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'79 300TD - '74 Triumph Spitfire, '86 Alfa GTV6 & Spider
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24 Posts
Discussion Starter #1
Does anyone know of a good troubleshooting guide/pictorial (like dieselgeek has for the later system) for the early glowplug system? In this case, a '79 300TD, 18mm loop type plugs with the relay under the dash?

Also, does anyone know of a source for an 18mm glow plug reamer that does not cost the earth? Or perhaps a place that will rent one?

I plan to upgrade to the pencil-type fast-glow system, but I want to make sure the exisitng system is working correctly before I start changng things. I currently have an intermittent indicator light issue.

Thanks!

-Kevin

'79 300TD 120K
 

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1984 300D
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5,070 Posts
The cheapest Glow Plug Reamer for your Plugs is still expensive.

I have suggested people use a Stainless Steel Shot Gun Cleaning Brush for the job. Some place on the internet there is a chart with the decimal measurements of the various Shot Gun Gauges.
 

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1979 280CE
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6,118 Posts
On the W123 models the original glow plug relay will work just fine with the new pencil plugs, so there is no need to buy a "fast glow" relay. All you need to purchase are 5 of the upgraded plugs.

Just wire the new pencil plugs up with 10 gauge wire and DO NOT connect the ground wire up to the #1 glow plug.
 

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'79 300TD - '74 Triumph Spitfire, '86 Alfa GTV6 & Spider
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Discussion Starter #6
On the W123 models the original glow plug relay will work just fine with the new pencil plugs, so there is no need to buy a "fast glow" relay. All you need to purchase are 5 of the upgraded plugs.

Just wire the new pencil plugs up with 10 gauge wire and DO NOT connect the ground wire up to the #1 glow plug.
I know this, but the advantages of the newer setup are rather compelling, and the upgrade kit with the relay was not THAT much more than just the glow plugs. Certainly much cheaper than buying the plugs and relay seperately. My plan is actually to just do the glow plugs now, and change the relay setup at my leisure.

I ended up sucking it up and buying the reamer. I will either rent it out to recoup my cash, or just resell the thing. At the mileage I will put on this car, I am unlikely to ever have to do this again.

-Kevin
 
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