200tdi running very badly please help!

Hi All, well here goes with the story of the poorly 200tdi. Pal bought a 200tdi disco to do a bit of offroading with and decided to build his own snorkel from drainpipe but didnt think to seal it and so you know whats coming next!He decided it would be a good idea to see if it would make a good submarine and so he went straight into a pond where yes it sunk right upto the roof where it suddenly decided to cut out.So like a prick he tried to start it but it was too late the damage had been done. It hydro-locked,snapped the timing belt,bent all 8 pushrods and filled up with water.We towed it home and emptied out all the water changed the engine oil and all filters in the process and then replaced all the damaged parts.The engine then reluctantly started but now smokes very badly and has no power until the turbo comes in and then it gets some of its power back and the smoke lessens.It turns out that there is very little compression on cylinder 3 and none on any of the cylinders and so the valves were then checked and found to be ok .The piston rings are also in good shape so what else can it be?Before this incident the engine made good power with no issues at all.
This one has got a few people scratching their arses wondering whats up so any suggestions would be gratefully received.

Cracked head???

timing??

One or more bent conrods

Thanks for the suggestions but the timing is spot on and the conrods are straight but as for a cracked head i dont know but why should it crack?

Are you sure the conrods are straight because that would explain lack of compression and smoke, happened to one of mine, one conrod bent and engine smoking otherwise running fine.?

Well its either the block thats cracked or the head - as you've said you have little or no compression in all 4 cylinders. I take it to check the rings and valves that you have removed the head and replaced the head gasket???

DEFENDER90-DAZ said:

Well its either the block thats cracked or the head - as you've said you have little or no compression in all 4 cylinders. I take it to check the rings and valves that you have removed the head and replaced the head gasket???

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Must have had the head off to check that conrods not bent (piston height from deck)
Mmmmm cracked head wouldn't affect compression that much and not on more than one cylinder, if engine has been hydrolocked then one or more conrods will be bent, cant compress water

Yep - liquids don't compress , the compression is going somewhere though and having no compression on 4 cylinders points to the head or head gasket if it hasn't been replaced

DEFENDER90-DAZ said:

Yep - liquids don't compress , the compression is going somewhere though and having no compression on 4 cylinders points to the head or head gasket if it hasn't been replaced

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Arr but, if the conrods were bent then the pistons would be lower in the cylinder at the top of the stroke lowering the compression or no comression depending on how bent, it dont take a lot

He said that hes checked they are straight so it rules that out - doesn't it???

DEFENDER90-DAZ said:

He said that hes checked they are straight so it rules that out - doesn't it???

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Probably right but if the pistons havn't been taken out the cant see how they have been checked, maybe they have been out and checked and I have missed it.

Just thinking outside the block

The engine was completely stripped and checked and then built back up with new gaskets but still the same. I personally didnt see any of the parts that were checked but was taken to a garage " who knows what they are doing" and they said everything checked out fine but bent conrods would be the only explanation for all 4 cylinders to be low as a cracked head or block would only lower the compression on 1 or 2 cylinders.The engine was turned over when full of water a fair few times before he realised it was dead.

If they have had the conrods out they would see that they are bent and that would account for the lack of compression - has the garage got a good rep?

DEFENDER90-DAZ said:

If they have had the conrods out they would see that they are bent and that would account for the lack of compression - has the garage got a good rep?

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to be honest i dont know how good they are so i suppose the only sure way of finding out is to strip it again ourselves as they are not rocket science to work on but i dont really have any spare time at the moment.

Can only be a few things like head gasket not sealing or rings not sealing or holes/cracks in head chambers or dare I say it...........bent conrods.........

well garage is CRAP! 4 bent conrods so donor engine is now on its way and then an engine rebuild on the damaged one. The moral here is if you want owt doin properly do it yerself!

Well - glad you got to the bottom of it mate, hope you asked the garage for a refund!!

colinl said:

well garage is CRAP! 4 bent conrods so donor engine is now on its way and then an engine rebuild on the damaged one. The moral here is if you want owt doin properly do it yerself!

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My guess would be that the garage didn't do all they promised they'd done.

landowner said:

One or more bent conrods

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