I just brought home a 1988 F-250 7.3 liter IDI N/A single cab 4WD with a 8' Western plow. I have never owned a Ford before and have some questions.

It is pretty hard to start when its cold. Once I get it running it is smooth and seems to run very well. I think the batteries need a good re-charging and I think the glow plugs are probably shot. This weekend I will charge up the batteries and pull the glow plugs to inspect them and replace if necessary.

If the glow plugs are in good shape, I would assume I need to check the relay (if there is one) and the GP fuse. Could someone please give me some info as to where the relay and fuse are located?

This and any other info on this truck would be greatly appreciated!

 

Don't know locations on 7.3, except solenoid, it's on the fender I think. But, I replaced GP's and controller in my 6.9 with same symptoms and it cranks quicker than most new ones. Enjoy!

 

the glow plug relay is either behind the plentum or on the passenger side valve cover...
and i would do a contunity test after un plugging each glow plug and doing them one at a time....
usulally its the controller.... also just a tip.... keeping the block heater plugged in makes it start eaiser and reduces load on the batteries and the starter.... will get ya through till ya can afford batteries..( assuming thier weak )...
i keep mine plugged in and it dosent make a big power bill difference but it does go up bout 50 bucks every month..... pays off ...... truck warmes up quicker and makes better fuel enonomy when warm.... just a tip

 

Thanks for the help.

The controler is behind the plenum and it clicks when energized. The batteries seem to be in good shape (full of water and currently at 12.2 volts) and I have the charger on them. Its about 90F outside, unless you think otherwise, I wouldn't think the block heater will help much.

All but about 3 of the glow plugs show OL on my ohm meter. I believe this means that there is an open in the plug meaning the plug is shot. I will replace all the plugs with motorcraft GP's and hopefully that will fix the hard start.

I sprayed the GP's with some WD-40. They look very straight forward for the remove and replace. If you guys have any special tips for changing them out or any other tips in general, I would appreciate them.

Thanks

 

"Glow plug removal article"

 

I changed my glow plugs, put in new batteries, and replaced the stock glow plug controller with one I got from a guy on e-bay. It allows you to determine the length that the glow plugs stay on. Those 3 fixes made my 200,000 mile 7.3 start like it was new.

 

Very helpful. Thank you very much.

 

How are the cylinders numbered on a 7.3? As in on the drivers side bank is it 1,3,5,7 or is it 1,2,3,4? I need to know this in order to put each cylinder at TDC during the glow plug removal.

Also, if a glow plug is going to break during removal, will it break while turning the GP with a wrench or does the bulged tip just prevent it from exiting the hole after the threads have already been turned out of the head and then you have to break the plug to get it out?

Thanks

 

there ya go

 

DieselCrawler

Thank you very much for all of your very helpful info! Also, thanks to the others how have posted helpful tips and info as well. I really appreciate all of this help and I will post the results of my work on this truck as time goes by so that you won't feel that your time and effort helping me out was not wasted.

I believe next Monday I will be attempting the GP remove/install. I will keep you posted.