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Rebuild donor 300tdi engine or not? And stripped glow plug thread Help!


Souster

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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 zeropuffing/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 thedifference is black and white compared to the engine it's replacing in my defender. 

I managed to get some compressionreadings 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 getthe 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 acambelt, clutch and crank seal? Orsomething else? 

It also doesn't leak. 

Thanks in advance guys

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9 minutes ago, vulcan bomber said:

I would happily fit that with just the bits you mentioned replaced.

Only proper option is to fit a helicoil the affected thread or replace the head entirely. 

Thanks Vulcan. It sounds like a healthy engine to you to then? 

I mean the oil is filthy, with a good service and a good run I think it would feel even better. 

Save myself the work and just do the neccessary bits then? (Clutch, cambelt,  and it's looking like head gasket unless I can plug the glow plug hole to prevent swarf)

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9 hours ago, Souster said:

  and it's looking like head gasket unless I can plug the glow plug hole to prevent swarf)

You won't realistically, even 1 bit of swarf dropped in will end badly. head off as the guys say drill/tap and insert helicoil.

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Swarf, whether it melts or not, will go through the exhaust valve and the turbine, causing damage to both, if not sticking to them and causing a leaky valve or an unbalanced turbine.  If you are doing anything that creates loose debris and opens into the cylinders, the head should be removed.

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If it's out then then go round it with a fine tooth comb

Core plugs - don't just check, replace

Gaskets on ancillaries

Head off to sort the stripped thread - fit an Elford head gasket, bought direct form the factory

Valve stem seals

Front and rear crank seals

Front and cam seal

Oil separator - replace

Cam belt and followers

In fact everything - none of it is expensive, none of it difficult, but then it's done

 

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On Thursday, October 06, 2016 at 11:29 AM, honitonhobbit said:

If it's out then then go round it with a fine tooth comb

Core plugs - don't just check, replace

Gaskets on ancillaries

Head off to sort the stripped thread - fit an Elford head gasket, bought direct form the factory

Valve stem seals

Front and rear crank seals

Front and cam seal

Oil separator - replace

Cam belt and followers

In fact everything - none of it is expensive, none of it difficult, but then it's done

 

Thanks for the reply. 

Regarding the stem seals, how does it work regarding disturbing the valves?  Obviously I keep the valves in order, but will they seat and seal as well after they've been removed? 

As you can tell, even though I want to do a good job and have it running perfectly, I'm very cautious to mess with something running so well. In one sense, if it ain't broke don't fix it haha.  But on the other hand, don't want to be a month down the line and have blue smoke on start up.  

 

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Valves rotate as they move up and down due to the helical spring, so there is no reason that removing and refitting them should change anything.  But, lapping them with some grinding paste if you're not going to have them reseated by an engineering workshop would be a good idea.  You'll need a spring compressor to remove the collets for seal replacement, and with the seals off, check for valve stemn and guide tube wear (rocking movement).  Honing the bores is wise if the head is off, and to do that properly, you need to remove the pistons, so check the crank shaft journals and consider replacing the big end and main bearings even if they still have white metal on them.  Check the piston rings, as honed bores with knackered rings are still going to use oil and lose compression.  It's also worth opening up the oil pump to check for scoring inside the casing and the condition of the idler gear bush and shaft.  Check its pressure relief valve for scoring and freedom of operation.

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Thanks for your help chaps.  

Removed the cylinder head over the weekend, and was pleasantly surprised  (for a change with a  land rovery aha) with what it revealed. 

There was no blowing of the head gasket at all, the gasket still had the land rover badge on so could this be the original? And all the bores looked near perfect (from what my little knowledge tells me), all honing marks were consistent and no up and down marks in the bore. No ridges in the bore either, other than 5mm of carbon around the top, which when removed doesn't leave any ridges. 

The head looks good too, no cracking or blowing of any kind. Virtually no corrosion or pitting where the water galleries are. So I'm guessing regular anti freeze changes? 

 

Now,  the main reason for this post... I've bought a new set of glow plugs,  and you wouldn't believe it, I've actually managed to torque all 4 glow plugs up to spec.  Therefor,  the one hole with the not so good thread has tightened down fine. 

Do I leave it be, or get it helicoiled still?  

Any input welcome.  Thank's again

 

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Hi chaps. 

Took the sump off this afternoon, as it needed re-sealing anyway.  While I was in there I decided to remove the big end caps,  and inspect the shells. To my untrained eye I think they look pretty good, however I'm no expert. So I'd appreciate the opinions of you experts please. 

20161018_134754.jpg

Should I replace these shells?  And while the sump is off, is there anything else I should do? 

I then took No.3 mains cap off, a inspected the bottom shell,  which I believe is the one that wears the most. 

20161018_140206.jpg

 

Any input very welcome. Thanks alot

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1 hour ago, Bowie69 said:

Very little wear in all of them.

Now you have them out though.....

Thanks Bowie that's good to hear.  Original shells are sitting on the bench at the moment,  as you say seems daft to refit. 

Should I just buy brand new standard shells then, big ends or mains as well?  

Are king bearings a good make for shells?

Cheers

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Check the back of the existing shells for size, just in case they're non standard, but with that condition, you won't need a crank regrind.  The shells are good enough to go back in, but as the others said, if you don't mind spending on a new set, then new would be better still.  I'd say the big end shells are in better condition than the main bearing you removed, so if you only do one set, do the mains.

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