Glow plug relay question

[dstang97]

How come the st85 are so much money? napa wants 65 dollars. What is the difference from using a dog head relay or any other starter relay?

 

[unaffiliated]

Not sure what the difference is but I used a S55 relay from my local Mom and Pop auto parts store that is traditionally much higher than Advance or O'Reilly and it was only $42.00. Another SS member said I should get either the ST85 or the S55. My local store only had the S55 so I got it and it worked great. It looked a little different than the original but who cares as long as it works, right.

 

[cpf240]

The GP relay requires an isolated ground for the GP controller to function properly. That is about the only difference that I can think of.

 

[chevyCUCV]

I was never sure when i replaced mine. I bought the st85 for 50 bucks i think.

Later on while at the local auto place i asked them for a gp relay and they just pulled a plow relay off the shelf, same as the dh relay and any lawn mower relay.
Next time i will use one of those for $10

 

[M1008driver]

I used this one and thought it was pricey at $49.99. It works too.

BWD S603 - Solenoid | O'Reilly Auto Parts

 

[tamecrow]

There's a guy on Ebay selling them for $9.00 each. I bought one 10,000 miles ago, and it still works like it should. Just look up 'cucv glow plug solenoid'. Hope this helps.

 

[wes935]

There's a guy on Ebay selling them for $9.00 each. I bought one 10,000 miles ago, and it still works like it should. Just look up 'cucv glow plug solenoid'. Hope this helps.

Just ordered two of these on Saturday night and they arrived in the mail yesterday. Hope this solves my problems. The old one tested bad per tm-20.
I also installed new AC 60G's with new terminals, resistor bypass getting power from the 12v bus bar, and replaced fuel filter. I bled the fuel line after replacing the filter, but still no start.
Glow plugs take a long time to cycle now (45 seconds) and the clunk is now barely noticeable.

 

[mistaken1]

Functioning glow plugs draw something on the order of 80A. The power contacts on the relay have to be capable of carrying that load as well as breaking that load.

 

[K9Vic]

I bought a Wells F496 solenoid (Ford) for my GP system on my M1009 and seems to work well after a few starts. I have always used the ST85/S603 in the past but for some reason I got the Wells F496 probably due to an error on my part as the alternate part number is SW85. So my question is that since I have already installed it I cannot return it. It is a continuous solenoid, but I cannot find anything on the amp rating. Being that it is for a Ford starter I am thinking it will be rated enough amps for the GP system, about 80amps. Will this be OK, or should I get the ST85/S603

 

[dstang97]

I bought a ford relay also. It works fine. Post a picture of it. Mine was like 25 bucks.

 

[K9Vic]

I have the same relay in my M1010 that was always there, or at least same look with the black case. Here is the picture, I still have to put a rubber cover over the top post.

 

[doghead]

The term "Ford relay" is very confusing and misleading.

The important thing with the glow plug relay is, it needs to have an isolated from ground(chassis) coil.

The original glow plug controller switches the negative/ground to the relay coil. Positive/+ is always "on" on the relay coil.

Normal "Ford" starter relays are grounded through their chassis/mounting bolt. They are not compatible with the original CUCV glow plug controller. If the relay has an "S" and "I" next to the small terminals, it is most likely NOT compatable with the CUCV GP system.

Test any relay before you install it, to be sure. It cannot have any continuity between either small terminals, to ground/chassis/ it's mount ears.

If you install the wrong relay, you may ruin your controller card and also burn out your glow plugs.

 

[allenhillview]

The term "Ford relay" is very confusing and misleading.

The important thing with the glow plug relay is, it needs to have an isolated from ground(chassis) coil.

The original glow plug controller switches the negative/ground to the relay coil. Positive/+ is always "on" on the relay coil.

Normal "Ford" starter relays are grounded through their chassis/mounting bolt. They are not compatible with the original CUCV glow plug controller. If the relay has an "S" and "I" next to the small terminals, it is most likely NOT compatable forth the CUCV GP system.

Test any relay before you install it, to be sure. It cannot have any continuity between either small terminals, to ground/chassis/ it's mount ears.

If you install the wrong relay, you may ruin your controller card and also burn out your glow plugs.

So the ST85 is the correct one( always) because of the isolated ground?

 

[dstang97]

Yes st85 is in the FAQ as the right one. I bought a gpr100 which is also inthe FAQ section. It says it's for a ford gpr

 

[mistaken1]

I went to O’ Reilly auto parts and bought an isolated coil relay (BWD P/N: S603 - $48.99).

Been using it once a week or so for the past year.

 

[doghead]

One other tid bit of info to consider. The Glow Plug Controller card is designed for a specific range of output load(the relay coil). You could see a variation in performance, depending on how far from OE spec, your relay coil is(if you choose any old relay).

 

[allenhillview]

One other tid bit of info to consider. The Glow Plug Controller card is designed for a specific range of output load(the relay coil). You could see a variation in performance, depending on how far from OE spec, your relay coil is(if you choose any old relay).

hey and Hello again, you are saying....? the st85 will be right reading for the controller card output?

 

[doghead]

The st85 has proven to work well.

 

[dstang97]

The st85 has proven to work well.

What do you think about the gpr100?

 

[doghead]

I have no experience with a gpr100 relay. It looks to be an "economy" choice from NAPA.

I am not sure of it's internal design, but it looks to be used in some GM diesel vehicle applications.

I'd test it for compatibility, before installing one.