bobcat 873 big problem?

[90plow]

I started the 02 bobcat the other day and ran it for a little while to keep the batteries charged. I parked it after about 45 minutes and went to start it again today. I waited for the 20 sec. glow plugs to turn off and it sounded like it was dieseling when the motor first started so I gave it about 1/8 throttle. The machine sat for about 10 minutes warming up and I tried to throttle up but it sounded like an old detriot motor and was smoking like a bandit. I have been having problems with this machine on and off and was thinking it might have been the fuel filter but this sounds like it might be the turbo?!?!? Called the dealer and they said the bearing might have gone and the turbo would be shot. Anyone have any similar experiences. The machine is a 2002 bobcat 873 with about 1700 hours on it.
Thanks in advance
Eric

 

[John DiMartino]

Id be looking for more than an over the phone diagnosis. First off,was itcold enough to gell? If its possible,treat the fuel with powerservice,and try again. What color smoke are you getting,Is the oil level low? if the turbo bearings are failing,hope its on the exhaust side,where it just makes smoke,an intake side oil leak leads to a runaway diesel. You cant even get it to rev up,even if the bearings are going,it still should be able to rev up without a load on it.Get a local on site diesel repair service to look at it,or get it to the dealer before you do more damage to it.

 

[bobcatmechanic]

there is a black cover on the l/s and r/s of the machine 2 1/2 bolts wrench size pull them out leave the 9/16 wrench size in there swing the cover out of the way pull the air cleaner box off 2 hose clamps and 2 9/16 wrench size bolts out of the air filter box side and pull it off reach in and grab the turbo impellar shaft and go left to right up and down and in and out there should be little to no play also look at the fins on the impellar and see if they are all bent up and shot i have seen turbos go out on those deutz before not to many but 2 or 3 in the 3 years i have been working on them

 

[willie59]

Your dealer either didn't want to take the time to mess with you, or they are trying to hustle business, or they don't know what the heck they're talking about! First of all, it ain't your turbo. On any diesel engine, the turbocharger doesn't even become a factor until the engine hits somewhere around 16 - 1,800 rpms, and even then, under load. At engine idle, or even high idle, the turbo isn't doing anything, might as well still be in bed asleep. Remember this, for a diesel engine to run it requires three things; 1) air to ignite fuel. I doubt you have a problem with air because you had previously run engine with no problem. Again, the turbo has nothing to do with aspiration, only producing more air for combustion under load. 2) compression of air. Again, I don't see where you have a problem with compression from an engine that ran fine previously. That leaves 3) fuel for the fire. That's the final component needed to make a diesel run, and the most likely culprit of your problem, not the turbo.

 

[BAREIN]

Hard to diagnose off what you said but, it Could be your head gasket, which the duets is known for, be careful running it because if it gets to bad you have to figure out a way to shut it down because the engine keeps running off the oil. I had A 97 and the gasket went bad at 900 Hours. If your mechanical fix it yourself, its pretty easy, when My dealer gave me A price it was over a grand, I did mine in under a day.

 

[bobcatmechanic]

you may check your fuel pressure out of the pump it should be about 5-7 psi you can also take the pump apart and check the screen in the pump just take the phillilps screw out and seperate if it is the head gasket and you can get it done in a day if you are mechanical

 

[90plow]

Thanks for the help guys Ive been real busy lately and havent had time to get into it. I just bought some diesel 911 and im going to add that and see what itll do. If anything is wrong Ill be fixing it myself. My grandfather is a heavy equip mech so he can help if need be. Ill be getting into it after this snow storm we have coming and Ill keep you posted thanks again.
-Eric

 

[special tool]

there is a black cover on the l/s and r/s of the machine 2 1/2 bolts wrench size pull them out leave the 9/16 wrench size in there swing the cover out of the way pull the air cleaner box off 2 hose clamps and 2 9/16 wrench size bolts out of the air filter box side and pull it off reach in and grab the turbo impellar shaft and go left to right up and down and in and out there should be little to no play also look at the fins on the impellar and see if they are all bent up and shot i have seen turbos go out on those deutz before not to many but 2 or 3 in the 3 years i have been working on them

This is good advise, but let's remember that there will be wiggle room in a plain bearing turbocharger when the engine is shut off and there is zero oil pressure.
This is because there is a few thou of clearance in the bearings that gets occupied by oil when it is running.
A lot of turbochargers are mis-diagnosed as bad because of this.
The newer ball-bearing turbos should not wiggle when you perform this test, however.:drinkup

 

[special tool]

Oh yeah - almost forgot.
Its not the turbo.

If you are letting it sit long enough to worry about the battery, that means you probably just have some moisture in the tank which froze.

