MEP002 running for only 45 seconds at a time???

[1800 Diesel]

Ok, I ended up making a more permanent new tank for it, checked all the connections, flushed the fuel and added some Diesel Kleen, and re-bled it. Oil was good but it is on the front of a M103 trailer and the low oil cutoff is rotated higher than usual when attached to my truck so I jacked it up to make sure it was fully level. Took about 5 attempts but engine finally fired off. At first wouldn't get about 38hz and was vibrating very badly. If I had to wager a guess, I would suspect it is operating on one cylinder. The engine would sound like it is screaming but it wasn't even at 60 hz yet. After a few seconds, it would take full throttle to run at 60hz. Oil pressure is good. After a few more seconds it sounds like the other cylinder kicks off and the smoke goes away and she smoothes up but I have to immediately push in the throttle as the RPM's start to surge. As it starts to die, I life up on the Engine Stop Solenoid (Pg 3-25 of the operator tech manual-Is this the correct switch you guys wanted me to lift up on?) and she would keep running but she would rev up substantially. As she starts to die, the whitish smoke (could have a darker tint to it as well) comes but goes away when she comes back to life. The smoke does seem to smell burned. At the end, lifting up on the solenoid, the engine kept running at about 1200 RPM. I took my finger away and she kept chugging at that RPM as I went to kill it. Seems like fuel delivery to me. What do you guys think?

Mental note to myself NEVER to do again, I originally zip tied that switch for some stupid reason (so I could look at the control center and adjust the throttle) and when she fired off, I couldn't get her to shutdown, not even with the circuit breaker (makes sense).

Andrew--I've had to remove the stop solenoid, take them apart (pretty simple) and clean the inside bore and other parts, then lube with light oil and work it up and down several times. Prior to installation, remove the oil and just add a little liquid wrench or similar. Don't use too much as it will attract dirt and stick more. You can also reassemble the solenoid but don't install it and then hook up 24 volt circuit so you can work it electrically to see how it behaves.

The concern I have is the individual cylinder nor firing--I don't believe one cylinder would not fire due to a solenoid problem--if you're getting good fuel to one cylinder but not the other, then it seems more like an injector clog or something else with the injector.

 

[Speddmon]

Sounds like you have a couple of things going on here. I think your solenoid is fine. It does sound like you have a non firing cylinder, and once it gets some heat on it it wants to run...for a bit. You'll need to do a compression test to find out if it truly does have low compression, but I suspect you'll find it does.

It could be the fact that it is running so slowly and your oil pressure is not up to the point it should be that was causing your solenoid to want to drop out. But something was definitely telling it to drop out, and when you held it up, it kept running. To find out which it is (it can really only be 2 things once you have it running), start by putting the two wires of the oil pressure switch under the same screw and run it again, this bypasses the oil pressure switch. MAKE SURE YOU HAVE GOOD OIL PRESSURE WHILE YOU DO THIS, AS YOU WILL HAVE NO SAFETY WITH THE SWITCH BYPASSED LIKE THIS. If it stays running by itself this time, then you have it narrowed down to either the low RPM oil pressure, or a flaky switch. If it still wants to not stay running, then next you'll want to put the oil pressure switch back to normal. And take the small connector off of the air shutter box right above the battery box toward the control box. Once removed, place a small wire in the two sockets that are being used...this is for the high temp shutdown switch. What you are doing is jumpering out that switch and bypassing it. If the set wants to stay running now, then you have a bad thermal switch.

 

[AndrewOH]

Thank you gentlemen for the helpful responses. I would like to verify a few things with you guys to make sure I fully understand the system. I ran my other 002 last night to see how the fuel cutoff solenoid operates. Fully down and it shuts off the pump, fully up is wide open throttle. It seems to normally operate in the middle. So when I hold it up, I am really holding it in the middle so it just doesn't go fully down, is that right?



When I have been starting it, because of the low RPM, I worry about the voltage regulator: would turning the voltage down all the way help even a little in protecting this circuitry?


