New Member/Western North Carolina RE: MEP 003A

[dangier]

Bill,
Some of your postings sound like the issues I had with my 002. I went the ether route when my unit would start and then not start. Believe I damaged both pistons with the ether (had to replace them). I thought I had a compression issue when thinking back the ip fuel shutoff might have been sticking on the sheet metal housing then opening up with the engine vibration shook it loose using the ether. Have you watched the ip throttle arm open up when someone else cranking? Apologize if this has already been covered already, but I have experienced the frustration too when the unit starts and then will not start. Sounds like everything else has been covered.

These are really rugged units (when one has confidence that will start when needed).

Hang in there,

David

 

[steelypip]

First, if you want starting fluid, use something safer than ether - it's not kind to these engines. Used to be WD-40 was a good choice, but I don't know what works well these days.

Second, if you can't get a diesel to start and you know the glow plugs are getting hot, then your problems are either compression, cranking speed, or fueling.

Compression, though, can be tricky - bad valve adjustment can cause low cranking compression, too. On a low RPM engine like this, lack of runtime can result in one or more rusty valves or valve seats - a self resolving problem if you just run the engine under heavy load for a few hours. That might help with ring seating as well.

Go look on the web for a few videos of MEP-002As and 003As starting. That'll give you an idea of what a normal cranking speed is. If yours is slower, it's starter rebuild time. For that matter, I'd probably pop the starter off and have a look anyway - I've never had one on anything that didn't crank the engine better after cleaning the commutator and applying a little grease in the right places even if it was 'OK' before.

You checked the glow plugs, but did you check the circuit that powers them? Mine barely starts below about 70 degrees F without some glow plug assistance. I've never checked to see what the minimum no-glow-plug starting temperature is, but it's not very low.

That leaves fueling. I'd probably see if an injector can be removed and hooked up to a line to verify that the inj pump is actually doing what it's supposed to do.

 

[ZeusDiesel]

Thanks, Jerry: I will go with the easy one first and check the glow plugs for veracity. That might explain how this whole thing started in the first place, with it just suddenly not starting: electrical issue. I'll see if I can find info on the specific kind of test I need to do.... Feel good about the batteries and starter. It was turning like a champ yesterday afternoon after it charged them while running.

Bill

 

[storeman]

Bill,
If I recall correctly, your glow plugs should test 0.6 ohms from top to tip. If they read open, they are shot. All 4 must be 24 volt units. If you have an infrared temp sensor gun, the plugs should be up around 150 degrees after a minute of preheat. If no gun, use bare hand and each plug should be too hot to touch.
Jerry

 

[Triple Jim]

Do you mean 0.6 ohms when all four glow plugs and the two intake heaters are connected? I can't find the spec at the moment, but individually they have to be higher than that.

 

[storeman]

Jim,
I may be recalling incorrectly but that is the measurement with plug uninstalled and on the bench, I believe it is either 0.6 or 6 ohms. Don't have the TM handy.
Jerry

 

[Jimc]

if that spec is correct and it does sound familiar to me it would be 6ohms not .6

i can throw a meter on a good one since i have a stock of new champions sitting here.

 

[Isaac-1]

I just tested all of mine individually last weekend, pulling the blade connector off each and testing to the frame, all measured just over 6 ohms (6.1-6.4)

Ike

p.s. mine were all wired with Y splice blade fittings between the wires and the glow plugs, I don't know if this is normal, but one Y's was mis plugged having the connection wedged between the plastic heat shrink and the connector, fixing it did not improve my marginal cold starting issues. I am now thinking I have an injector and or weak starter problem

 

[Triple Jim]

Ok thanks Jerry, Jim, and Ike. 6 ohms would be about 4 amps each at 24 volts, which make sense. I measured all mine, but it's been a year, so all I remember is that the total current draw was like 20 or 25 amps, including the intake heaters.