 

[90plow]

I would agree but ussually frozen fuel doesnt lead to tons of smoke coming out of the machine. I brought it in the garage tonight to see if itll defrost and run right. Ill keep you posted.

 

[Alan Mesmer]

Sounds a little like what just happened to my older New Holland L785 skid steer. I do not use it very much at all and especially this time of year and it is stored outside so I also start it every week or so and let it run to charge the battery and get the fluids moving.
Well the last time I waited for the temps to hit the 30's and started it and ran it at about a 1/4 throttle for 20 minutes. That's about when things got interesting - I took it up to 1/2 throttle and noticed that I had excessive blue smoke and loss of power. Thought it may somehow be fuel; checked and changed filter, water trap, etc. but it did not help at all. Changed air filter also but same thing - blue smoke/no power. I took it to my mechanic and on teardown he found a very stuck intake valve and bent rod. This was surprising as this machine has very few hours on it (1700) and has been maintained very well with the oil being changed always on schedule. Letting things sit outside and not running them is just not good.
Good luck with your issue.
Alan

 

[90plow]

Well to all of you that doubted it being a turbo issue you were correct. The mechanic broke it down and the turbo was fine but the timing belt skipped a tooth not good. Hopefully the carnage inside the motor as far as the rods and valves go isnt too bad.

 

[bobcatmechanic]

at most its 8 new push rods and run the over head a timing belt and your good to go

 

[John DiMartino]

Well to all of you that doubted it being a turbo issue you were correct. The mechanic broke it down and the turbo was fine but the timing belt skipped a tooth not good. Hopefully the carnage inside the motor as far as the rods and valves go isnt too bad.

To me,the fact that an industrial use diesel uses a timing belt is troubling.I though all real diesels used a gear drive or a timing chain at the worst case. I thought timing belts were used small,high rpm light car engines. I know the little VW diesels have them,but they are car engines...
At least you know the problem now,and you can keep better track of the timing belt,they must have a service life in hours.

 

[bobcatmechanic]

every 3 years or 3000 hrs which ever comes first or it breaks in that case that came first and someone didn't know the service time to change it its actually pretty cheap and quick to do about an hour is all it takes to change in actual work now what they charge you is a diffrent story

 

[90plow]

The machine doesnt even have 2000 hours on it right now. The mechanic went over the motor pretty thoroughly before finding it was the timing belt. In retrospect it may have been cheaper going to bobcat but they moved about an hour away so its a pita to bring it out there. All the rods were bent and one was acctually broken parts are ordered lets hope the valves themselves arent bent. Im thinking this machine isnt as bullet proof as I was led to believe.
-Eric

 

[John DiMartino]

The machine doesnt even have 2000 hours on it right now. The mechanic went over the motor pretty thoroughly before finding it was the timing belt. In retrospect it may have been cheaper going to bobcat but they moved about an hour away so its a pita to bring it out there. All the rods were bent and one was acctually broken parts are ordered lets hope the valves themselves arent bent. Im thinking this machine isnt as bullet proof as I was led to believe.
-Eric

Problem with rubber belts is not so much the 2000hrs,but time and heat.Thats why they recommend every 3 yrs to replace it.If the machine is over 5 yrs old,they break down quickly and develope cracks on the corners of the belt lugs.The heat from being right up against the engine coupled with time.Eventually the teeth will weaken,and right aftera cold start,with thick oil,and more drag is when they usually let go.Thats why I hate timing belts,they do not belong on heavy equipment.

 

[90plow]

How true John. Well the mechanic fixed the rods none of the valves appear to be bent when he ran it he said. Total bill was $900. I thought in the begining he was saying it was going to be $900 to diagnose it just a little miscommunication. I think we got away relatively easy considering what could have been.
-Eric

 

[John DiMartino]

How true John. Well the mechanic fixed the rods none of the valves appear to be bent when he ran it he said. Total bill was $900. I thought in the begining he was saying it was going to be $900 to diagnose it just a little miscommunication. I think we got away relatively easy considering what could have been.
-Eric

Erie,It could have been a lot worse than $900. All things considered,you did ok.Thats one thing that scares me with my Cat 246,if I ever lost the motor,with the current the prices of a quality reman small diesel engine,whether it be Kubota,Perkins,John Deere,Cummins,Deutz,and Yanmar is downright scarey.For an older machine it may be a deal breaker on repairing it,forcing you to sell it with a bad engine(worthless) or wait it out looking for a used one,which is hard to find.At least you now know to have the belt done in 3 yrs if you still have the machine,it wont cost 1/2 as much,and you'll avoid playing russian roulette with your $ engine.

 

[90plow]

Well the machine starts and runs better than it did before. The mechanic said the maintenance schedule has the timing belt replacement at every 800 hours just figured Id pass that on to you guys.