Mini Swamp Buggy (base YM146) Help!

[EMP124]

I Recently acquired a mini swamp buggy, built from what I believe to be a mid 80's YM146.. it has a Yanmar 2T 75U-N diesel engine... It has been sitting for a few years... the previous owner was able to show me it would crank, he got it to fire off once for about 5 seconds before it died, after that nothing but cranking. This is my first diesel engine ive worked on. I am familiar with the Fuel Bleeding process and will attempt this first. my concerns are finding parts for this engine, seems to be a rare one. Are there places to order parts such as fuel injection pumps and more? any info on what to do besides draining.cleaning,and primeing the fuel system? any info on this beast would be very helpful. Thanks

 

[dex3361]

Welcome to TBN. Post some pics of this machine and you will get some good advice here.

 

[bdeboer]

Hoye tractor has a website for yanmar parts. My 2402D Yanmar has a bleeder valve right on the fuel filter.

 

[tachnem]

Pics!

 

[EMP124]

Pictures soon, so i bled the fuel system. and gave it a crank... fired right up.. tons of black smoke... ran at a high rpm for about 3 mins.. then shut off.... i can get it to fire up but after a few mins it will die again... no throttle response at all either starter decided to bite the dust as well. i will have it rebuilt this weekend and give it another go... any ideas?

 

[aczlan]

Check your air and fuel filters, then check that your fuel tank vent isnt plugged.
Were you able to change the RPM while it was running?

Aaron Z

 

[EMP124]

No I couldn't change RPM at all... new fuel filter. air filter seems good n clean, can tell it was replaced recently

 

[Dozernut]

Could be crud accumulated while the buggy sat and has plugged your fuel tank screen. If you already have checked this then ignore.

 

[EMP124]

so while i'm waiting to get the starter repaired... I removed every fuel line and filter and pump.... I cleaned them all very well... I was surprised to see what I flushed out looked like very dirty motor oil anyways got them all cleaned up... replaced a few hoses and will try again when I get the starter. I have my fingers crossed!

 

[zing]

No I couldn't change RPM at all... new fuel filter. air filter seems good n clean, can tell it was replaced recently

Running at high RPM with no control from the throttle probably means that your diesel is running away, especially since you can see what looks like black crankcase oil in your fuel system and the exhaust is really black. I had that happen once on a fishing boat with a cracked injector. The crankcase filled with diesel and then it got fed back into the engine and the engine ran wide open. I even shut off the fuel line and it still ran wide open. It only stopped when I blocked off the air supply. Very luck it didn't blow the engine. It can happen for various reasons (Google "runaway diesel") but basically it looks like you have fuel getting into your crankcase from somewhere, and creating a loop where the engine runs on crankcase oil.

It depends on how handy (and thrifty) you are, but I would suggest that you need someone with some experience with diesel engine repair to help you find the problem. It should be fixable though.