Belarus 250AS decompression lever hard to move

[Caracal13]

Hello,

I have a Belarus 250AS that I am trying to get running and have a problem with the decompression lever. It is hard to move. At the engine case, I have to pry the rod backwards to the open compression so the engine will 'free-wheel' as it should. I then have to push the lever forward with my foot to close the system for compression. I hope that makes sense. It is functioning when I use this process, but the lever should move freely using the control lever. I have sprayed quite a bit of PB Blaster where the levers enter the engine case, but that has not loosed the levers to where the rod will move freely. Any thoughts on how to get the rod to move freely would be appreciated. Hopefully this does not mean 'cracking' the case.

Thanks,
Caracal13


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[phil25]

Another russian princess feeling "ill"..
Can you disconnect all the linkage at the engine and where it connects to the operating lever?
Maybe there is a rusted or worn operating lever in one of its support bushing?
try each individual lever at the engine to be sure if there only one or more lever actually seizing up?
does the lever move easy from the seated position, until the point of where compression is beginning to build? and then binds up? more so than normal "sweet spot? for full compression?
hope it helps

 

[Caracal13]

Phil,

Thank you for your reply. I have not pulled the lever assembly apart to where I can move each of the levers at the case. I will try that this coming weekend.

I cannot move the lever to the decompression position from the sitting position. The entire mechanism has to be pried into position from the case area. Once the lever is in the decompression position I can move it to the compression position, but I have to use my foot to move it to the compression position. The system works, but not as it should.

The tractor has not been started in 10-15 years. I had it running for 3 seconds this past Saturday, but then ran into another issue. I will go back this weekend and try again. Perhaps it will loosen up once it's running.

I will let you know what I find.

Thanks,
Caracal

 

[phil25]

It might be better to check all the levers/linkages first, just in case one of them gets bent from how you have to use it now?
these engines will run backwards if the compression is applied at the wrong time of the starting cycle, not a every time thing but can happen, lots of black smoke and noise.. especially since you can't ease the compression on as it rolls over.
also be sure to have a rag handy to block the air intake in case it starts and runs away, given the time of non use there might ???be internal injector pump issues.
hope it helps.

 

[Caracal13]

Thank you for the suggestions. I'll do that when I head up to work on it this coming weekend.

 

[phil25]

And again...i checked the manual here and it does not show the arrangement of how the decompression is done inside the engine, just how to operate it for cold temp starting. I can only guess that there is a mechanical operation of of the exhaust valve to hold it slightly open when starting, i am wondering if there is a stuck valve in its guide? or a bent valve push rod? it might again be a good thing to take the valve cover off and see what the operation does when de-compressing, you can roll the engine over with the crankshaft front pulley /nut to check a full sequence of operation.
still hope it helps

 

[Caracal13]

Phil,

Thank you for the suggestion. I disconnected the rod from the two levers and the rear lever movement is smooth. The front is sticky. I was able to get moving much better after pulling the side plate and squirting lubricant around the lever. It is still a little stiff, but I can move the rod from the seating position. Hopefully, it will move more freely as it is used. Thanks again.

Now I have another problem. See below. I'll also create another thread. Any thoughts on the below?

The hand and foot throttle controls do not change the engine RPM. The tractor will start, but it's a 'runaway'. I have to kill it by placing something over the intake and it will slowly starve the engine of air and it will then shut down. I pulled the back plate off the injector pump and the internal linkage in the pump moves freely while using the hand or foot controls. Any thoughts on why the throttle controls don't change the engine RPM?

Thanks,
Caracal