JD 450 running a bit ragged

[little1406]

I've got a JD 450 track loader that runs just fine when first started but, after a while, starts running somewhat ragged. If it was a gas engine, I'd say it was running too rich, causing it to miss occasionally, etc. But it's a diesel, the 202 cu in 4-cylinder engine that JD used in these models (1970's...?)

The other diesels I have (my Dodge truck, and a little Kubota tractor) never behave this way.

What could be wrong with this JD diesel?

Thanks

 

[Dutch445]

any background on the machine? have you had it right along? any service info, last time any filters have been changed?
fuel quality been checked?
there's a lot more to know before anybody can really offer a starting point,
it could be an injection problem, either the pump or a bad injector, or bad fuel, or any host of problems....

 

[jenkinsph]

I agree with Dutch and suggest you start by checking the simple things like filters, trash in tank. Then move towards injectors, injector pump. How about the crankcase vent tube do you have much blow by? My 450 dozer finally had so much blowby I had to stop in the middle of building a pond and replace pistons and liners.