Intermittent poor running on my 129

three4rd · #1 12-02-2017, 10:47 PM

Some of you guys have been through the (now closed) threads on all this, and I really didn't expect to come back here again after what took place with some of my posts, but I thought I should check back in for any further advice.

The debate rages on as to whether I should keep my 129 or buy a new XT3 model (which is probably the best model out there at this point?). As I believe I mentioned awhile back, my brother took the cub down to his shop to work on it. The one thing they discovered almost immediately is that the carb was shot, and so bought a new one and put it in. Along with a few other non-engine-related issues that they found and repaired, they then said it seemed to be running great. In fact, my brother felt so confident about it that he was getting ready to load it on his trailer to bring back to me and then just like that when he started it to drive it on the trailer it was running as poorly as it did this summer. His description matches exactly what I was seeing a few months ago - that it simply has no power. So I suspect it may well be a case of his simply not having had it long enough to see the pattern that has emerged over the past year or so - that of it running fine one moment and not fine the next. Points are new, properly gapped, and basically all new electrical components...all this stuff was described in my previous threads so I won't go back into it all.

At this point, he'd like to disconnect the ACR system and get a compression reading on it, as well as possibly check the valves. The problem is, they really don't have much time at the present or foreseeable future to do anymore with the cub.

We've discussed the option of getting a remanufactured short block (or would it be a long block?) from this Kustom company that was recommended to me here. A question that remains in my mind at least, not being a mechanic, is - what other components are there besides what I'd get with a rebuilt engine that might be causing running problems? If components extraneous to what I'd get from Kustom are causing the problem and simply get bolted back on to the new block, then won't the same sort of problems still be there? If putting in a rebuilt engine might possibly still not improve the running condition all that much due to some other weird problem that is taking place, then I guess it'd be better to buy a new tractor. I've been looking at the top-of-the-line cubs - the XT3 series. All I can say is, for $4-5k, I would hope that something like that should last longer than 3 years, which is about the lifespan that everyone is telling me new machines have. IF I could be guaranteed that putting the rebuilt engine in my 129 would basically restore it to running condition, I'd say let's go for it. I have little interest in buying a new tractor simply for the sake of buying a new tractor. This is why I still drive a '95 Riviera that is on its third engine I suppose. The guy at Kustom indicated that they stopped repairing tractors (even fairly new ones) cause they got tired of people bringing them in frustrated that their 3-year old tractors already stopped working, along with complaining to the shop about it.

Any further thoughts on this situation please let me know, as I really am not certain which way I want to go with this. Besides the puzzling intermittent poor running, I also have the leak in the transmission that has been there for years - hasn't really gotten any worse so I just keep adding fluid. And, it goes through right front wheel bearings. The oil pan drain bolt has issues too - I try not to ever use it (have an oil extractor instead). This is like the 3rd bolt that's in there - the previous one was stripped and so I had put in an oversized tapered bolt that has been working well but seemed to be a bit looser than usual a few months ago. I had noticed some oil dripping from it...tightened it up and seemed to be ok. This was just a bit before my brother took the tractor. And, one final issue is that the mower deck spindles aren't getting any younger either! There is a good amount of play in that center spindle. So, see what I mean? All in all, repairing it would still involve putting a rebuilt engine in a tractor and accessories that are all 40+ years old. Cost effective or not? I used to consider it a no-brainer to try and keep the old 129 running, but now am just not certain about it. Might this old tractor simply be pretty well 'used up' by now?

J-Mech · #2 12-02-2017, 10:59 PM

Here is the closed thread the OP is talking about:
http://www.onlycubcadets.net/forum/s...ad.php?t=49877

Dude, we beat a dead horse with you on this already. Not really sure I want to get into that ring again.

Did you actually do any of the things we suggested before? Has the head been cleaned and properly torqued? Did your bro clean out the fuel system? Does it have a new condenser on it? Did anyone pull the valves out and clean the guide and valve stem?

I really think after all we went through with you on this, and the fact that you seemed to think we are all a bunch of jerks, maybe it best for you to just put the tractor up for sale and go buy a new XT3 and be happy.... for a few years.

olds45512 · #3 12-02-2017, 11:02 PM

Quote:

Originally Posted by J-Mech

Here is the closed thread the OP is talking about:
http://www.onlycubcadets.net/forum/s...ad.php?t=49877

Dude, we beat a dead horse with you on this already. Not really sure I want to get into that ring again.

Did you actually do any of the things we suggested before? Has the head been cleaned and properly torqued? Did your bro clean out the fuel system? Does it have a new condenser on it? Did anyone pull the valves out and clean the guide and valve stem?

