[fluckdowg]

Got a 97 F-250 with the 7.3L diesel. She has a problem worming up when I first start it. It’s almost impossible to get it started on a really cold day, but even on a day when it's been 90 plus all day it will start up but sounds like it's missing on a few cylinders and has no power for about 15-30 min. Once it's wormed up it sounds good and there is plenty of power. I replaced the glow plugs and I’m pretty shure there all working good. Is there an easy way to test them and what else do you think could be causing the power problems when it first starts? It’s only when it's been sitting long enough for the engine to completely cool down.

 

[Nit]

replace teh GPR, more than likely thats your problem, rough startign is GP or injector o-rings, if its only smoking or running rough for a few blocks its GPs, if it smokes for a mile then its o-rings.

 

[fluckdowg]

I’m just a dumb Marine, and still kinda new around diesels. What’s the GPR? I don't think it's the o-rings. it will blow allot of white smoke when it's starting but once it's runnin there is only a little black smoke that comes out when I floor it goin down the road.

 

[fluckdowg]

haha, told ya i was a dumb Marine. your talkin about the glow plug relay right. whats the best way to check the power on that to see if it's workin properly?

 

[jtbel]

All I can give you is a basic answer from my experience. I believe the gpr should have 12 volts going to one of the big posts. When you turn the key, you will here a click and the other big post should also have around 12 volts. The gpr should be just left of the fuel filter. You can test the glow plugs by disconnecting each of the four harnesses going to the 2 under valve cover gaskets and checking the ohms of each of the outer pins (2 at each connection). Resistance should be .5 -2 ohms. The no power might have something to do with the exhaust back pressure valve-do a search for that.

 

[fluckdowg]

i checked out the GPR, and it's all good. i was readin up a little more on the o-rings, and i'm thinkin it might be that. i've done the GP's before, there pretty easy and i'm pretty handy with a wrench. would a compretion test tell me if it's the injector o-rings? or is there any other way you know of checkin them out without pullin'em and lookin at'em?

 

[Nit]

nope not good, forget checkign it, it may pass 12 volts but I doubt it passes enough amps, just go and replace it. White smoke is unburnt fuel adn the only way that happens is without glowplugs working.