Another starter question

dyoungen · #1 (**permalink**) 10-31-2009, 03:39 PM

I have a 1987 F250 N/A 6.9. The engine has been slower starting lately, I figure due to the cold. The WTS light came on for just a few seconds and would go out. I had the new set of glo plugs I bought on sale, BERU/motorcraft and changed all the glo plugs. I had 3 dead plugs so I figured that was the problem. After I changed them all, the WTS light came on and went off as fast as before and now I think the starter just died. It's under warranty so I"m not worried. Just a pain changing it out. Right now I"m thinking I have a bad glo plug controller. Is there any way of checking it out or does anybody have an idea what might be wrong? I've changed the glo plugs before but not the controler. By the way, all the dead plugs were not BERU plugs, just what came in the truck when I bought it.

Dave Sponaugle · #2 (**permalink**) 10-31-2009, 04:53 PM

Do you have a volt meter?

When the wait to start light is on, does the volt meter drop a couple volts?

Last winter my relay died.
When I hit the manual glow plug switch, the relay clicked but the volt meter did not drop.
Several tries and when the volt mrter did drop, then the engine would start.

On the 87 and newer controller/relay you can replace the relay with the 86 style relay, direct bolt on swap with the same wire connections, for around 25 dollars.

dyoungen · #3 (**permalink**) 10-31-2009, 07:48 PM

I bought the glow plug controler from O'reilly for $20 and change. Is there a diferance between the 86 and 87? The one I got was for the 87. It has 2 larger studs and 2 small 10/32 studs. Where is the relay located? I got rained out and had to quit. Also I had the starter checked and it checked good 3 times.

Dave Sponaugle · #4 (**permalink**) 11-01-2009, 08:53 AM

Then you bought the relay.

This is an 83 thru 86 glow plug controller that screws down into the back of the drivers side head.

The 83 thru 86 glow plug relay is mounted behind the passenger side battery.

87 thru 94 uses the new style resistance feedback controller with the relay mounted on top of the controller, which is all mounted on the rear of the intake manifold on NA motors.

You can use the 86 relay on the 87 controller, they are the same.
Just unbolt the relay swap the new one in, wire exactly the same way.

That said, check your relay and make sure they did not give you a starter relay.
If they did, there will be a small S and I, one by each of the small terminals, they are not the same electrical connections inside the relay.

Trigger coil in the glow plug relay has one end connected to each of the small terminals.
On the starter relay, one end connected to the mounting strap and one end to the S terminal.

dyoungen · #5 (**permalink**) 11-01-2009, 03:25 PM

Dave: The relay I got from Oreilly's doesn't have the small S and I anywhere but it does look simular the starter relay on the passenger side fender wall. Also when I was talking to the guy behind ther counter I specified the glow plug controler.
I posted the picture of the relay I got if it came thru.

dyoungen · #6 (**permalink**) 11-01-2009, 07:24 PM

Looks like I have a newer system than I thought. I asked somebody local when I couldn't find the controller and after describing what I had, we figured out I have something different. Instead of having the controler that screws into the head, I have the module that's mounted behind the CDR in the back of the engine. Anyway, I changed the relay and I have power to the glo plugs but it only stays on for about 2 or 3 seconds so I guess the module is bad.

Dave Sponaugle · #7 (**permalink**) 11-01-2009, 09:45 PM

Your module looks like the third picture I posted above, that is the new style system.

The controller uses resistance feed back to time the glow cycle.
Because of that, you must use ZD 9 glow plugs, and the glow plug resistance is critical for propper operation.

Resistance on each glow plug should be between .5 and 1 ohm.

One or two burnt out or high resistance glow plugs will cause cycle time problems.

dyoungen · #8 (**permalink**) 11-02-2009, 05:54 PM

Dave, after trying different years and systems the guy at OReillys pulled out the 1990 version you have pictured as the new style system. It was listed for the 1990 year only. I"m not sure about starting to R&R tonight. Is there anything I need to look out for?

dyoungen · #9 (**permalink**) 11-03-2009, 03:43 PM

I finally got the glo plug module replaced and she runs fine. That brings up a couple of other questions. The first time I started the truck the WTS light stayed on about 15 seconds. I thought 10 seconds was for cold truck in cold weather. It is about 70 outside right now but the truck hadn't run since saturday. Another question, on the CDR, I can blow into either end and there isn't any resistance. Isn't there supposed to be some resistance? I know I have read not to use an air compressor but the way mine is, it wouldn't matter.