108D Cylinder head

beelag

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Hi My son has a 97 P reg 108D with 147k. Recently it started dribbling oil from the drivers side rear corner of the cylinder head and has started blue smoking. Starts, runs and pulls ok as normal, no loss of water or oil in water and no water in oil.
I suspect head gasket has gone between combustion chamber, oil gallery and exterior of head joint, consequently on compression stroke is blowing oil and on downstroke is sucking oil in to combustion and hence smoking.
Does this sound feasible and how bad a job is replacing the gasket.
Further complication, 1 cylinder head stud was found to be broken flush with head joint at that rear (probable cause of gasket failure maybe?)
Any tips on how to get broken stud out.

Also any advice on what other secondhand more powerful powertrains would fit directly into this van, son would like a bit more oomph and the current gearbox is also pretty short on synchromesh.

Any help much appreciated.

Billy
 

nickcc101

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S203 C180 auto estate 2001 (sold)
If you have a broken head stud/bolt then the gasket will almost certainly have blown as there will be reduced pressure on the gasket in that area. There are two ways (known to me) to remove the broken stud. 1) Drill out the centre of the broken stud and use easy outs to unscrew from the block. 2) Drill out the broken stud and use a helicoil to replace the old thread. If you need any more advice on either method please let me know.
 
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beelag

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Hi nickcc101
Thanks for info.
Is there enough room to do this accurately with the engine in situ or does it have to come out?
Any preferences for which method of extraction?
Have used stud extractors before (with some successes and some failures) but found I had to be very accurate with drilling the pilot hole and not easy to get the drill started dead centre on the sheared surface which invariably is irreguar and sloping to one side.
Also have had extractors snap in the hole on very tight studs which then makes the whole process even harder with a hardened bit of extractor stuck in there as well.
Maybe I am just a bit ham fisted.
Billy
 

Number_Cruncher

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1995 W124 E300D TE
If the stud was *found* to be broken, rather than was broken in an attempt to remove it, there's a good chance it will unscrew quite easily.

I would say that if you were to drill in using a left hand drill bit (see Ebay item 290313529178 as an example), there's a 50/50 chance that the stud will just unscrew itself.
 
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beelag

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Hi
The stud was found to be broken, whether it sheared in use or was broken prior to us owning it I don't know.
We have done around 30k since buying it and the gasket has just gone now.
 

nickcc101

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Sorry never worked on your type of vehicle. Suggest using tool like a dremmel to grind the stud flat then centre pop before drilling. If the stud comes out using the extractors (yes i've had them break as well) great if not just drill out the whole stud, tap out oversize thread and use the helicoils, make sure that you don't break the extractor or you will never drill it out after. If room to drill is restricted try using angled drill (hire shop). If the stud had broken without anyones knowledge then the broken bit would still be in the head.
 
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beelag

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Cheers, thanks for the useful tips, will pass them onto son and see what he thinks he wants to do.
 

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