Compression Test Failure
#41
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If you do the replacement engine approach, how do you figure out if it's any good? Private sale (if it runs), do a compression test. Commercial (like Jagbits) based on the warranty? Seems like doing the rebuild is a much better approach since you know what you're getting (and how many miles are on the motor).
Thats another reason why I dont want to change the engine, am I replacing a dodgy one with another.
from reading your replies I'm going to hold off looking to replace the engine and look to open the Cam covers and try to get a look at the valves.
I'm really short on time but will try and find some asap, I know no specialist tools are needed for the above but am I going to need some go to ones?
Last edited by Phil m; 08-12-2021 at 05:48 PM.
#42
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Above all you need a decent socket set with extensions and swivels to get to some of the harder to reach bolts on the cam cover. If you don't have what you need Amazon or Halfords have them for very little money.
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Phil m (08-13-2021)
#43
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^^This
If you can lay your hands on a 1/4" or even 3/8" drive kit it will help with those awkward-to-get-to bolts on the rear.
Take note of the upper rearmost bolt on each cover (the ones not captive in a spacer). They're made out of magic metal so as not to affect the cam position sensor and should go back in the same location.
Good luck!
If you can lay your hands on a 1/4" or even 3/8" drive kit it will help with those awkward-to-get-to bolts on the rear.
Take note of the upper rearmost bolt on each cover (the ones not captive in a spacer). They're made out of magic metal so as not to affect the cam position sensor and should go back in the same location.
Good luck!
#44
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Last edited by kansanbrit; 08-13-2021 at 01:52 PM.
#45
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If I had this problem, this would be my simple approach.
If you squirt a little oil in each cylinder and the compression increases significantly, the problem is cylinder wall to piston ring sealing. Engine rebuild.
With no resolution there I'd pull the cam covers and check the primary and secondary chains for security. Rotate the engine to align the flats on the cams to make sure they're in sync. If exhaust cams don't move, the secondary timing chains are your problem, probably tensioners. Hopefully the pistons are OK because a valve and piston did not meet in anger. Keep fingers crossed.
If neither cam moves, the primary timing chains are the culprits.
If that's all OK and the cam flats align and the compression does not increase from the added oil, the heads are coming off and once they're off you'll probably find the problem upon inspection of the heads.
Good luck and please keep us posted.
If you squirt a little oil in each cylinder and the compression increases significantly, the problem is cylinder wall to piston ring sealing. Engine rebuild.
With no resolution there I'd pull the cam covers and check the primary and secondary chains for security. Rotate the engine to align the flats on the cams to make sure they're in sync. If exhaust cams don't move, the secondary timing chains are your problem, probably tensioners. Hopefully the pistons are OK because a valve and piston did not meet in anger. Keep fingers crossed.
If neither cam moves, the primary timing chains are the culprits.
If that's all OK and the cam flats align and the compression does not increase from the added oil, the heads are coming off and once they're off you'll probably find the problem upon inspection of the heads.
Good luck and please keep us posted.
Last edited by stu46h; 08-13-2021 at 05:43 PM.
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dfbender (08-15-2021)
#47
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I circled the 2 spots in red where it looks to me like the valves have made contact with the piston. I would guess that the timing chain on that bank has jumped 2 teeth.
Solution would be valve job on both heads and new chains, guides, and tensioners. There is a chance that there might be
damage to the piston and rod when it hit the valves. Damage could be to the wrist pin or rod bearings. There maybe no damage but if there is you could throw a rod at a later date. It has happened to me once.
I would still take the cam covers off and and align the flats. If you align the flats on the left bank and the right bank is noticeably out of alignment it will confirm my diagnosis.
My opinion is a replacement engine. I would try to find the history of the engine if you can. I like to get an engine out of a car that has been in an accident. At least you know it was running before it got in the accident.
#49
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The second think you know is that on one piston you have zero compression. The piston does appear to have valve impact. Anyway a visual inspection will at least let you know if the tensioner has failed so you have to remove the valve cover on that cylinder bank.
Also one other check you may want to do would be to pull the oil pan off and look for metal and plastic in the sump. If there is a lot of metal there then it may indicate the amount of damgage to the engine. Pulling off the oil pan off is not difficult. If the tensioner did fail and the engine had metal to metal contact the sump should have residue plastic and metal.
None of these inspections will cost much and will hopefully give a better idea of what is going on.
#50
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Thanks again for all the great advice all, because of work commitments and that I might have to move the car to another storage place I'm going to take some time and work out what I want to do.
Option 1 - Reconditioned engine.
I could easily be back to where I am after spending 1000's'
Option 2 - Change the secondary tensioners along with open the head up to check the valves & pistons.
Option 3 - sell the car at auction.
I like option 2 but If either the tensioners, Pistons or valves have gone how likely is it that it has killed the engine too?
I found a really good step by step guide to changing the tensioners, it even includes tools and replacement parts you need to buy.
Option 1 - Reconditioned engine.
I could easily be back to where I am after spending 1000's'
Option 2 - Change the secondary tensioners along with open the head up to check the valves & pistons.
Option 3 - sell the car at auction.
I like option 2 but If either the tensioners, Pistons or valves have gone how likely is it that it has killed the engine too?
I found a really good step by step guide to changing the tensioners, it even includes tools and replacement parts you need to buy.
#55
#56
#57
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Please ONLY turn the engine clockwise when looking from FRONT of the engine.
#59
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When you are able to get to it have a breaker bar and a good 6 sided socket (24mm I think?) handy so you can turn the motor to see valve operation and that the flats on each of the camshafts line up... is it 24mm?
Please ONLY turn the engine clockwise when looking from FRONT of the engine.
Please ONLY turn the engine clockwise when looking from FRONT of the engine.
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