Best take all GP's out & test with battery to make sure the glow properly. You are moving towards winter on your side of the pond.
Every year about now the cold start problem threads start about now.

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Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

Before I knew better I bought Autolite Glow Plugs. I live in S CA and it is not cold here.

I changed the Glow Plugs and did not have a Reamer. 6 months later when I got a Reamer I removed the Autolite Glow Plugs and found that 2 of them had the tips swollen and I had to use a Vice Grips and a lot of twisting and Spraying with WD-40 to get them out. I was afraid they were not going to come out at all.

I replace the Autolites with Monarks as I had already bought them. Monarks are not good either. One of the Monarks failed a year later.

I replaced them with Bosch over 3 years ago and have had no Glow Plug Failures since then.

There are local places that sell Bosch Glow Plugs but they are like $15-$16 each.

Somewhere in the Forum there is pics of Autolite Glow Plugs where it looks like the tip actually exploded.

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84 300D, 82 Volvo 244Gl Diesel

I think this is what you refer to.

Autolite remanufactured starters, are they any good?

Glow Plug Help


.

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1985 300SD
1983 300D
2003 Volvo V70

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Apply dielectric grease to the glow plug when reinstalling, or no?

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1982 240D - 292,000 miles and counting
Same family for 33 years
Newly rebuilt Monark injectors
Newly replaced clutch
New Bilstein shocks

A never-seeze compound also works.

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84 300D, 82 Volvo 244Gl Diesel

I've never put anything on them. No problems so far.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 401,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 26,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
99 Mazda Miata 183,xxx miles.

I don't think you have to on the Engines with Iron Cylinder Heads unless live some place where it is extremely damp.
I have seen pics of Engines on the Forums that have scaly rust on them. If you live someplace that sort of thing happens it could be a good idea to put something on the Threads of the Glow Plugs; even if it is some Wheel Bearing Grease.

But, on the Engines with the Aluminum Head you need to put something at least on the threads of the Glow Plug.

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84 300D, 82 Volvo 244Gl Diesel