My not running so well generator seems to sometimes chug along in idle and there is a definite puffing of white smoke from the exhaust. At 1200 RPM's, if only one cylinder was firing, it would be about 2.5 puffs per second which, from a WAG, it appears to be so lending more credit to only one cylinder firing.

How does low compression play into a cylinder that occasionally fires up? To check compression, does anyone make a fitting that you know of to bolt in place of the injector to check it?



Would it be worth it to take off both fuel lines and crank the engine to flush the fuel lines? My thought would be to use a small impact wrench to turn the engine instead of using the starter. If I were to hold up on the cut-off solenoid with the fuel pumps on, I think this may work or completely solve my problem by rendering the engine useless...



I will also start checking the other pieces of the puzzle one at a time. I'll also check the glow plugs in the head while I am at it.

Thank you again for all the help so far!

 

[gimpyrobb]

I wouldn't use an impact to try and start it. The bolt will shear.

 

[Triple Jim]

An 002A/003A regulator won't be hurt by running the engine below 1800 rpm. The regulator works the opposite of what you might think, by supplying current to reduce the generator output, so when running slowly it's working the least hard. Not that these regulators don't fail, just that they don't fail because of running below 1800 rpm.

 

[Speddmon]

Thank you gentlemen for the helpful responses. I would like to verify a few things with you guys to make sure I fully understand the system. I ran my other 002 last night to see how the fuel cutoff solenoid operates. Fully down and it shuts off the pump, fully up is wide open throttle. It seems to normally operate in the middle. So when I hold it up, I am really holding it in the middle so it just doesn't go fully down, is that right?

The solenoid has nothing to do with throttle or engine speed. It simply pulls up the stopper rod on the IP so you can get fuel to flow to the cylinders. If it does not stay up, you cannot start the set. There is no half way, it is either up or not.

When I have been starting it, because of the low RPM, I worry about the voltage regulator: would turning the voltage down all the way help even a little in protecting this circuitry?


My not running so well generator seems to sometimes chug along in idle and there is a definite puffing of white smoke from the exhaust. At 1200 RPM's, if only one cylinder was firing, it would be about 2.5 puffs per second which, from a WAG, it appears to be so lending more credit to only one cylinder firing.

How does low compression play into a cylinder that occasionally fires up? To check compression, does anyone make a fitting that you know of to bolt in place of the injector to check it?

Diesel engines need 3 things to fire off...Fuel, Air and Heat. Fuel and air are pretty self explanatory. The heat is generated via compression in the cylinder, low compression, not enough heat. After it runs and fires off for a little bit, the metal parts expand slightly and seal things up a little better and she'll possibly start to fire or sputter a little. As for the compression tester, search here on the site, another member made an adapter you can thread into the glow plug hole and adapt a compression tester to it. Search for userID luckydog, I think he was involved with the part, either testing a prototype or posting dimensions for the build.

Would it be worth it to take off both fuel lines and crank the engine to flush the fuel lines? My thought would be to use a small impact wrench to turn the engine instead of using the starter. If I were to hold up on the cut-off solenoid with the fuel pumps on, I think this may work or completely solve my problem by rendering the engine useless...



I will also start checking the other pieces of the puzzle one at a time. I'll also check the glow plugs in the head while I am at it.

Thank you again for all the help so far!

Not really worth while....you are already getting fuel or you wouldn't get any firing of the cylinders or smoke.

 

[AndrewOH]

I haven't gotten a compression check done yet however I feel you guys are dead on about the low compression. I pulled the glow plug out of what I suspect is #2 and it was badly corroded although #1's looked brand new. I decided to check the valve adjustment before checking the electrics and stopped dead in my tracks on what I found. I spun the engine several times and came to the conclusion that #1 cylinder is closest to the generator head (at least I think so). Following the TM, I got .012 for the exhaust and I couldn't even measure the intake because it was so loose as my feelers only went up to .025. Continuing with the TM's adjustment for #2, the exhaust was ok, however the intake had 0 clearance and was very tight. Do I have the valve's order screwed up? I haven't adjusted anything yet as it is 85 degrees at midnight in Ohio right now and I am afraid I have them backwards. Although, even with switching the order of A and B, the valves didn't make sense...Thanks!

