450 Diesel carb

[Redpaint11]

I have 2 450 diesels. One starts on gas and runs smoothly with no issues. When I start the other one it has trouble idling and sometimes dies. The exhaust is extremely rich and black. I considered cleaning and rebuilding it but it seems like I’m just guessing at this point. If anyone has seen this please let me know what you did to fix it.

 

[Janicholson]

I have 2 450 diesels. One starts on gas and runs smoothly with no issues. When I start the other one it has trouble idling and sometimes dies. The exhaust is extremely rich and black. I considered cleaning and rebuilding it but it seems like I’m just guessing at this point. If anyone has seen this please let me know what you did to fix it.

Is the choke stuck on the rich one? look into the inlet and check that. The float could be too high causing over rich mix. The air cleaner could be plugged causing excess suction. Jim

 

[Redpaint11]

Good tips. I will check it out and report back. Thanks

 

[rustred]

Good tips. I will check it out and report back. Thanks

check your float, it might be heavy.

 

[Redpaint11]

When you say “heavy” what does that mean?

 

[DaveBN]

I think he is referring to the float being full of gasoline, that's called Water Logged. That causes the float to ride lower than it should thus causing more gas in the carburetor bowel this causing too rich a mixture of air and gas. Typical test for this is to shake the float and listen for fluid sloshing around inside of it.
Dave

 

[Redpaint11]

I thought that might be it. Thanks

 

[DeltaRed]

My 450D ewas doing that.Severly flooding.
Black smoke,barely run enough to get the diesel started. There was 'crap' in the needle/seat,not closeing. Simply cleaned out the crap and it starts/runs as should.

 

[Redpaint11]

That makes sense. Time to take it apart and clean it.

 

[Redpaint11]

Ok. Here is what I found. Took the carb float bowl off. Cleaned screen and needle valve on the float. There was some debris in the screen. I also sprayed carb cleaner up in the rest of the parts that were visible. Put everything back together and still had the issue. I then took the oil bath bowl off of the air cleaner. The center bowl is full of oil as is the outer bowl. I started and ran the tractor without the oil bath installed. It started and ran perfectly. Now I’m wondering if the carb was sucking oil or just not getting enough air.
Please weigh in on that. Thanks

 

[used red MN]

No real experience diagnosing an oil bath air filter, but thinking about it here is what I would try. With the oil cup off hold your shop vac up to the hose or pipe that supplies the engine. Judge how much suction it is creating to get an idea of how much restriction it might be creating. You say you have two 450Ds compare one to the other. First look down the tube that comes through the hood to make sure it is not blocked.

 

[wore out]

Ok. Here is what I found. Took the carb float bowl off. Cleaned screen and needle valve on the float. There was some debris in the screen. I also sprayed carb cleaner up in the rest of the parts that were visible. Put everything back together and still had the issue. I then took the oil bath bowl off of the air cleaner. The center bowl is full of oil as is the outer bowl. I started and ran the tractor without the oil bath installed. It started and ran perfectly. Now I’m wondering if the carb was sucking oil or just not getting enough air.
Please weigh in on that. Thanks

Is the inlet side of the air cleaner possibly clogged with dirt, debris, or a mud dauber or rodent nest?

 

[Redpaint11]

That will be my next thing to check. I assume by the responses I’m getting that there should be oil in the center bowl.

 

[Brownie450]

Have you emptied the oil out of the cup? Dirty mess
to clean out a cup, but if it has dirt built up in the
cup bottom, it will cause your problem.
Jim

 

[Janicholson]

That will be my next thing to check. I assume by the responses I’m getting that there should be oil in the center bowl.

The metal mesh above the oil is often so coated with dirt that has been taken out of the air. that it no longer passes enough air. The reason I discussed the intake in my earlier post. Cleaning it is painful. Removing the entire cleaner, plugging the inlet/outlet. turning it upside down and filling it with diesel, or solvent, and putting the cup back on, then shaking it to loosen and clean the mesh. Jim

 

[Redpaint11]

I’m used to the hard way being the right way. I will get it done and post the results.
Thanks again for all of the advice

 

[Farmalldude45]

The metal mesh above the oil is often so coated with dirt that has been taken out of the air. that it no longer passes enough air. The reason I discussed the intake in my earlier post. Cleaning it is painful. Removing the entire cleaner, plugging the inlet/outlet. turning it upside down and filling it with diesel, or solvent, and putting the cup back on, then shaking it to loosen and clean the mesh. Jim

If problem is resolved by removing cup, plugged filter mesh is not problem. Check inlet into filter for obstruction.

 

[Redpaint11]

Ok guys,
Thanks for all of the suggestions. I cleaned the carb bowl and screen. Removed and serviced the oil bath and the entire housing. Put everything back together and she’s running much much better. Probably still a little rich compared to the other one but completely operable now.

 

[rustred]

Ok. Here is what I found. Took the carb float bowl off. Cleaned screen and needle valve on the float. There was some debris in the screen. I also sprayed carb cleaner up in the rest of the parts that were visible. Put everything back together and still had the issue. I then took the oil bath bowl off of the air cleaner. The center bowl is full of oil as is the outer bowl. I started and ran the tractor without the oil bath installed. It started and ran perfectly. Now I’m wondering if the carb was sucking oil or just not getting enough air.
Please weigh in on that. Thanks

no mention on the float ?? no it dont suck oil. there is an oil line on the cup. use any oil except gear on depending on weather. hyd oil, engine oil dont matter. the book says to use the same oil as the engine which would be 15-40 but in winter 10 wt is good. plus some of these tractors run rich when cold and some need a lot of choke to start them. they speed up as they warm up. i think thats why so many hated the gas starts. u had to be an engineer to start them. but it was one of the very best ways to start a diesel engine. cat used this and so did john deere but they had a separate engine to warm the diesel engine but it worked well also.

That will be my next thing to check. I assume by the responses I’m getting that there should be oil in the center bowl.

yes thats why there is a little hole in the centre part. oil level is all the same to the outer line.