What do you think? Should I rebuild this 300tdi

Hi all

Need your opinions please on the engine condition please....
Finally got my hands on a 300tdi, it's actually still in a discovery 1 MOT fail. It's done 150k miles.

Now the engine sounds sweet as a nut, starts on the button from cold with no blue smoke on startup, Just a small black puff. When cold there is zero puffing/breathing/steam out the filler cap or dipstick, a very slight bit of steam when warm out the filler cap. Only a fraction really that can be seen with a torch in the dark. Is that a sign of wear?

The engine pulls like a train, and the difference is black and white compared to the engine it's replacing in my defender.

I managed to get some compression readings when warm.
Cylinder 1: 380
Cylinder 2: 380
Cylinder 3: 390
Do these sound good to you guys?

Now unfortunately, I stripped the glow plug hole on cylinder 4. I managed to get the glow plug back in and not losing any compression on tick over. What are my options here?

So my question is, it seems to good to strip down and rebuild, when it's running so well. What would you guys do?
Obviously the engine has got to come out. Would you rebuild it? Or Just put a cambelt, clutch and crank seal? Or something else?

It also doesn't leak.

Thanks in advance guys

Well as the glow plug hole is suspect the head should have to come off to sort it,as its off then you might as well do a top end overhaul.

tottot said:

Well as the glow plug hole is suspect the head should have to come off to sort it,as its off then you might as well do a top end overhaul.

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Can't it be helicoiled in place?
How does the engine sound to you?

All I'd do is rear oil seal, p gasket, water pump, timing belt, engine breather, crank seal. The steam thing is perfectly fine it only sounds the same as if you have wet hands on a cold day and you can see the water evaporating. How tightly can you do the glow plug up?

If helicoiling works I've got an old 300 head you could practice on if you want it

Marmaduke said:

All I'd do is rear oil seal, p gasket, water pump, timing belt, engine breather, crank seal. The steam thing is perfectly fine it only sounds the same as if you have wet hands on a cold day and you can see the water evaporating. How tightly can you do the glow plug up?

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Thanks Marmaduke. The wet hands explanation is exactly what it's like, not a sign of worn rings or bore then?

I'm going to check how close I can get the torque on the glow plug with a 1/4" torque wrench. I kind of hope the head hasn't got to come off, seems a shame to disturb this engine.

Marmaduke said:

If helicoiling works I've got an old 300 head you could practice on if you want it

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Thanks mate I might take you up on that. I have found glow plug thread repair kits on ebay. Which is more of a solid insert than like a helicoil (spring). So maybe that would be the best option.

Just not sure how I'd prevent swarf going down the bore.

Personally if there's any chance of swarf going into the bore I'd remove the head, a new gasket is a lot easier, cheaper and quicker to replace than a scored piston and bore

I'd get the head off while you have it out and give it a full clean up! With the glow plug thing, I think that's a must and much easier!

might as well get the cam belt changed, and any other seals/gaskets you can get at done at the same time and a new clutch wouldn't hurt!

Bite the bullet, take the head off or you'll be forever worrying about swarf.

Also consider you'll be starting with a nice new head gaskit

Thank's very much chaps.

So it's looking like head off then and new gasket. Is it worth doing anything else while the head is off? Stem seals? New valves? (Forgive lack of knowledge)
I spose this will be give me a chance to inspect the bores too, and any problems that could occur in future.
Unfortunately, it's had an EGR fitted for all of its life, so I think it's going to be pritty coaked up.

Suggestions to get the engine as good as it gets for a used motor welcomed. Will do all current suggestions thanks everyone

20Nm is the book torque for the glow plugs

Kwakerman said:

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Cheers Kwakerman. It was actually undoing it that spripped it strangely enough. It seemed to pick up the alloy

If it's running well and not smoking or using oil personally I'd leave as much alone as you can including the stem seals.