 

[Munchies]

Did you follow the directions on valve adjustment where you must align the "A" and "B" marks on the generator side flywheel in the sight hole?

 

[dangier]

#2 cylinder is closest to the generator head. Are you rotating the engine in the right direction when checking valve action? Facing the engine fan, the correct rotation is clockwise. You want to check the clearances on the compression stroke. The flywheel has three marks that you will get familiar with real soon. They are the "A" and "B" as mentioned above and "PC" that you will need to check the timing. If your flywheel is rusty, they may be hard to find, but they are there.

 

[AndrewOH]

Yes, I found the markings. The "A" was very hard to find and I passed it quite a few times before realizing it. I've been spinning it clockwise as well. So, #2 is closest to the genny head-I had that backwards, thanks! I will recheck them this weekend.

 

[dangier]

You may have to do the adjustments and then turn over a few times and recheck your settings. Pretty easy to get a little off. At least it was for me anyways.

 

[AndrewOH]

Hey guys,

I must apologize, I made two mistakes initially troubleshooting the problems. I worked some more on it this weekend: adjusted the valves (not too far off from tolerances) and installed a fuel pressure gauge. I also played with the cut-off solenoid. I realized that the solenoid is not actually connected to the injector pump but just pushes down on the linkage. Therefore, I had not been holding it up but instead was holding up on the throttle (mistake #1) Started it today and luckily I had a cloudy white background to really watch the smoke. The smoke is definitely blue (mistake #2). The cut-off solenoid never drops out, even when the engine is only idling. It actually stays in for about 2 seconds after I shut it off, then it drops out. She ran fine again for 45 seconds with just a hint of blue smoke, then one cylinder drops out and tons of blue smoke pours out. If I am quick enough, I can blip the throttle and the clock begins again for about another 45 seconds before she goes through the exact same process. I had her running for about 3 minutes doing this. Fuel and oil pressure remain steady the whole time. Even when she drops down to an idle on one cylinder, she will continue to run for as long as I want idling until I turn her off. Sorry about the wrong rabbit hole initially...

 

[Munchies]

When you say idling, do you mean 1800rpm or with the throttle all the way relaxed?

 

[AndrewOH]

When you say idling, do you mean 1800rpm or with the throttle all the way relaxed?

. I refer to it idling when one cylinder cuts out: the unit, even with wide open throttle when on one cylinder, she only runs between 1000-1200 RPM.

 

[Munchies]

Funky...
it's either fuel or compression related. I would start with the easiest first and move to the hardest. R&R injectors. Remove them have them pop tested and the spray looked at. Adjust for pop or replace nozzles if the spray looks like crap.
After that, if you have no improvement, pull the pump, disassemble, clean everything, inspect everything and put it back together with fresh gaskets and o-rings. Where were you checking fuel pressure at? Might want to inspect the check valve right before the injection pump as well

 

[Jimc]

just a little fyi. i have sent every injector for all 4 generators out to storeman/jerry to have him test and tune them. a total of 12 injectors. out of those 12 there wasnt a single one that was right. those things just get sticky and pop too high or after 30 years the spring weakens up and they are low psi and out of spec. i would start there if i were you and even if thats not the cause atleast they will be tuned up and in spec so when you do get her running it will be smooth and trouble free. pull em out and ship them off to storeman. he is quite reasonable for this service and does a fantastic job with quick turnaround.

 

[storeman]

Jimc, thanks for the endorsement. I agree with you and Munchies on the injectors likely being the problem. Sounds as though one injector is popping at a very low pressure.

BTW, your new nozzles are due in today.

Jerry

 

[Jimc]

Thanks jerry