Anyone Clean their Glow Plugs?

[tgtaylor64]

My M1009 was having a hard time starting; plenty of smoke and turnover but no start. Checked voltage at bottom of GP relay and had >11 VDC. Decided to remove a few plugs to check their condition. None were swollen but they all showed a lot of charred residue making them hard to slid out. I assumed this crud was acting as an insulator thus reducing the amount of heat transferred. I placed them in a drill and used some fine grit sandpaper to clean them up. After cleaning, they all looked new and slipped into their holes with ease. We had a cold morning here in the South over the weekend and it got down into the upper 20s. It fired up after one cycling of the GPs! At around $80 for a set of AC60s, this may be an option for some of you.

 

[patracy]

They're exposed to the combustion process every other rotation. That's not residue, that's the actual glow plug expanding. Your sanding just reduced the insulating compound. Evenutally they will swell to the point where they will not remove from the cyl heads (without a puller) or the tip will break.

Did you follow the troubleshooting steps of the TM to ensure the glowplugs are still serviceable?

 

[doghead]

Did you test them with an ohm meter? If not, your wasting your time.

The phrase, "polishing a turd" comes to mind here.

 

[85CUCVtom]

I second Doghead, here's a testing procedure almost word for word from the TM:

Disconnect each glow plug lead and check for resistance between glow plug terminal and ground. Resistance should be 0.45-3 ohms for the Wellman plugs or 1-3 ohms for the GM plugs. Check glow plugs for looseness or damage. If any glow plug does not have correct resistance or is damaged, replace it. Tighten any loose glow plugs.

More can be found in the -20 TM