MEP 002A STARTING ISSUE

[Cube]

Have a 002A generator. Sat for a couple of years.
Cleaned fuel tank and pump screens and attempted to start it.
Pumps run and fuel solenoid clicks only.
New batteries so put 24 volts to solenoid start wire and had a big spark at the battery.
Now found out the ground was not connected well. Tightened ground and with battwries connected the starter energizes and turns over.
Note the start switch is not on when this happens.
Did I burn up a diode?

 

[Scoobyshep]

Did it work correctly before being stored?

I know you can get a starter hangup from the voltage regulator. Try this, disconnect the solenoid wire from the starter and see if K3 is being commanded on or if the contacts are in the energized position.

 

[Ray70]

In addition to the above, check the starter itself. I have seen several " old style " starters where the linkage from the solenoid on the starter to the drive gear has gotten frozen. This causes the solenoid to be stuck in the engaged position.
You can quickly verify this by seeing if the solenoid / linkage extends and retracts when you hook up the battery and the starter engages.
If the linkage is not moving, that's probably your issue.
If so, just need to lubricate the pivot pins and possibly take apart, clean and lube.

 

[Chainbreaker]

Yes, there is a Diode CR2 on A-1 Relay Board that could cause this situation (described in PDF attached below). Never heard of it happening from just sitting but who knows...

While you are checking things you should make sure your genset is wired in accordance with the update as was mentioned in PS Magazine article "Starter Burnout" (MEP-002a/-003a) attached below"

 

[Cube]

Scoobyshep, yes it worked perfectly in single and 3 phase
Great thank you for the quick replies.
I'll check the solenoid pivot and the contacts at the K3 contactor.

 

[Guyfang]

 

[Cube]

Scoobyshep, yes it worked perfectly in single and 3 phase
Great thank you for the quick replies.
I'll check the solenoid pivot and the contacts at the K3 contactor.

Scoobyshep, you hit the nail on the head. Yes it was the solenoid pivot point locked up in gear.
Starter could not be removed without removing fan shroud so lubricated it in place. Smooth return spring tension now.
Then did injector pump plunger check, works fine.
Wants to start but injectors are not spraying in diesel.
Going to put seafoam in last fuel filter and turn it over and leave overnight.
Hope it starts, wants to but no fuel.

 

[Guyfang]

Sometimes this gen set is hard to bleed the air out of the system, when it is dry or sucked an air bubble.

 

[Scoobyshep]

Scoobyshep, you hit the nail on the head. Yes it was the solenoid pivot point locked up in gear.
Starter could not be removed without removing fan shroud so lubricated it in place. Smooth return spring tension now.
Then did injector pump plunger check, works fine.
Wants to start but injectors are not spraying in diesel.
Going to put seafoam in last fuel filter and turn it over and leave overnight.
Hope it starts, wants to but no fuel.

That was actually rays suggestion.

Sent from my SM-G973U using Tapatalk

 

[Cube]

Sorry Ray 70 my mistake, thank you for input on starter/solenoid lever.
Ok, turns over now, have fuel to injection pump but not to injectors after many starting attempts.
Solenoid lever is lifting upon start, piston in pump moving freely.
Not sure where to go from here.

 

[Guyfang]

Well, Ray would tell you to start looking at the IP. I will let him tell you what to look at.

 

[Ray70]

You know me all too well Guy!
He is correct:
1) Do you have fuel flow to the inlet of the IP? ( there is a check valve near the oil pressure gage that occasionally gets stuck )
2) If you have confirmed fuel flow to the IP is good, crack open one or both injector lines and see if you are getting any fuel pulses out of the pump.
3) If no fuel out of the pump remove the center cap on the IP, then remove the inner 5/8" 12 point cap and the delivery valve holder. You will now be looking at the plunger in the center of the IP. Rotate the engine by hand using a 5/8" socket on the blower wheel bolt. Look very closely at the plunger in the center of the pump. It should be rotating at 1/2 the rate you are turning the motor by hand and at the same time it should move in and out about 1/4" once every revolution of the crank.
4) if the plunger is not moving in and out and spinning, look at the pump body and tell me if it has a large flat head screw sticking out of the boss on the underside.


5) if there is no screw and your pump looks like the one on the right, go grab a 12 pack of beer and celebrate, you have an Ambac M50 pump that can usually be rebuilt. If it has a screw like the pump on the left, go buy a 12 pack of beer and start drinking heavily before I give you the bad news that your Bosch PSU pump probably has a broken plunger which can not be repaired. ( but I won't say anything until you confirm all 5 above )

 

[Cube]

You know me all too well Guy!
He is correct:
1) Do you have fuel flow to the inlet of the IP? ( there is a check valve near the oil pressure gage that occasionally gets stuck )
2) If you have confirmed fuel flow to the IP is good, crack open one or both injector lines and see if you are getting any fuel pulses out of the pump.
3) If no fuel out of the pump remove the center cap on the IP, then remove the inner 5/8" 12 point cap and the delivery valve holder. You will now be looking at the plunger in the center of the IP. Rotate the engine by hand using a 5/8" socket on the blower wheel bolt. Look very closely at the plunger in the center of the pump. It should be rotating at 1/2 the rate you are turning the motor by hand and at the same time it should move in and out about 1/4" once every revolution of the crank.
4) if the plunger is not moving in and out and spinning, look at the pump body and tell me if it has a large flat head screw sticking out of the boss on the underside.
View attachment 831330

5) if there is no screw and your pump looks like the one on the right, go grab a 12 pack of beer and celebrate, you have an Ambac M50 pump that can usually be rebuilt. If it has a screw like the pump on the left, go buy a 12 pack of beer and start drinking heavily before I give you the bad news that your Bosch PSU pump probably has a broken plunger which can not be repaired. ( but I won't say anything until you confirm all 5 above )

#1 yes fuel to pump.
#2 yes some fuel comes out of pump with lines removed.
#3 piston turning and moving in and out.
#4 pump has a screwy under it so guess its a Bosch PSU pump.