 

[storeman]

"I just tested all of mine individually last weekend, pulling the blade connector off each and testing to the frame, all measured just over 6 ohms (6.1-6.4)

Ike"

You are correct Ike. Faulty memory on my part.
Jerry

 

[ZeusDiesel]

OK, thanks, Guys: I have two classes tonite (thurs), will hopefully test these plugs tomorrow, weather allowing (supposed to get up to an inch of rain tomorrow).

ZeusDiesel

 

[ZeusDiesel]

Checked the plugs out over the weekend, 2 showed 5.4 Ohms, 2 showed 6.0.

Using ether, I started the gen and ran it for 5 hours, no load about half throttle checking to see if the piston rings were froze up, thus limiting start-up compression. Ran with out a hitch. Shut it down, 1 minute later, tried re-start with starter only, cranked strong, no smoke. Hooked up air warmer and glow plugs, warmed the plugs for 60 sec., cranked strong, no smoke.

Still open to suggestions.

Thanks again for all your input.

ZeusDiesel

 

[Jimc]

man that really does sound like low compression to me.

 

[steelypip]

If you have the ability to easily check the compression (eg, glow plugs come out and you can quickly borrow/fabricate an adapter and gauge) do so. Otherwise, I'd check:

1. valve lash (can equal low cranking compression)
2. injector timing
3. injection pump shot when cranking (remove an injector, twist a line around so that it sprays in the air, and then go thorough a hot starting cycle (no glow plugs) to see if you get any injection when the starter motor is doing its thing. Bad seals/clearances in a pump might leak down so fast when cranking that you don't get enough fuel to start the engine.

But yes, it's starting to look like low compression or a trashed inj pump.

You did check that the glow plugs were getting voltage when the switch was in the preheat position, right? We're on page 14 of the thread and I've frankly forgotten.

How much blowby does it have under load?

 

[Ray70]

Bill, I've been away from this thread for a while so maybe I missed it, but have you verified the linkag and solenoid next to the IP is moving freely and not binding up?
Also, have you tried starting it with the throttle pushed in rather than at operating speed? One of my units does a similar thing to yours. It will start fine when cold ( using just glow plugs) but if I shut down for a few minutes it won't restart unless I wiggle the throttle linkage and start with the throttle pushed in. When you have the no-start problem are you getting any smoke from the exhaust at all? Again sorry if this info was given already and I missed it.
Ray.

 

[storeman]

Bill, IMO, if you ran for 5 hours, your IP and injectors are obviously working, once kicked into service by the ether.

Not enough cam lobe pressure possibly. You have had your pump off several times. Are there shims at the block (look like pieces of stiff tin foil)? If so, try removing one or two and see if pump responds better to the cam lobe, thus producing more fuel.

Jerry

 

[ZeusDiesel]

Wow, thank you for all the input. I'll do my best here to respond. Yes, I have checked or had Jerry check all of the following and these things check OK:

VALVE LASH, I.P., INJECTORS, GLOW PLUGS, LINKAGE/THROTTLE: engine runs smooth, once up and going.

There is at least one shim on the IP mount. Have not checked blow-by or measured compression yet. I believe the flywheel PC mark was properly aligned when I mounted the IP on the engine, is there any other timing adjustment (in the IP or elsewhere) that could be off balance that would cause a hard start and yet allow it to run?

Thanks again for taking the time on this. Hope I can return the favor.

ZeusDiesel (Bill)

 

[storeman]

To clarify, I've serviced the IP and the injectors. Bill has done the rest. What do the other members think about removing a shim or two from the block to get more lobe contact? This is a generator with over 3,000 hours on it. Granted, the gear tooth lash would tighten, but wouldn't the cam lobe contact also improve?
Jerry

 

[Jimc]

i think that would be the same as increasing the timing button size. its odd though because this engine was running. all i can think of is that its not building enough compression during cranking to fire it off. once running its spinning quick enough. maybe back when the problem started and it was running there was some scoring going on in the cylinders or a couple broken rings. he shut it down and now it wont start. i say get yourself 2 new head and valve cover gaskets, pull the heads off and just check things out. certainly wouldnt hurt or cost alot of money to do so. its really pretty easy to do.

 

[Triple Jim]

Maybe start with a compression test (sorry if that was mentioned previously).