I'm sorry to bother everyone with stupid stuff that is discussed on this board all the time but I just wanted to know how to test my glow plugs. I hook up a test light to the positive on the battery and take the connector off the glow plug and touch the test light to that and it should light up with the key in the OFF position, right? I was just reading on how someone was testing there glowplugs for how long it took them to heat up, how do I do that myself? My truck has 167,000 miles so I basically just broke in the motor and I think I might need to replace a couple or all of the glowplugs. Also my starter died on me and I was able to hit it with a hammer to get it working again and I'm replacing that today. My question is this after driving my truck let's say to work and then it sits for awhile couple of hours then I go to leave for lunch it doesn't want to start. I have to turn the key forward a few times to prime fuel then it will start. I don't know if that could be related to my starter failure or if it could be my injection pump going bad. How can I check the injection pump? One last thing everyone might need to know, I ran out of gas about 1 1/2 months ago and got fuel and had to prime the system and I finally got it running. Could I have got air in the system? Last question I promise where can I order some stanedyne fuel additive to keep the injectors clean because I'm replacing the fuel-water seperator filter and I need to put some fuel treatment in my fuel system last time I did that was 50,000 miles ago. Any help would greatly be appreciated. THANK YOU

 

I replaced all the glow plugs on my truck at 160,000 miles. Once I got them all out I checked them with an Ohm meter. 3 0f 8 showed an open circuit. You can do this on the truck to find out which ones are bad but I would replace all 8. Your truck will start much easier. And if your fuel/water sperator hasn't been changed in awhile that could contribute to the hard starts. Running out of fuel and getting air in the lines is what will cause your starter to go out since you must crank it over alot to get the fuel back into the system. When you change your fuel filter, fill the new one with fuel to eliminate as much air as possible.

 

Navy,
Exactly how do I check the ohm's on my GP's and how do I check to see if they are good or bad. I know I need a test light, I tried to do a search and I can't find anything on how to check. Sorry I'm not too mechanically inclined with a diesal but I do know my gasoline engines well. Thanks, Prince

 

Pull the wires off the glow plugs. With an ohm meter ground the common lead(black) to the block. Put the hot lead (red) on the tip of the glow plug. (where you pulled the wire off) and check for an open circuit. If you do this with an analog meter and the needle doesn't move then you have an open circuit and the glowplug is faulty.

 

p.s. a test light will not work

 

Depending on the cost of the glow plugs (they range from cheap to pricey) and the value of your time you may want to replace them all.

I had an experience where I lost a GP, found it replaced it and a couple of months later got to do it again.

After that, I replaced all of them when one failed. Then I was confident that I wouldn't have to do that again for quite awhile.

Your experience may vary :-)

 

GRiesal, Thanks for the info I'm going home tonight to check on the glowplugs and see exactly what's goin on with them. I will take your advice and replace all the glowplugs.

Navy,
I will use the test light method and the ohm meter to check the GP's and I'll repost.

Thanks for the advice I wouldn't know what to do without this forum.

 

Not sure why a test light would not work. Thats what I've always used to identify burnt out glowplugs on my truck.

 

Ok, guys this is what I did, I checked all the GP's with a test light and ohm meter. The #6 cylinder doesn't light up on the test light. As far as the ohm's go I used the battery for a ground (is that ok??) and I tested all the glow plugs. All the glow plugs were around 1.0-1.4 ohms and #6 cylinder was completely dead, NO OHMS AT ALL. Is that just mean the GP is bad, the motor should be bad right? Let me know, thanks again

 

We need to remember that an ohm is a unit of resistance and therefore your statement is in conflict.

Let me try to explain:

When you are saying no ohms at all, I assume that you are saying infinite resistance, i.e. the needle doesn't move.
This is what you would expect to have on a burned out GP.

Contrast this, with the literal translation of 'no ohms', which indicates zero resistance - a dead short. A dead short should have lit your test lamp up just like the other GPs did.

Bottom line - everything presented here (with the assumptions listed above) indicates that the #6 GP is bad.

I apologize if I have overstated the obvious, but y'all know I like to share the details.

 

After owning my diesel for 10 years and going both ways changing them all or just the bad ones I found out it didn't really matter. Sometimes the same one would burn out a couple times in a row or they would burn out random. It got very expensive in a hurry to change them all every couple months when only one was out. I guess what I'm trying to say is a pack of 8 glow plugs will last for years done one at a time where doing them all will cost you a full set every time you lose one. I say just change the bad ones as indicated by your test light method.

 

As I said, it is balancing act between your time and money.
I have never had a GP fail within months of installing a new one, let alone in the same cylinder. If I were experienciing that modality of failure, I'd be looking at the controller or some other environmental issue including my installation methods and GP supplier.