 

[Ray70]

Sounds like your IP is most likely OK.
I would reattach the lines at the pump and just crack them open a 1/2 turn at the injectors and verify that you get a very small spurt of high pressure fuel up at the injectors. NOTE: is will be just a small amount of fuel every other revolution of the engine.
Try to verify the the flare fitting on the end of the line is loose and not stuck tight in the injector or you may get a false negative on the fuel flow.

When you removed the lines from the pump, the fuel you saw could just be from the electric fuel pumps if it was a small stream each time.

If you get fuel at the injectors but you are not seeing any smoke at all while cranking and attempting to start then I would start looking at the injectors.

If you do not get pressurized fuel at the injectors you may have something going on with the delivery valve or other issue with the IP.

You can remove the injectors and see if the tips look wet or if they appear completely dry.
You could also remove an injector and reattach to the line and crank to motor to see if it is spraying BUT, you have to cap the 1/4" return line that screws into the injector or you will have fuel from the electric pumps flowing out of it.

 

[Cube]

Sounds like your IP is most likely OK.
I would reattach the lines at the pump and just crack them open a 1/2 turn at the injectors and verify that you get a very small spurt of high pressure fuel up at the injectors. NOTE: is will be just a small amount of fuel every other revolution of the engine.
Try to verify the the flare fitting on the end of the line is loose and not stuck tight in the injector or you may get a false negative on the fuel flow.

When you removed the lines from the pump, the fuel you saw could just be from the electric fuel pumps if it was a small stream each time.

If you get fuel at the injectors but you are not seeing any smoke at all while cranking and attempting to start then I would start looking at the injectors.

If you do not get pressurized fuel at the injectors you may have something going on with the delivery valve or other issue with the IP.

You can remove the injectors and see if the tips look wet or if they appear completely dry.
You could also remove an injector and reattach to the line and crank to motor to see if it is spraying BUT, you have to cap the 1/4" return line that screws into the injector or you will have fuel from the electric pumps flowing out of it.

Ray,
I removed the 1" cap and checked the piston Wednesday. When reassembling I put a little red grease on the delivery valve assy as it kept falling out of the piston hole and put spring back in 5/8" cap and tightened it.
Upon opening it today the spring is bent at one end.
Straightened it and need a better method of reassembling it. Since it is on the side of the motor gravity pulls the parts down on reassembly.
Any suggestions?

 

[Ray70]

Ok, the reason you're having difficulty is that your delivery valve spacer is deteriorated an / or missing ( #5 in the image )
It's a paper thin plastic ring that goes around the delivery valve holder to keep it in place while you reassemble it.
They tend to fall apart over time.
You could buy a replacement from Ambac PN SR-8515, but they are about $28 and Ambac has recently stopped selling direct to the public, unless you are an existing customer.
The grease trick is the common method, but I actually usually get it in place with nothing, just a fast hand I guess.
I usually put the valve into the IP, let it droop down, then put the spring into the cap and screw the cap on, but a little grease on both the valve holder and grease in the cap to hold the spring too may help.
How badly did the spring get distorted?

 

[Ray70]

Also, while you're in there, double check that there aren't any remaining little pieces of the spacer stuck to the #4 holder or down in the body where the tapered edge of the holder seals. Any little chunks stuck in there will prevent the pump from building pressure.
It would look like a very thin sliver of crap, usually black or very dark brown after sitting in diesel for 30+ years.

 

[Guyfang]

When you took it apart, you may have dropped it. So look around. If you find pieces in the IP, you might want to consider taking the IP apart, and cleaning the whole thing.

 

[Cube]

I straightened the spring. I see the spacer it is brown but still in the recess in the pump. Used grease and reassembled it.
Now have fuel to injectors and tries to start and some smoke but wont just kick to start. Very fast turn over some smoke then no smoke and slowed down a little.
Let it sit 30 min and it has smoke and fast turn over then slows down.
Must not be getting enough fuel or fuel pressure to the injectors.
I'll have to see if I can get the new spacer and a new spring?

 

[Ray70]

Before you do anything else to the pump, make sure your batteries are in good shape, it sounds like they may be wearing down as you are cranking.
Next, are you using the glow plugs? If so how long?
You might need them for 30 seconds min.
If that doesn't help we may need to verify the glow plugs are working.
Also, make sure that while cranking the IP throttle linkage is lifting fully upward and not binding up on the sheet metal or anything. Have someone push up on the linkage with a finger while you are cranking to verify it is fully upward.