I really think after all we went through with you on this, and the fact that you seemed to think we are all a bunch of jerks, maybe it best for you to just put the tractor up for sale and go buy a new XT3 and be happy.... for a few years.

Have you ever thought about getting a job in public relations?

olds45512 · #4 12-02-2017, 11:42 PM

Does the engine smoke? If so, how bad? Unless it's smoking like a freight train then i doubt it's a compression issue. You say the carb is new and didn't change the issue so i think we can rule that out. I would suggest removing the line from the carb and turning the fuel on, gas should run out like you're taking a pi$$, any less than that and it might be starving for fuel.

olds45512 · #5 12-02-2017, 11:56 PM

IH sold Cub Cadet in 1981. Mtd is generally known for making poor quality equipment for homeowners that would rather throw it away and buy a new one rather than make repairs, sadly we live in a world where people want cheap over quality. While i agree that the XT3 will never be the quality of the older Cub's i will say that i would buy one if i had money to burn.

olds45512 · #6 12-03-2017, 12:18 AM

Quote:

Originally Posted by J-Mech

What type of inline fuel filter?

That was my next question, I guess great minds think alike.

john hall · #7 12-03-2017, 07:40 AM

I like the idea of suspicioning the fuel filter. For giggles, since the carb is NEW, and if the tank has been properly cleaned, there should be no need for a filter--remove it and see if the problem goes away. Or replace it with something else--We've added lots of inline filter to various machines over the years, lawn mowers to farm equipment--clean fuel is good!

If the condenser and coil are old, replace them. I wouldn't bother trying to "test". If you are considering spending big $$ for a new machine, $50 should get you both of those and they are simple enough to change.

How about the wiring? Is something frayed or corroded causing intermittent issues? Low voltage to the coil....

If the wiring is suspect I'd replace it. That harness should be simple enough that you could make your own for cheap. Later, you could see if a reproduction is available, if the problem goes away.

Jmech mentioned a valve. Yep, dirty scored, weak spring--all could make it "lazy". If you don't want to (or aren't equipped to) remove and clean the stems and guides, try adding some Marvel Mystery oil to the gas. Yeah the EPA and the neigbors will love you as its going to smoke. Its an old trick to help with sluggish valves. If the problem goes away--you probably need to go ahead and remove the valves and polish. Marvel mystery oil is more of a bandaid, not the required surgery.

Good Luck!

ironman · #8 12-03-2017, 08:21 AM

Quote:

Originally Posted by three4rd

Tim...LOL about taking a...well..you know. I had replaced the fuel line, cleaned out the tank real good, and also installed an inline fuel filter. Engine doesn't really smoke - but does have some blow-by (not real noticeable though). Uses a good amount of oil as I mentioned awhile back. My brother had asked the same thing about a possible reduction in fuel flow, and we thought a filter might not be a bad idea. The tank did have some dirt inside it, the petcock screen was junk, and so I got rid of that.

I cast my vote with the "sounds like fuel starvation" group. Have you checked the vent hole in the gas tank cap for blockage. If enough air can't get in the tank to let fuel flow out freely, your motor will run like crap or even die. I've seen it multiple times. To test, simply loosen the cap and drive it around.

My vote on a new tractor is this: If you have the money and spending it it is not a problem then go for it. Obviously this older tractor has given you a lot of frustration so why continue asking for more. Besides, with the additional factors that you mentioned that have to be addressed it sounds like you are more in need of a total restoration not just getting the engine running.

On the "3 years and junk it opinions", I don't buy it. I agree that today's new stuff ain't made like it used to be but there is no reason why with any amount of reasonable maintenance that any brand's POS won't last 10 years unless you are overworking it.

sawdustdad · #9 12-03-2017, 08:40 AM

My initial thought was fuel starvation. clean out tank and replace fuel pickup screen/valve at the tank.

If engine is not smoking badly, it's not likely a compression issue. A stuck valve, as Jon has already mentioned is another possibility.

When it starts to run badly, pull out the choke a bit. If that helps, then you've got a fuel supply issue. If it makes no difference, then pursue the condenser, coil, valves.

Terry C · #10 12-03-2017, 11:56 AM

I think when we tell people to rebuild rather than buying new ones they are missing the picture. Yes a new machine will last longer than three years, but if you invest 1/2 of the price of a new machine into rebuilding the old one, they would end up with a tractor that will outlast the new one.
If you don’t like doing the work of rebuilding then by all means buy a new one.
But don’t expect us to praise you and tell you made a good move. We have the history of well built machines to back up our advice. Rebuilding gets you more for less money period, this fact cannot be disputed. I have a shed full of proof.

That’s not just my opinion it’s fact.