My Challenging MEP-002a's

[storeman]

My Challenging MEP-002a's This is becoming frustrating.

I have 2 of these and one runs well with a livable oil leak (perhaps a quart a day) from the oil housing upper right where a bolt is broken off behind the fan (which I can't get off with a harmonic ballancer puller) got to find or make a heavier puller so i can get at the oil housing.

The other 5kw ran but had a broken glow plug so I swapped the head with a 10kw parts unit I have after asking y'all if that would work. I'm here to report the heads are interchangeable. Well, on removing the head, the center head bolt broke. Have been waiting for a week for a mobile diesel repair guy to drill out the bolt. Yesterday I had a conversation with a millwright friend who suggested heat, break free and a small pipe wrench on the 3/8" tall stud remaining, IT WORKED! The pipe wrench was key. I could not budge the bolt with vise grips or channel locks.

After replacing the head gasket and valve cover gasket and ensuring the IP was working and glow plugs worked and adjusting the valves, I fired her up. She ran and produced electricity but knocked like the devil and produced tons of white smoke. Shut her down and adjusted the valves again. Still heavy white smoke and a little voltage hunting under no load. Removed the air filter....no effect.

The smoke is continuous. Opinions? Recommendations?

 

[JAYHAWK 1962]

If you used new ones, where did you get your valve cover gaskets? i am looking for some spares. thanks

 

[storeman]

from delks military surplus. high price but they had them as well as head gaskets.

 

[Keith_J]

Knocking means timing or delivery quantity is out of specification. It would help to compare the fuel control lever position at governed speed, this is a delicate measurement but you have a good comparison.

It could also be a leaking delivery valve, making injection pressure too low which causes the governor to call for more fuel, increasing the injection duration which makes for white smoke. The delivery valve can be removed without upsetting injection timing. If dirty, it can be lapped. If the center nut on the IP is hot, that heat is from an excessively leaking delivery valve.

This is a modified Bosch system that is far easier to diagnose as timing is fixed (no centrifugal advance) and the governor is external. Just a delivery valve and control collar.

You could also have the injectors pop tested and make sure they hold pressure. If the pop-off pressure is too low, timing will be advanced and it will knock with white smoke.

Lots to check but don't pull the injection pump until all other issues have been checked. If the CARC on the nuts securing the IP to the block is unbroken, timing is probably fine so leave it be.

 

[storeman]

I should have mentioned in my original post that I reused the injectors that had been in the original head
and functioned okay in it. Tomorrow I may try changing out injectors from the 10kw and see if it makes a difference
if no one come up with a solution.
Jerry

 

[storeman]

Keith,
Thanks. I have had these IPs off and apart a couple of times. Never checked the temp of the IP center cap but will do so. I wasn't
sure how the delivery valve played in all this. I wonder if anybody has a spare delivery valve to sell.
Jerry

 

[JAYHAWK 1962]

thanks!

 

[storeman]

Well, changed fuel injectors to the "different but same part number" ones that came off the mep-003a. They look to be in good shape. Unit won't fire and is getting no fuel....so, back to the originals that were on the mep-002a tomorrow.

 

[steelandcanvas]

Hang tough Storeman, we have faith in you!

 

[Keith_J]

Have you checked to see if the injector pump is delivering fuel to the injectors? A sluggish IP will make purging the lines very slow. And if you didn't purge the lines by keeping the fuel line nut at the injector loose while cranking until you see fuel drip, it will take forever to purge the lines.

Professional tip here is to purge the lines with glow plugs removed. Faster cranking and less battery drain. Only do this with the fuel line nuts loose so there isn't any injected quantity. Flooding diesel engines is a bad thing.

Also, make sure the control lever is full up for maximum injected quantity. They have been known to stick in the down position, meaning no fuel injected.

 

[storeman]

All is as you recommended. Changing back to the old injectors today.
Jerry

 

[storeman]

HELP!!!

To update, I took the day off work and spent another day on this generator. It is a unit that ran when I got it but only for short periods of time. All filters, etc replaced. In an attempt to go further, I've pulled the IP several times and timed it several times. Done the valve adjustments, etc. Have found that I had to jump the upper relay to get the glow plugs to function at all. In an attempt to switch glow plugs from the donor 10K, one broke off in the unit I'm working on. Since then have done the following in sequence:

1: Two weeks ago, decided to pull a head from my donor 10kw rather than pay to have the glow plug drilled out.

2 In removing the head to swap with the 10kw, the center bolt broke off just above the block. I finally got the broken bolt out this weekend.

3. In the "new head" I installed 2 of the injectors from the 10K unit but they will not pass fuel, so tried the other two, and niether will they. All looked good but were of a different design than the ones in the 5kw unit. Got nothing but fuel mist/white smoke, no firing despiye jumping the glow plugs. Am wearing out the starter and my battery charger. (3 charging sessions today alone.)

4. Today I pulled the IP and checked timing for the umpteenth time, reset the valves again and reinstalled the original injectors, checked the delivery valve, bled lines numerous times.

5. When I last cranked it, got my first puff of black smoke in 3 days.

6. Am looking for glow plugs. Sources?

7. Comments/recommendations on where to go from here?

Thanks,
Jerry

 

[Keith_J]

Glow plugs are not needed if it is above 50 F. Have you tested compression? Since you have had the cylinder head off, what did the bores look like?

I have noticed a good number of 002A/003As have new engines. These have Onan data plates on them with 1990s contract dates. Just thinking Onan might have had a warranty issue...just thinking though, nothing of substance to prove this. But if your compression is in the 200 PSI or less, starting will be difficult.

 

[RIrvin]

If no fuel to injectors, may wish to verify that your IP is fully and properly bolted to engine block. I had a second O-ring on my pump ( one on pump and one stuck on block) which helped it remain out of tolerance when mounted. Simple error but kept pump from operation.

 

[storeman]

Thanks. Will check further. I don't know what is needed to check compression on these units but I assume the TM will have all. Bores looked okay. I have fuel to the injectors but I may try to get the MEP-003a ones tested. Still need glow plug source. There has to be someone less expensive than Delks.

Anyone know the brand and model number for these glow plugs? Mine just say "made in USA".

 

[storeman]

Found the glow plug info from Home.
Jerry

 

[Keith_J]

Thanks. Will check further. I don't know what is needed to check compression on these units but I assume the TM will have all. Bores looked okay. I have fuel to the injectors but I may try to get the MEP-003a ones tested. Still need glow plug source. There has to be someone less expensive than Delks.

Anyone know the brand and model number for these glow plugs? Mine just say "made in USA".

The $30 Harbor Freight Tools diesel compression test set should have the adapter for testing through the glow plug port. Back when the TM was written, there were very few diesel tooling manufacturers and most compression gauge test sets were for large engines without glow plugs. Hence the use of the injector port.

IIRC, the glow plug threads are 12mm by 1.5 pitch. Always coat threads with anti-seize.

 

[storeman]

the set they offer for diesel is something over $100. the $30 one is generic auto. I ordered a third type kit today from them for about $30 and will advise if it works.
jerry

 

[Keith_J]

You can also make a good guess by hand cranking but always use a ratchet in case the engine fires. It is difficult to crank it by hand with a 10" ratchet at any speed. I listened to mine through the intake (pulled manifold), exhaust and crankcase. The valves were quiet with just a bit of crankcase leakage which is normal.

 

[storeman]

Received my compression tested from harbor fright today. am working all through the weekend but expect to test monday and tues. got the unit running but very rough. Obviously needs a valve cover gasket to replace the one I just replaced and damaged.
jerry