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I've only done it on OHV engines, maybe their valve stems project more.
 

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Discussion Starter · #23 ·
Small update. Head rebuilt and engine is now back together. Was fun to do. Only problem is there is still a compression problem. This must be a timing issue now surely as everything was checked when the head was off. My timing tools came and everything lines up. Any ideas anyone ? I noticed with this VVT business that the camshaft sprockets have a degree of movement seperate to the cams themselves ( if that makes sense ). Could it be something to do with that ? In some way these are out which would effect the valves opening at the right time?
 

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Did you use ALL the tools to set the timing, the plate in the slots to lock the cams, lock the sprocket with the sprocket tool before fitting the phase disc's ,etc,etc, if its not done correctly then you will have problems, read from 56 in this link, it shows you how to do it correctly, unless you have already done it this way,...
 

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Discussion Starter · #25 ·
Thanks for the link. Yes I followed that sequence although through a haynes manual but it's the same. Used all the tools as described. Cant get my head round where its going. Tempted to invest in a leak down tester. At least i can pressurise the cylinder and get an idea wheres its going. Cant help think its something obvious
 

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Are you sure its no compression, when these dont fire up and just spin over it does sound like no compression, have you done a pressure test to see what you got.
 

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Just a suggestion, but did you squeeze all the hydraulic valve adjusters up in a vice to get the oil out of them?
If they are holding the valves open, then there won't be any compression.
 

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I didnt. Ill take a look at them. Thanks
If you take the cover off, try moving the rocker when it's on the back of the cam, you should be able to feel some small amount of movement there.
You only need one tight on each cylinder to loose compression!
 
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Discussion Starter · #31 ·
Another update. Bled all the hydraulic lifters. Did another compression test. Have some compression now but unfortunately only 15 to 25 psi on esch cylinder. Wet test didnt make a difference either. Same figures wet and dry 😶
 

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What happens if you line up the crank pulley marks, so mark on the timing chain casing with the mark on the pulley, can you insert the timing tools ok.
 

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Discussion Starter · #33 ·
I wasnt aware the cover and pulley had marks on them. Ive always just put cylinder 1 at TDC and inserted the tools that way. Do you have any pictures of what to look for please ? Im convinced its still some timing issue. Even the engine was overheated for all cylinders to have the same result makes me think its not caused by another mechanical issue 🤣
 

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Discussion Starter · #35 ·
Delayed updated. Been away with work so didnt get the opportunity to check it all again. So the timing marks all line up and still the same results. Ive ordered a leak down tester today. At least it will show where the compression is being lost.
 

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Discussion Starter · #36 ·
Update re leakdown test. The tester i Got seems to be rubbish....my own fault for buying cheap I guess. Using the test adaptor I hooked up the compressor to find where the air is leaking. As per the previous leak marks when I took the head of it was cylinder1 into 2 and cylinder 3 into 4. Took the cams out and valves seem to be holding ok. No air coming through the exhaust or throttle body. I know the head is flat as it has been machined so leaves me thinking it must be the block and my checks werent good enough. Second hand engines start at 500 upwards and there is no way of telling truly what the engine is like so im thinking to take the block to my machinist and see what he thinks. He can check the roundness of bores etc and whether it can be saved. If so I may as well rebuild the bottom end and if possible try and salvage this engine. Anyone any experience with these blocks being warped like this?
 

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I’m not familiar with this engine but I presume it uses a multi layer steel head gasket and torque to yield bolts.

You don’t say whether the previous owner tried any bodge repair on it but you’ve had .6mm machined off the head which means, on some engines, you need to use a slightly thicker MLS gasket.

I don’t know whether you replaced the TTY bolts but if you re-used them in the stretched condition, combined with the amount of material machined off the head, they may be bottoming in the threads. If that’s the case you won’t get the correct clamping force on the head gasket so won’t get proper cylinder compression.
 

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The throttle plate hasn't got itself jammed completely shut has it? I've seen this on a few diesels where the anti shudder valve (the diesel version of the throttle) has got stuck closed - telltale sign is a no start and sounding like no compression. Engines can't compress air they can't draw in.
 
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I don’t know whether you replaced the TTY bolts but if you re-used them in the stretched condition, combined with the amount of material machined off the head, they may be bottoming in the threads. If that’s the case you won’t get the correct clamping force on the head gasket so won’t get proper cylinder compression.
I had similar problems with a Bedford RL breakdown lorry, that kept blowing head gaskets.
The studs had stretched, and the head nuts were dome topped, and were bottoming out.
A couple of flat washers under each nut cured it!
 

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Bedford RL,bloody hell that takes me back a bit Alan, ;)
those old Bedford (300 ?) petrol engines could be a sod to get the heads off sometimes
due to the studs rusting solid in the heads :censored:
 
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