Hot start issue

[Shikaroka]

My old Burb has always started right up when cold, and always started hot until recently, she has developed a hot start issue.

If I drive for a while, shut it off and get out, then come back in an hour or so, it is really hard to get her started. It cranks over fine, just won't fire.
The glow plugs seem to be working, as the "wait to start" light comes on the normal amount of time. But, I have noticed that if I cycle the key, the light will only flash on for a split second the second and consecutive times.

Most of the time, after a couple key cycles and attempts to start her, she will fire right up like nothing was wrong. But, there have been a couple times that I could not get her to fire up without some persuasion from an aerosol can.

When cold, she fires right up. She seems to be running fine. And usually if she only sets a few minutes, she starts right back up. It seems the only issue is when I leave her setting for an hour give or take.

Any ideas ladies and gents?

[Burning Oil]

Sounds like a pmd. Where is yours mounted?

[Shikaroka]

I was starting to suspect the PMD.
I have it mounted on a heat sink on the intake manifold.

Yes, I know that's not the best place.

I have a new PMD and the extended cable, I just haven't taken the time to put them on. I guess I should look into doing that soon.

Would it still be a failing PMD if a little spray of silicone helps get it going?

[Burning Oil]

Up ontop of the intake is definatly the hotest place you can put your PMD. It actually runs cooler on the IP than in that location.
I would say you have a PMD problem, try installing your new PMD temporarily and see if it fixes it. Get it out of the engine compartment asap.
Leroy

[JohnC]

Most of the time, after a couple key cycles and attempts to start her, she will fire right up like nothing was wrong. But, there have been a couple times that I could not get her to fire up without some persuasion from an aerosol can.

Sounds to me like the injection pump is having trouble building pressure with hot components and hot fuel. Try adding a couple of quarts of 2-stroke oil to 5 or 6 gallons in the tank and see if the added viscosity improves the situation or not.

[Shikaroka]

I just rememered that I hadn't added anything to the diesel the last tank full or so. That could be it.
I just filled up and put in my usual PS and 2-stroke oil. We'll see if that helps.

I'll be moving the PMD soon too, but I'd like to keep the variables to a minnimum.

Thanks guys!

[tommac95]

Diesel pumps finally fail when hot -- cannot build enough pressure at cranking speed . Running on empty will heat the fuel. bv

[Shikaroka]

Diesel pumps finally fail when hot -- cannot build enough pressure at cranking speed . Running on empty will heat the fuel. bv

I'd say that my pump is getting week.
Do they fail at once, or will it just get progressively more difficult to start it?

[Shikaroka]

Sounds to me like the injection pump is having trouble building pressure with hot components and hot fuel. Try adding a couple of quarts of 2-stroke oil to 5 or 6 gallons in the tank and see if the added viscosity improves the situation or not.

I believe you were right.
After adding some oil, I haven't had anymore problems.

I'll probably be replacing the pump this winter.

[JohnC]

I'll probably be replacing the pump this winter.

It'll probably work fine in the winter....

[Shikaroka]

It'll probably work fine in the winter....

Yeh, it has been cooler the last couple weeks too, so that's probably part of it.

I have a new IP setting on the shelf, just waiting to have the time to put it on. I hope I have the time this winter, and then I hopefully can get it done before I start having problems next summer again.
She still has the original pump on her, so I'm sure it's time. I want to do the chains, and cooling system at the same time, that's why I haven't tackled it yet. I need her to be drivable right now and can't afford to be without her for a week or so (about how long it would take me to get everything done).