Hi All,

Out of no-where, my '97 7.3L 250 is hard to start. It takes about three long cranks (whith alot of white smoke coming out), then it will start and seem to run fine.

Any thoughts? Is it the glow plugs? If so, are they hard to change?

Thanks for all of the help!!

 

It sounds like it's part of the glow plug circuit, but it might be nothing more than the relay. Plug in the block heater for a few hours before starting it in the morning. If there's no smoke, and it starts fine, then you're on the right track in looking at the glow plug circuit.
Report back to us, and we'll help you take the next step.

 

I agree with Quadzilla, it sounds like something in the glow plug circuit. Next time you start look at the power meter, it should go down quite a bit with the glow plugs on. Keep us informed of what happens.

 

Hi guys, I'm having the same trouble with my 97, just wondering if the relay is clicking when you turn the key does this mean it's probably good? I'm going to go ahead and change the glowplugs anyway, I just thought I'd ask. Bentonmike

 

Yes, you should hear a click when you turn the key.

 

Thanks for the quick reply. That's what I thought, but it never hurts to have a second opion. Bentonmike

 

I appreciate your responses. I'll plug it in, and let you know what happens.

Thanks again,

Tom

 

sounds like glowplug relay. I usually change the gloplugs every other year, and batteries the oposing year. A relay sounds like your problem though.

 

A little info about the relay I have saved from a reply I did on another site.

With key off you should have battery voltage to one large terminal and nothing to the other large or either of the small terminals.

With key on for the first two minutes or so you should have battery voltage to both large and one small terminal. The other small terminal should show ground. This shows the relay active.

With the key on and after the glow plug cycle has finished you should have battery voltage to one large and both small terminals. The computer activates the relay by grounding the second small terminal thus activating the relay.

It is possible to have battery voltage to both large terminals when the relay is active and still have a bad relay. If the contacts inside are pitted or corroded you may have low amp voltage passing through it but not enough power to actually run the glow plugs.

I have an MS Word document saved with both instructions (complete with pictures) from a fellow member of one of the boards I frequent (Carpentractor) and the originating post of my thread when I replaced the glow plugs on my truck a while back. If you would like a copy send me an eMail with the information you need and what site you saw this on and I will reply with an attachment.

Dave / Believer45