1250 Coming to a crawl / stalling out under load

[martyrant]

It's been a while since I've been on here but poked around briefly before posting this and noticed a lot of familiar faces still posting, so hello to everyone again.

I had someone rebuild the engine in my 1250 a couple years ago and once I got it back in the tractor and hooked it up, things looked good until I started to try to use it like I normally would (beat the hell out of it, put it through the runner, etc.) and it would begin to crawl, then eventually stall out.

I feel like this is a self-inflicted problem and honestly hadn't gone back to it until recently when I had some time, so I got it running again today, fixed my silly PTO issue (one of the cables running to a fuse fell off the spade connector), and started to get something hooked up to it to test with (threw a agrifab rake on it for now), realized my hydraulic levers are frozen and need to go about getting those freed up, but on to the issue:

I can't remember if it really had this much thrashing/movement to it at idle [I do know the exhaust hood is missing some screws that adds to the drama on the thrashing], but it goes away a bit at higher throttle, however I noticed it throttling up/down just sitting there, opened the hood and noticed it was doing just that. I've messed with the throttle cable a couple times to shorten it up/lengthen it and still have this issue, but I think this would also cause some issues when I'm actually trying to use it (leveling the driveway with the box blade would even stall it after about 15-20 feet).

Would this most likely be the cause of my woes? Any good ideas on how to fix this? I feel like I may have reassembled it wrong, I noticed the spring at the bottom when the throttle is at low is slack, though it is taut when at high throttle.

Video of it running and me putting my finger on the throttle to hold it there:

https://goo.gl/photos/HaTVY4hboTGhgg8M8

Going to try and figure it out tomorrow as it's getting dark now, but I have a feeling this is at least the start of fixing the issues.

Thanks in advance for any insight.

[DeltaCub]

QuietLines Shake! However, when you had the engine out did you replace the engine mounts? Did you do the cradle mod? I have found that the OEM mounts work the nicest to reduce vibration if adjusted properly. I am however, going to use solid mounts on my next overhaul (1650).

[DeltaCub]

I clicked on the video link you provided but it has no sound. I am curious to what extent was the rebuild? Did you or the rebuilder set the timing? Was the carb rebuilt and adjusted after the engine was warm and were you using fresh fuel?

[martyrant]

Originally Posted by DeltaCub

QuietLines Shake! However, when you had the engine out did you replace the engine mounts? Did you do the cradle mod? I have found that the OEM mounts work the nicest to reduce vibration if adjusted properly. I am however, going to use solid mounts on my next overhaul (1650).

I did replace the mounts before putting it back in. I think I used a pack I got off ebay. Not sure what the cradle mod is, so nope on that one.

[martyrant]

Originally Posted by DeltaCub

I clicked on the video link you provided but it has no sound. I am curious to what extent was the rebuild? Did you or the rebuilder set the timing? Was the carb rebuilt and adjusted after the engine was warm and were you using fresh fuel?

Sound works for me, but I'll upload it somewhere else in a bit in case. Pretty sure it was just the gaskets / oil pan on the rebuild. It does sound fine IF the throttle isn't moving all over the place...so like I said, I'm guessing that's my problem but would not know if that would cause stalling issues (most likely would if there's no power and its trying to do something...)

[martyrant]

Alright so took another look this morning, was able to get the hydraulic controls working easily enough with some penetrating oil on the bright side, on to the issue at hand:

Found that the fuel hose is rubbing a little at WOT, but I don't think that's the issue. Need to put a filter in there anyway, so grabbing that when I go to town today just to lengthen it up and get it out of the way.

The spring does need to be shortened I think as it's not quite taut, however I did find the following issues:

Had to keep the choke in the position you see in the picture to keep it running well at WOT, so probably need to adjust the carb a bit (? not sure, not very good with that stuff), but my main concern was when I shut the thing off some wisps of white smoke pour out of the carb intake. Would that be timing like you said Delta? Or is that a product of it running too rich or lean?

Picture should be attached as well (showing position of choke to keep it running)

[DeltaCub]

Originally Posted by martyrant

Alright so took another look this morning, was able to get the hydraulic controls working easily enough with some penetrating oil on the bright side, on to the issue at hand:

Found that the fuel hose is rubbing a little at WOT, but I don't think that's the issue. Need to put a filter in there anyway, so grabbing that when I go to town today just to lengthen it up and get it out of the way.

The spring does need to be shortened I think as it's not quite taut, however I did find the following issues:

Had to keep the choke in the position you see in the picture to keep it running well at WOT, so probably need to adjust the carb a bit (? not sure, not very good with that stuff), but my main concern was when I shut the thing off some wisps of white smoke pour out of the carb intake. Would that be timing like you said Delta? Or is that a product of it running too rich or lean?

Picture should be attached as well (showing position of choke to keep it running)

1) Happy you were able to free up the dual stick controls!

2)If you are referring to the long spring below the carb...it can have slack at idle. Download the Kohler engine manual to see throttle and governor adjustment procedures including WOT speed.

3) You may want to have the carb cleaned or do it yourself if you are mechanically inclined,,,,again refer to Kohler K-Series engine manual.

4) Little wiffs of white smoke or normal at shut off especially if you shut off engine at higher speeds. These carbs do not have fuel shut-off solenoids like modern, EPA compliant carbs.

5) Timing again refer to Kohler K-Series manual.

[DeltaCub]

http://www.kohlerengines.com/onlinec...df/tp_2379.pdf

[DeltaCub]

http://www.onlycubcadets.net/forum/s...ead.php?t=4630

Engine cradle modification link.

[martyrant]

Originally Posted by DeltaCub

1) Happy you were able to free up the dual stick controls!

2)If you are referring to the long spring below the carb...it can have slack at idle. Download the Kohler engine manual to see throttle and governor adjustment procedures including WOT speed.

3) You may want to have the carb cleaned or do it yourself if you are mechanically inclined,,,,again refer to Kohler K-Series engine manual.

4) Little wiffs of white smoke or normal at shut off especially if you shut off engine at higher speeds. These carbs do not have fuel shut-off solenoids like modern, EPA compliant carbs.

5) Timing again refer to Kohler K-Series manual.

Thank you, spent some time today tinkering and things were going pretty well for a little over an hour of use after I printed section 6 of that manual and followed the instructions for setting the needles.

I didn't clean the carb, and due to the instructions saying to put a load on the motor while adjusting the needle in step 4 there, I changed over to the rototiller and turned on the PTO while I set that.

I had the tiller on so why not do the garden since the wife was asking me about it and that was one of the reasons I started looking at this again. Was able to till the thing and was doing one last clean pass along some grass, ran it to the end and the ground turns pretty hard/rocky (it's where I haven't tilled in past years) so the thing just stalled and turned off rather abruptly. Figured that was a sign that I was done for the day and started up the hill with the PTO off, half speed, and the thing just stalled abruptly again.

Figured at this point something serious was probably wrong so I wanted to leave it but it was on a hill and rather than just let it drift back down I started it again and got it to the top and shut it off.

It was not acting like before where it would get all sluggish (struggling) and stall though, both times it just abruptly turned off -- not sure if it's an overheating issue now?

They are just small wisps of white smoke, so I'll take it that is normal.

(Yes I know I should have a belt cover on the tiller)