Bobcat 863, Deutz 1011F, need help with diagnosis

[obleck]

Hello all,

I acquired this machine a few month back and have more or less fixed a variety of issues, including overheating and fuel/oil leaks.

Today I bolted the muffler back on top of the engine, and after some manual fuel pumping and jump starting, got her running again. She'd been sitting probably 2 months. I was surprised the fuel had drained out of the system, but she didn't fire at least until I pumped and bled a bit.

So I ran the machine pretty hard for a while, 10-15 minutes say, and then shut her down. When I started it again, it ran for maybe a minute and then completely started coughing and running really rough, plumes of intermittent white and gray exhaust, no power, just BAD. Eventually quit. Oh oh. I fired it up again, which it did okay, but the symptoms persisted. Except there would be intermittent moments where it seemed to run okay for a few seconds. I did this probably 20-30 times to limp back to my repair area in the intervals when it ran a little smoother. Strangely enough, it sort of helped a little to have a load on the engine.

So what could be wrong here? I will say that there was a definite ticking before, which I can't identify necessarily as having been a valve.

I also don't understand how the fuel metering and injection quite works in the Deutz. It has this "distributed" injector pump at each cylinder, and I don't know off hand how the fuel metering or governing works. Hence why I'm asking here.

Possible problems:

1) Easy answer: lots of water in the fuel? I'll do some draining. Fingers crossed it's that simple...

2) Something wrong with the injector pump system? Why would it be intermittent?

3) Valve issue?

4) Blown head gasket? But again, why intermittent performance? The machine also isn't overheating, runs around 215-235 depending on the load, which seems to be right for this Deutz.

Any suggestions appreciated.

 

[willie59]

A faulty head gasket on a 1011 or 2011 will typically produce some smoke when running, and when it gets bad enough it will put oil droplets on a white paper towel held in the exhaust stream, but they'll still typically run decent in that condition. Intermittent missing, running rough and puffing smoke is typically fuel supply is not quite there, enough there to make it run but other times just shy of enough fuel and you'll get those rough running spells. Check your fuel supply system all the way back to the tank and lift pump as well. BTW, if you don't know the maintenance history of that engine I'd suggest replacing the timing belt and tensioner before they become a problem.

 

[thepumpguysc]

Heed the warning on the timing belt.. special tools (timing pins) are required & can be bought as a kit ..
Pins, instructions, belt and tensioner..
Your spitting and sputtering sounds like a lift/supply pump problem..
I think u can take the cover off the supply pump and check the filter and valve condition..
Bad valves in the sp can allow fuel to back flow to the tank..
BUT.. check to make sure u have good fuel AT the sp & not a trickle.
Good luck.

 

[obleck]

Hey guys, thanks for the suggestions. I do know from the guy I bought it from that the most recent timing belt is in fact recent/low hours. I have no reason to doubt it.

After sitting for more than a few days, the lift/supply pump does seem to lose fuel, so apparently the check valve in there seems to be bad. Good to know. (If less than a few days, everything seems to start just fine). Do you know offhand if there is a rebuild kit for those? Or is it easier/as cost effective to just put in a new pump?

Fuel seemed to be fine at the supply pump and at the injector pump inlet for that matter when I was bleeding the system prior to the incident. I'm leaning toward a LOT of water, though perhaps it's the pump itself.

I'll check the pump and water separator tomorrow.

 

[obleck]

Update:

So the machine did sit for 2-3 days since I last started it, and the fuel had again drained out of the lift pump.

I also took the cover off the lift pump, and as it turns out there is a strainer in there, and it was quite clogged with grit, seemed like rust of sorts, probably from an old water separator filter. I cleaned it, drained the water separator, re-primed everything, and it started up okay, though smoky until it warmed up. I presume it overheated a bit too much some time ago and the valve seals and rings are not what they could be. It cleared up fairly well once it got warmed up though.

Anyway, Whew, nothing outrageously problematic. I need to replace whatever check valve is in the lift pump. Looking for a kit.

Anybody got a favorite additive or something to improve the smokiness?

It's also leaking a little oil from the TOP of the valve cover. It seems to be bubbling up slightly from under a placard, maybe a rivet in there or something? I replaced the valve cover pressure relief valve and the muffler insulation, since the valve had actually melted and the insulation was clogged with oil and soot. Any ideas on that?

Lastly, I need to get the glow plugs working--I don't think they are. Sometimes when I turn the key, I have to wait a few seconds until it fires. Is this normal? i.e. is there a glow plug preheat timer that delays the solenoid on "Start"? Or is the solenoid being sticky?

 

[willie59]

Don't tinker with the lift pump, just replace it and save you worries, all things wear out, just replace it and move on. And I could be wrong, but I don't think the Deutz engines have glow plugs.