MEP 007b engine electrical issues

[red]

Helping a friend out with his MEP 007b generator. When you turn the ignition switch on and flip it to start the engine turns over, but no current is being sent to the fuel shut off solenoid, the 2 electrical fuel pumps between the main tank/first 2 filters, or the solenoid that is mounted just after those first 2 filters.

Engine does run when current is applied to the fuel shut off solenoid and the fuel hose is run to a separate fuel can.

 

[Guyfang]

Have you all ever seen this gen set run right? Or did you all just get it from someone else in a non-op condition?

Do you have all the manuals?

Do you have any idiot lights on when you stop turning it over?

 

[red]

He got it in non operating condition.

Will have to check on the lights for what's going on there.

 

[Guyfang]

The two most likely causes of the gen set not starting are:

1. Magnetic Pickup not properly adjusted, the end ground off, missing or is simply defective.
2. Overspeed switch is tripped or defective.

 

[red]

He messaged me today. 2 lights on when the engine is not running. Low oil pressure (usual with any engine) and what he called the 'high rev' light.


Alright so pics for reference. When positive power is applied to the lower terminal on the fuel shutoff solenoid it opens up and the engine starts when pulling fuel directly from a 5 gallon fuel can. Stop applying power to the solenoid by using my little electric probe and the engine shuts off.





Traced the wires back to the box at the top.




Routes in through the large plug at the bottom left corner.




Picture from the opposite side.

 

[Guyfang]

The high rev light means over speed. Press the over speed reset button an see if that doesn't fix the problem. Look in the TM.

 

[red]

Update. Reset the overspeed (which cleared it's light) but there is still no electrical power going to the shutoff solenoid/everything else engine related.

 

[Guyfang]

Have you tested and readjusted the magnetic pickup?

 

[red]

Have you tested and readjusted the magnetic pickup?

Not yet, haven't had a chance to look that procedure over.


Also found a fuel leak at the injection pump, seal around the throttle shaft.

 

[Guyfang]

So how you coming along here?

 

[jmenende]

Have you tested and readjusted the magnetic pickup?

Hi Guy. What voltage am i looking to get at the mag pickup for this 007b? Im looking at the -24p manual but can only find the location diagram.

 

[jmenende]

My unit is reading .115 vac.

 

[Guyfang]

I have to admit, I dont know. But the reinstalling and test set up is in the -34 manual. Something you are not suposed to have. I will also ask a friend who should know.

If you are still having the problem you started with, the S9 and mag pickup are a good place to start.

 

[jmenende]

Did you friend ever get back to you with the correct voltage for the 007b mag pickup?

 

[Guyfang]

He told me that when turning over the engine with the dead crank, you should get 2.5 AC volts. BUT, He also told me to GO BY THE BOOK!! Measure the depth and do it that way.

Sorry I forgot. We are over loaded here.

 

[jmenende]

He told me that when turning over the engine with the dead crank, you should get 2.5 AC volts. BUT, He also told me to GO BY THE BOOK!! Measure the depth and do it that way.

Sorry I forgot. We are over loaded here.

Ok, im going to have to correct your friend here. I have 5 of these units in the lot right now and the newest, an early 90's unit would not start. I suspected the magpickup. Took it off, cleaned the tip and reinstalled it to 9.5vac. Started right up.
How did i get to 9.5vac, well i took the reading off another working unit and that one fluctuated between 9 and 10.5vac. Fluctuations were due to using a set of batteries that were not fully charged. Presto!

 

[SLTRAM98]

Red, (or others)
Did you solve this issue? I have a 007B with 3306 cat doing the exact same thing. Even with Battle short on, the 2 lift pumps do not receive any power. Diodes C27 and C28 were bad, I changed them, still no power to the pumps. Re-set the mag pickup (ran it in until it touched the flywheel, then backed it out 3/4 turns), still no power to the pumps. Engine hits fine if it has fuel, something is not telling the fuel solenoid to open, no ether solenoid action and no pump run. What did you do Red to fix yours? Others welcome to offer input.

Also, was thinking, worst case, I could bypass the day tank and plumb fuel hoses direct to engine fuel system, and hard wire 24v from start switch to the pumps if nothing else works? Prefer to keep it original ofcourse.

Thank you

 

[Guyfang]

IHave you checked the day tank float? When it senses no fuel in the Day tank, it will shut the engine down, and not let it start. It should also tell the fault indicator to show a "No or Low fuel" light.

Do you have the TM's?

 

[Guyfang]

Have you checked the wires to the fuel pumps? They could be getting 24 volts, but if the day tank solenoid will not open, they can not pump. Or if the pumps are gummed up. What you need to do is start a thread, so we can troubleshoot from A to B. Right now, we know diddly squat about what you have done. What it did before.

 

[SLTRAM98]

I do have the TM's, I have read them -12 & -24 (I am still at a loss as to why there is a day tank at all on this genset). I spoke with Cat mechanic shop and they say, bypass the day tank and pump straight to the engine if possible since any excess will bypass internal check and return to the tank. Does anyone know why the military thought a 5 min run time tank on this unit was actually needed?

I have pulled the float out of day tank, checked it over visually, it looks good, I do not know how to verify function though aside from sliding the floats up and down in 'call for fuel' position and it changed nothing.

The low oil pressure dummy light is the only one that stays on; all light up when you hit the test switch as expected.

Genset was running when it quit 11 years ago, then sat in a barn till now.

No voltage at pump wires, already checked. Is there a terminal block that these pump wires run to aside from the CR27/28 TB?

What else do you need to know? I felt like starting a new thread was not useful since this thread is exactly what I am experiencing however I will do whatever is needed.

Thank you