glow plug removal and voltage question m1009

[dmilkman589]

ok. i have 12 volts at my glow plugs. the truck wont start. im assuming there bad/ burnt out. what is the best way too remove them without snapping the ends off leaving the rest in my engine block. also how many volts should i have at my plugs? 12 or 24. i know this truck was owned by the state so it may have had some conversions done. thank you all

 

[doghead]

I'm assuming there bad/ burnt out

No need to guess, use an ohm meter and test each one. They should read 1-3 ohms each.

The -20 TM has a step by step testing procedure for the complete glow plug system. If you can read, you can follow it.

You question on voltage is a bit more complex to answer. You should measure 12v if all 8 glow plugs are good(and energized). Anything from 12-24v if one or more is bad. Or, 12v, no matter what, if the previous owner resupplied it with 12v and removed the resistor on the firewall.

 

[ctmustang]

 

[Barrman]

Swapping out glow plugs is as easy as doing spark plugs on a gasoline V8 from the same time period. I did a set this morning in maybe 20 minutes. 3/8" deep socket and a ratchet wrench.

Now, if you have older non self regulating plugs. What is in there could have swollen up bigger than the threaded hole and the plug won't come out. That is when you need the puller talked about in several threads.

 

[top_prop]

Swapping out glow plugs is as easy as doing spark plugs on a gasoline V8 from the same time period. I did a set this morning in maybe 20 minutes. 3/8" deep socket and a ratchet wrench.

Now, if you have older non self regulating plugs. What is in there could have swollen up bigger than the threaded hole and the plug won't come out. That is when you need the puller talked about in several threads.

Just like everyone harps on here... when looking into any task with your MV... take some time and read the TM... and when TM is said think more than one manual... start with the -10 operators manual then -20 and finally the -34. the -p manual are exploded parts and wiring diagrams and are very useful as well. They are written with different audiences in mind... what they won't tell you is to small put a dab of high temp anti seize grease (the silver grease I learned to put on brake caliper bolts) on the new GP threads for when you change them next time.

 

[acesneights1]

Ohm meter is ...ok but best way to test is hook it up to a 12v in a vise and see how hot it gets and where. it can ohm out good and still be bad, trust me on that... personally if I go through the trouble to remove them, I change them. 60$ for Bosch Duratherms from Rock Auto. Stay away from Waps. They bplump when ya cook 'em....

 

[Milbikes]

I just replaced the glow plugs in my truck. As the weather got colder, it was taking too much cranking to start. I had three swelled glow plug tips. I did not have the special tool. I needed my truck to get to work the next day, so I had to get it done. My procedure was this:

1. Unscrewed glow plug till it would just spin free but not pull out.

2. With six point socket on the glow plug, I started to 'bend' it up and down, more each time until the glow plug inner part snapped off. I then removed the fuel injector, and used a magnetic probe to carefully fish out the broken tip. I then used a shop vac with a narrow nozzle to vacuum out the glow plug hole first, and then the injector hole.

3. The new glow plug would not screw in easily by hand (they should) so I had to run a tap into the glow plug hole (but not to far...I didn't want to damage where the glow plug base seats).

4. I then used a shop vac with a narrow nozzle to vacuum out the glow plug hole first, and then the injector hole.

5. Installed the new glow plug (AC 60) but the terminals need to be carefully ground narrower for CUCV connectors.

All of the swelled up plugs were Wellmans. I have never come across a swelled AC 60 glow plug.

The truck starts up super-fast now.

This procedure worked for me, but it may be better to get the correct glow plug pulling tool. Bending the old glow plugs up and down to snap off a swelled end may not be best for the threads in the head. H.

 

[acmunro]

I have an OTC brand glow plug puller. It uses the split nut and spacer method. Works good I have never had a tip break off using it.
An alternative method to remove a swelled glow plug is to spin the glow plug out till you get a good seal in the hole and crank engine to blow it out with compression. YMMV

If the tip does break off you should be able to retrieve it from the precombustion chamber through the injector hole. Good Luck

 

[gmjunky87]

quick question, if you are going to replace the glow plugs should the engine be hot or cold?

 

[Warthog]

Cold. No need to burn yourself.

 

[gmjunky87]

Thanks. I was just wondering. I know somethings are easier when warmed up a bit.

 

[that1028guy]

^ You may love your MV like your woman (or better than your woman) But she doesn't need forplay to work on her.

 

[gmjunky87]

haha, classic!