by dag1450 »

That's exciting!! Great job!! As to the carb....have u used this carburetor before to know that it's ok? Have u gone through the carb to clean it up inside. That's maybe a place to start.
127, 1650, 1572, 1872, 2072 . A mower, blower and blade for each.

Klapatta
Posts: 1352
Joined: Mon Sep 06, 2010 2:25 pm
First and Last Name: Kenneth LaPatta
Location: Rockingham VT.

Re: 129 Engine Repair Help Needed

Post by Klapatta »

It sure does! A home made wrench from scrap steel will get the job done too.
DSCN7692.JPG
DSCN7692.JPG (276.2 KiB) Viewed 4085 times
With this one I have to slip on the socket first before bolting it on.
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DSCN7694.JPG (357.51 KiB) Viewed 4085 times

PTWannaHave
Posts: 295
Joined: Wed Apr 11, 2012 12:39 pm
First and Last Name: Ben Michaud
Location: Richmond, Ontario

Re: 129 Engine Repair Help Needed

Post by PTWannaHave »

dag1450 wrote:That's exciting!! Great job!! As to the carb....have u used this carburetor before to know that it's ok? Have u gone through the carb to clean it up inside. That's maybe a place to start.
Good point Dave; I should have mentioned that I completely went through the carb, without disassembling the throttle & choke shafts. (I don't think I could've gotten it any cleaner even if I had...) I purchased the tractor in very rough running condition, so the carb was 'working' before I parked and disassembled the machine. I thoroughly disassembled every other carb part and cleaned, and put new fuel bowl gaskets (2) and new fuel bowl needle (since I had one).

I'm guessing the only way to identify this carb as the culprit would be to put another known-to-be-perfect carb... (In my case, that would mean buying a new one.)
PTWannaHave

PTWannaHave
Posts: 295
Joined: Wed Apr 11, 2012 12:39 pm
First and Last Name: Ben Michaud
Location: Richmond, Ontario

Re: 129 Engine Repair Help Needed

Post by PTWannaHave »

OK; I refilled with fresh oil (SAE30 non-detergent), and played around with it some more... A friend of mine mentioned I should put the air filter on, as some carbs cannot be fine-tuned otherwise. I have a fancy Spectre cone filter for this machine; didn't make a difference.

As you can see in the pic, both clean plugs ended up with a consistent look after about 10-15mins each of varying engine speeds. Seems like a combination of carbon build-up and wetness. Not sure if the latter is fuel, or fuel & oil...
dirty plugs
dirty plugs
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Engine compression is 90psi; what should it be?

If one did not see all the exhaust smoke and only heard the engine, they are likely to think it is a fine-running engine... But alas, the smoke and plugs indicate otherwise. Also, I think I 'lost' 1/4 of a quart of oil...! I'll have to keep a closer eye on that, but it would explain all the smoke...

As previously mentioned, I have new piston rings, which would be a bummer if excessive oil is getting by and being burned... If that is the case, does the 90psi measurement make sense?

No job is simple...!
PTWannaHave

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BigMike
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Joined: Mon Sep 06, 2010 8:45 pm
First and Last Name: Mike Andrews
Location: Niles,Michigan

Re: 129 Engine Repair Help Needed

Post by BigMike »

Ben, new rings need time to seat. The tractor needs to be put under good load and runs hard. The puts plenty of pressure on the rings to let them seat.
A plow day or a wooden pallet loaded and drug around will do just fine.

PTWannaHave
Posts: 295
Joined: Wed Apr 11, 2012 12:39 pm
First and Last Name: Ben Michaud
Location: Richmond, Ontario

Re: 129 Engine Repair Help Needed

Post by PTWannaHave »

Thanks Big Mike; I will endeavour to do that before doing anything else to try to rectify a problem that might not be a problem...
PTWannaHave

PTWannaHave
Posts: 295
Joined: Wed Apr 11, 2012 12:39 pm
First and Last Name: Ben Michaud
Location: Richmond, Ontario

Re: 129 Engine Repair Help Needed

Post by PTWannaHave »

20180325_150718.jpg
20180325_150718.jpg (1.43 MiB) Viewed 4063 times
'Running under load' to help/try to seat the piston rings... :D
PTWannaHave

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