Dang, I don't know for once... Hard start

[adrianspeeder]

Never bothered to research troubleshootin' 7.3L's because mine's never had a problem. (Just wish I had it down here on base )

Anyway, borrowin' a friends '95 250 with 220k hard miles, and this mornin' at only 50deg thing wouldn't fire off. But it made one hellovea white smoke show to block out the view of the '79 dually next to it. After five or so crank cycles it came to life and the smoke cleared right out to normal light blue.

Quick search around the board shows glow plug harness fault?

Adrianspeeder

 

[Mike]

Glow plug relay.

 

[h2odrx]

Thats what I've heard.... Mine did that too, but it fires off any other time without a problem, I'm thinking oil change too?

 

[Crumm]

GPR

Do yourself a favor and replace it with a Stancor 586-902 relay rather than a stock type.

 

[adrianspeeder]

Anyone gotta wiring diagram handy so I can throw a meter on there?

Wheres the source for the better relay?

Adrianspeeder

 

[geonc]

Speedy, the GP relay on the PSD is no different [in operation] than any found on the IDI -----SPNO 12v

The Stancor is perferred due to it's larger, full nickel contacts.

It is mounted on top of the engine, just to the passenger side of the fuel filter----under the removeable/ hinged fuel filter access cover.

The WTS cycle is also that of a properly functioning IDI--- +/- 12 seconds.

While you have out your DVM, remove the connectors at the valve cover gaskets -2 each side---check the ohms at the outermost pins--these are for the GP's--- 1.0 and under is OK----anything above

 

[geonc]

Woops! fergot a link

Stancor 586-902


You can get by with a stocker from Navistar or NAPA.

 

[Crumm]

Allied Electronics also carries them. Been a few years since I purchased mine but if I recall Mouser Electronics is a little cheaper on the relay but once they both figured in shipping Allied was cheaper. This was a few years ago and shipping is usually high to Alaska so it could be different for you.

 

[adrianspeeder]

Just got the relay in, havin' trouble figurin out which of the smaller wires do what...

Adrianspeeder

 

[Mike]

Just put the big wires on the big terms and the lil ones on the lil terms.... its so easy a caveman could do it.

 

[adrianspeeder]

Just put the big wires on the big terms and the lil ones on the lil terms.... its so easy a caveman could do it.

Figured that much, and can determine which of the secondary wires go where, but want to know what the individual purpose of the small primary wires is.

Adrianspeeder

 

[geonc]

Figured that much, and can determine which of the secondary wires go where, but want to know what the individual purpose of the small primary wires is.

Adrianspeeder

signal and trigger to hold in

 

[Mike]

signal and trigger to hold in

What he said........... big wires are the brawn from the batts and little wires are the brains from the PCM.

 

[adrianspeeder]

Aight, new ordered relay, new batteries, new cables, new plug on the block heater, and no start when cold and unplugged.

Pulled the connectors to the valve cover harness on the passenger side and had open continuity to every pin. Wasn't sure which were for the glow plugs so checked em all.

Any quick tips for when I put new ones in tomarra mornin?

Adrianspeeder

 

[subway]

Any quick tips for when I put new ones in tomarra mornin?

Adrianspeeder

when you get tired of walking you can just **** in your shoes and swim