This is a wierd one... this is a Mayco concrete pump with a Deutz 4 cyl diesel. It seems to be misfiring. It's fairly random, and doesn't seem to do it at idle, and seems to start fine. In the video, I'm slowly advancing the throttle to show what it's doing. It only does this a few times in the video, like at :26, :31, :38, :48... The fuel filters are new. I would sure be interested to hear everyone's thoughts on this. Thanks!
It almost sounds like its trying to compensate for load. Like maybe the governor is sticking or hanging up a bit?
I was thinking about that. The engine didn’t actually have a load, but it sure sounded like it. If I understand how the governor works- when you throttle the thing up, if it loads down beyond a certain rpm, the gov tries to open the throttle more to compensate. I could feel the governor trying to open the throttle more when the engine bogged down, so that makes sense. The question is, why did the engine bog down? I’m going to run the compressions tomorrow and see what that shows
Maybe you have a bearing starting to pile up in the unit somewhere... is there a clutch between motor and pump?
No clutch, just a cush drive. The only bearing would be at the input shaft of the hydraulic pump, and when that thing goes, it squeals like a pig, and the pump departs the pattern shortly thereafter. I don't see this as being a compression issue, because it starts so well. I'm thinking t's got to be a fuel delivery problem somewhere. A clogged or malfunctioning injector would usually show itself in other rpm's as well... usually. Maybe it's fuel pressure...
Have you pulled the engine oil filter and cut it open? Might take a sample.
The oil filter? No, I haven't done that. I have to go pick up an ASV, so this this is going on the back burner for today. I left a message with the MFG of the pump. Maybe they'll get back to me someday soon.
Call me crazy but I don't hear a thing??
Crazy! Hah jk. The sound is kinda hard to discern, but you see puffs of black smoke each time as the engine tries to recover. Compressions were all close to 300 - not bad. This engine has individual pumps (I forget what those are called) per injector. I don’t know squat about em.
Individual pumps in a row that all run off the camshaft, with a line to each injector? or unit injectors on the head with no high pressure injection lines? Don't mean much to me, but maybe somebody else. I'm thinking this is a middle aged, over engined, under worked machine? maybe a grout pump or pea gravel pump? I'm thinking it might not get the hours per week that it did when new, and the fuel gets old and sticky. What did the old filters look like? Can you take a peek inside the tank to see if there's any deposits? Maybe drain the tank and see what the intake or drain plug looks like? If those are the injectors I think they are on an old deutz, then it has to have a rack connecting the individual pumps inside of the engine, that could be gunked up, worn, or bent somehow that is messing with the governor movement.
Yeah, I believe they're called motorpal injectors. It's about 10 years old, about 1400 hrs. I don't know how much Deutz derates their engines, but 80 HP is what it cranks out. I'll look into the dirty fuel issue - thanks!
Delmar has a strong point. They have a tin rack that will not tolerate dropping a pump in out of time. It'll bend and not start. Those 4 banger deutz are very resilient. Do you have a glass bowl water separator? Those are prone to failure at the seals.
Just listened to it again. Beneath alternator fan is the fuel shutoff solenoid. 2 wire square screw on plug. Make sure terminals are tight, make sure retaining screw is tight. Follow wires back to square AMP connector block. Make sure continuity is good. That is definitely sounding like the shut off solenoid is cutting out momentarily. Common issue on Miller big blue and volvo compact wheel loaders that both use that engine.
The cutoff solenoid was actually the very first thing I checked, it sure acted like that was the culprit. But - I figured it out yesterday. And the winner is ... (dramatic pause)... Delmer! Yep I got about 25 gallons of crappy fuel. I plumed my fuel can into it for a few minutes, and it ran great almost right off the bat, or as soon as that crappy fuel got through it. I'm draining it... I bet I find an inch of sediment on the bottom of the tank too. Thanks Delmer and the rest of you guys. I appreciate the help!
Just a follow up - there wasn't an inch of sediment in there but it wasn't squeaky clean either. I just rinsed it and dried it and the tank's all clean now. So I told the guy about the fuel and he was all "no way, that's BS". I asked him where he got it, and he told me he got it from one of those tiny discount fuel pumps we have out here. I told him that fuel could have been in those tanks for a year or more and to go to busier fuel stations like truck stops to make sure the fuel is good. I'm billing 6 hours of labor and $150 environmental fee for disposal of 40 gallons of diesel. So, this was a thousand dollar mistake he made. Let this be a lesson to all of us - don't go to those cheapo fuel places!
That's what KILL'S ME about tractor owners.. They'll run the tank dry/run outta fuel & add 5 gallons to a 20-25 gallon tank & then complain or write in on websites asking WHY does my tractor run like crap.!!! & they don't wanna hear ANYTHING about a "tank being dirty".. OR.. "changing filters".. or "try" putting more than 5 gallons in a 25 gallon tank.. I had 1 customer that ran a pump so dry, it actually burned the injector tips from trying to start it w/ no fuel.. it turned the inside of the inj. tips {pintle} BLUE from heat.. Needless to say, the pump was toast too.. I've never in all my years, seen that..