1996 873 lugs down and black smoke

[slewpumper]

I have a 1996 873 bobcat that has been an awesome machine for me. I do general repairs on this but no very little about the Duetz engine which it has. It bogs down and runs rough if I lugs down and starts running very rough if I try and dig with it. This weekend I rented a tree transplanter for it and it would bog down when I would try and run the spades into the ground. It seems to do it more when I have it reved all the way up. It did it a few times this winter also when I was pushing snow but I assumed then that it was bad fuel. Also when this happens it blows out alot of black smoke which tells me it is not getting enough air or to much fuel. The air filters are clean. Could it be my turbo not working or a bad injector? I really have no clue but an help would be appreciated. TIA Kevin

 

[Tazza]

It could indeed be a turbo issue, that or injectors. You have 70-80 HP with that machine, simply operating your hydraulics, the engine won't know its even there.
Black smoke does mean excessive fuel, or un-burnt fuel. Is there any blue smoke? if there is, it could be your engine oil by-passing the turbo seals.

 

[slewpumper]

It could indeed be a turbo issue, that or injectors. You have 70-80 HP with that machine, simply operating your hydraulics, the engine won't know its even there.
Black smoke does mean excessive fuel, or un-burnt fuel. Is there any blue smoke? if there is, it could be your engine oil by-passing the turbo seals.

The only thing I notice is black smoke. I guess I can take the injectors out and see if they look okay. Not really sure about the turbo and what to look for on that end. Thanks for your input.

 

[mrfixitpaul]

The only thing I notice is black smoke. I guess I can take the injectors out and see if they look okay. Not really sure about the turbo and what to look for on that end. Thanks for your input.

look for carbon build up on the tips of the injectors, alters the spray pattern and makes it smoke/lose power.

 

[slewpumper]

look for carbon build up on the tips of the injectors, alters the spray pattern and makes it smoke/lose power.

Ok thanks for your input. Can I pull the injectors out myself to inspect? I guy at work told me that there is a brass washer that ma need to be replace once I remove them. Is there any special tool that I need? This is a 72hp Duetz diesel. Thanks in advance!

 

[Tazza]

Ok thanks for your input. Can I pull the injectors out myself to inspect? I guy at work told me that there is a brass washer that ma need to be replace once I remove them. Is there any special tool that I need? This is a 72hp Duetz diesel. Thanks in advance!

There should be a copper washer to seal the injector to the head, but i have removed and replaced injectors without doing the washer, they worked just fine.
They should be pretty easy to pull out. I thought they have an arm that holds downwards pressure. Some screw in, i don't know what style yours has, sorry.
It just seems odd that the lack of power just started up. Usually if the carbon buildup slowly happens, the smoke and power loss is also slow to set in.

 

[mrfixitpaul]

There should be a copper washer to seal the injector to the head, but i have removed and replaced injectors without doing the washer, they worked just fine.
They should be pretty easy to pull out. I thought they have an arm that holds downwards pressure. Some screw in, i don't know what style yours has, sorry.
It just seems odd that the lack of power just started up. Usually if the carbon buildup slowly happens, the smoke and power loss is also slow to set in.

Another thought....how many hours....maybe timing belt skipped?

 

[slewpumper]

There should be a copper washer to seal the injector to the head, but i have removed and replaced injectors without doing the washer, they worked just fine.
They should be pretty easy to pull out. I thought they have an arm that holds downwards pressure. Some screw in, i don't know what style yours has, sorry.
It just seems odd that the lack of power just started up. Usually if the carbon buildup slowly happens, the smoke and power loss is also slow to set in.

Actually Tazza it does seem to be getting worse. This winter it only did it a couple times but now it is doing it when ever I dig the bucket into the ground.

 

[slewpumper]

Actually Tazza it does seem to be getting worse. This winter it only did it a couple times but now it is doing it when ever I dig the bucket into the ground.

Well I bought the bobcat a couple years ago. When I bought it I was told it had about 1500 hours on the new Duetz that bobcat put in. I guess the previous owner got a new motor installed by a bobcat dealer because of a spun bearing. I verified with the dealer that this was done. I have put about 500 hours on it since. So I would say around 2000 hours on motor.

 

[Tazza]

Well I bought the bobcat a couple years ago. When I bought it I was told it had about 1500 hours on the new Duetz that bobcat put in. I guess the previous owner got a new motor installed by a bobcat dealer because of a spun bearing. I verified with the dealer that this was done. I have put about 500 hours on it since. So I would say around 2000 hours on motor.

2,000 hours is nothing. You do know the timing belt should be changed every 1,000 hours? if it fails, it will bend your push rods.
Hopefully its just injectors, start with the simple things.

 

[siduramaxde]

2,000 hours is nothing. You do know the timing belt should be changed every 1,000 hours? if it fails, it will bend your push rods.
Hopefully its just injectors, start with the simple things.

Could the hose or pipe that comes off the turbo and goes to the air intake of the engine came loose or got a hole in it?

 

[slewpumper]

Well I bought the bobcat a couple years ago. When I bought it I was told it had about 1500 hours on the new Duetz that bobcat put in. I guess the previous owner got a new motor installed by a bobcat dealer because of a spun bearing. I verified with the dealer that this was done. I have put about 500 hours on it since. So I would say around 2000 hours on motor.

Thanks Tazza.....no I didn't know that.