Continued engine problems with my 129 - Page 5

ol'George · #41 09-03-2017, 08:47 AM

Mom used to say that in German,---- it sounded better that way.

(She also was from PA.)

cadzag72 · #42 09-03-2017, 02:10 PM

I haven't been through all the other threads in their entirety, but I have an idea that may help. It's really cheap, too. I was thinking perhaps if the engine is cranking harder with the choke out, and has very little power, it may be as simple as you having a clogged air filter. I had one come through the ranks that when I picked it up, it would run but always sound like it was fighting itself to stay running, and engaging the deck would almost kill the engine. I pulled the air cleaner cover, and sure enough, packed solid with who knows how many years of crud. It's easy to check and cheap to replace, and should save you some headaches. If someone has already mentioned this in the other threads, then my apologies, and best of luck getting it sorted! If you feel overwhelmed, getting help is never a bad thing.

three4rd · #43 09-03-2017, 03:07 PM

Quote:

Originally Posted by cadzag72

I haven't been through all the other threads in their entirety, but I have an idea that may help. It's really cheap, too. I was thinking perhaps if the engine is cranking harder with the choke out, and has very little power, it may be as simple as you having a clogged air filter. I had one come through the ranks that when I picked it up, it would run but always sound like it was fighting itself to stay running, and engaging the deck would almost kill the engine. I pulled the air cleaner cover, and sure enough, packed solid with who knows how many years of crud. It's easy to check and cheap to replace, and should save you some headaches. If someone has already mentioned this in the other threads, then my apologies, and best of luck getting it sorted! If you feel overwhelmed, getting help is never a bad thing.

Thanks for the suggestion but I had replaced the air cleaner just a few weeks ago and also I take it out frequently and use the air compressor on it to blow it out. I don't let them go too long...used to but of late I've been replacing them fairly frequently.

three4rd · #44 09-03-2017, 03:08 PM

Quote:

Originally Posted by ol'George

Mom used to say that in German,---- it sounded better that way.

(She also was from PA.)

LOL...yes...I live in the heart of PA Dutch Country so I've heard plenty of that dialect over the years! Wish I could speak it...sort of dying out unfortunately as the younger generations come along.

three4rd · #45 09-03-2017, 03:26 PM

Not sure if I mentioned this before, being that there have been so (more like too) many threads and posts lately about my Cub. But...when it runs it seems the governor is always chasing. The engine speed is erratic and unsteady. I'm guessing that this would have more to do with carburetion than timing? It all ties in with the loss of power I suppose. AND...I noticed last night that most of the head bolts weren't tight at all - so I tightened all of them up. At least I think these are the head bolts - about 6 of them right on top of the engine (?) Either way, I'm betting they shouldn't be anywhere near as loose as they were.

Just looked at the service manual after posting the above...There appear to be 9 head bolts. Some must be under engine shrouding. I should probably pull off what tin I need to and check the other 3 bolts (?) The 6 I tightened up were places where there were bolt holes in the shroud.

Alvy · #46 09-03-2017, 05:18 PM

Yes that's a big problem. Time to take the head off and flatten it, new head gasket after cleaning/decarbon the valves, top of the piston etc.

J-Mech · #47 09-03-2017, 07:10 PM

Quote:

Originally Posted by three4rd

Not sure if I mentioned this before, being that there have been so (more like too) many threads and posts lately about my Cub. But...when it runs it seems the governor is always chasing. The engine speed is erratic and unsteady. I'm guessing that this would have more to do with carburetion than timing? It all ties in with the loss of power I suppose. AND...I noticed last night that most of the head bolts weren't tight at all - so I tightened all of them up. At least I think these are the head bolts - about 6 of them right on top of the engine (?) Either way, I'm betting they shouldn't be anywhere near as loose as they were.

Just looked at the service manual after posting the above...There appear to be 9 head bolts. Some must be under engine shrouding. I should probably pull off what tin I need to and check the other 3 bolts (?) The 6 I tightened up were places where there were bolt holes in the shroud.

Did you torque them with a torque wrench?

Loose head bolts may be part of your problem. That would make it have low compression, and burn oil.

three4rd · #48 09-03-2017, 08:28 PM

Did not torque...I could easily go back and do that. Actually, I got so intrigued once I had the shroud off and could access all the bolts that I decided to take off the head to see how things looked. It was fun and exciting - having never had it off before! Once I had it off, it made me want to keep going! I'd love to rip into the whole thing now after getting a small taste of it.

Anyway, I have no idea if this will be helpful or not to ascertain the condition, but here are some pics I took. Certainly the gasket looks ok to me, but let me know what you think. Piston and cylinder seem alright too.

three4rd · #49 09-03-2017, 08:34 PM

Quote:

Originally Posted by Alvy

Yes that's a big problem. Time to take the head off and flatten it, new head gasket after cleaning/decarbon the valves, too of the piston etc.

What is a big problem...that the bolts were loose? Or that my pictures indicate issues that need to be addressed? Not sure what you're referring to. I did not do any carbon scraping - was worried about screwing up the gasket. I was really tempted to at least scrape the carbon off the top of the piston but was just hesitant due to maybe getting dirt down inside the cylinder. Unless I'd actually take the valves out and do everything that should be done, I figure just doing some scraping really wouldn't make that much difference, would it?

Alvy · #50 09-03-2017, 09:41 PM

Quote:

Originally Posted by three4rd

What is a big problem...that the bolts were loose? Or that my pictures indicate issues that need to be addressed? Not sure what you're referring to. I did not do any carbon scraping - was worried about screwing up the gasket. I was really tempted to at least scrape the carbon off the top of the piston but was just hesitant due to maybe getting dirt down inside the cylinder. Unless I'd actually take the valves out and do everything that should be done, I figure just doing some scraping really wouldn't make that much difference, would it?

Well I phrased it wrong. I meant that it definately needs to be addressed because loose head bolts will cause all of your symptoms as Jon said. You posted pictures after I posted. Just bring the piston to the top and clean away. Get the whole area super clean as well as clean and flatten the head. New gasket, get a torque wrench and follow the torque sequence.

Time to watch the body man extraordinaire video as well

http://www.onlycubcadets.net/forum/s...ad.php?t=45286