MEP-002a won't initially stay running

[Hectorsosa]

Apologies if this has been previously covered - I have an MEP-002a with almost 400 hours on it that recently started giving me trouble. When I start it everything is fine until I let the switch move back to the run position. Initially it acts like one of the safeties is tripping and cuts fuel. If i turn the switch back to start a couple times it will eventually stay running.

Yes I know it's likely a safety, but being that it's intermittent I'm not sure how to troubleshoot. Do the symptoms I describe point toward any one specific safety, or is it time to start replacing parts until it behaves?

 

[Guyfang]

Do you have the TM's downloaded?

Are you abler to understand how to use the schematic?

Troubleshooting saves money. Changing parts cost money.

 

[Hectorsosa]

I have the TMs and I mostly understand the schematic. If you're referring to the plate on top of the unit mine is sun faded and hard to read.

I guess what I'm getting at is it doesn't work until it does. I'll use this example - the oil pressure switch is open until there's oil pressure, then the switch closes. Let's say I did the troubleshooting and it seems to be the oil pressure switch. If my oil pressure gauge isn't 100% accurate I replace the switch only to find out the seals in the oil pump are going bad. I've never HAD to troubleshoot this generator as it has always just worked. I'm not entirely sure where to start.

Should I be looking anywhere in particualr in the TMs? Example - is there a symptom/solution flowchart somewhere?

 

[Guyfang]

Indeed. There is troubleshooting in the -12 and -34 TM. Something quick to check is to jump the safety circuit. Hook a wire up between TB5-8 to TB5-9. That jumps the S4 and S5 safety switches. See if it runs then.

 

[rickf]

First and foremost are you getting oil pressure right away or is it lagging up to the point where the unit stays running? Try bypassing the oil pressure safety but if that solves the problem you REALLY need to see why you have no oil pressure. Actually you need to see why even if it doesn't solve the problem. Check the oil level.
And do not take offense to what I am saying! I have had so many people tell me that they are positive the car has oil in it and when I get there it is down 4 quarts and the engine is fried. This is why I say these things.

 

[Guyfang]

First and foremost are you getting oil pressure right away or is it lagging up to the point where the unit stays running? Try bypassing the oil pressure safety but if that solves the problem you REALLY need to see why you have no oil pressure. (Jumping the S5 and the set running, is not just an indicator of low or no oil pressure. It can also mean the S5 is bad. Jumping the S5 and it works, tells you to first check oil pressure with a gauge, and if you have oil pressure, to check the S5. I would check the S5 first. Less work. )Actually you need to see why even if it doesn't solve the problem. Check the oil level.
And do not take offense to what I am saying! I have had so many people tell me that they are positive the car has oil in it and when I get there it is down 4 quarts and the engine is fried. This is why I say these things.

Open to see comments.

 

[Guyfang]

LOP troubleshooting

 

[rickf]

Remember Guyfang, the 003 has a mechanical oil pressure gauge staring right at you so you can see the pressure as you start. My safety failed but the oil pressure gauge showed I had good oil pressure.

 

[Hectorsosa]

I've got pressure on the gauge moments after it starts firing. Oil level is full on the stick. I only used the oil pressure switch as an example, but I also know there isn't exactly dozens of safeties on these units. I'll jump TB5-8 to TB5-9 and see what happens. Thanks everybody.

 

[Chainbreaker]

I've got pressure on the gauge moments after it starts firing. Oil level is full on the stick. I only used the oil pressure switch as an example, but I also know there isn't exactly dozens of safeties on these units. I'll jump TB5-8 to TB5-9 and see what happens. Thanks everybody.

In fact, there are only 2 safeties. Oil Pressure & Temperature. Oil pressure switch is a relatively common failure, temperature switch not so much.

The other possibility for running & then stopping might be a fueling issue due to electrical or mechanical issues. First eliminate the two more common above before moving on.