From those figures its looking like 3 and 4 head has a compression leak at the cylinder head SEALING surfaces
Boxes, bags and labels for the bits as they come off. I say I'll do it then get carried away and wonder where all the bits bolts nuts came from!.. photos are good reminders too Sent from my SM-G930F using Tapatalk
check all valve settings to begin with( then re-check compressions) set the timing statically, will be more than good enough for a test check all the head bolts, if any are loose then it wants stripping to re-torque them all , have you got a dti gauge ?
Where are you based there must be someone close that may help you. Sent from my SM-A405FN using Tapatalk
These four are under the rocker cover.. the ones where the nuts are off and have green sealant on them.. the top 4 are under tinware.. Sent from my SM-G930F using Tapatalk
I retorqued my heads with the engine in the bus last year. It's doable, but I would investigate any other possible cause first because just about any alternative would be easier. It's fairly pointless just doing the lower easy to get at ones, though I suppose you might learn something by finding loose nuts. However... I don't think you'd get 100psi with loose head nuts.
A loss of 75 psi over the 2 cylinders with 175 psi is a lot. Why don't ya seeing as its the number 4 cylinder and your about ready to drop the engine and strip it.... do this. Take off the number 4 rocker assembly ,remove the push rods and tubes from number 4, pull out the followers for number 4 , (put ya finger in and pull em out). Then lets see what they look like. Note. If the inlet or exhaust valve isn't closing properly when the number 4 is at TDC, compression escapes between the valve and the seat . This could also be why you have a low reading on that cylinder. Maybe the rocker adjusters are set wrong ,with a hydraulic cam there is a certain amount of turns on the adjuster screws that needs to be done from cold and with the cylinder on TDC On a beetle if there is a comp leak at the head you can hear it when you turn over the engine with out the coil wire attached. There is a hiss noise that comes from the bad cylinder .
Maybe if some followers are worn and valves closing too soon, you get that unusually high pressure and the low ones are just a worn out old engine with ok valve operation?
And if you don't actually watch the gauge as you crank, it could still have been building pressure on the low ones? Or If he did say 10 whirls each time, the ones closing the inlet sooner would build pressure more quickly? If it was mine and I had a workshop it would be in pieces. But so would mine if I had the space and all I want to do is look and measure for the pure hell of it.
Could well be Zedders If that's the case check the cam lobes are good by looking through the follower bores, if good.. Buy 8 new followers. Fit them ,set the adjusters properly to get the follower plungers in the right place inside the 8 new follower's and cross ya fingers. When i do hydraulic type 4 cam rebuilds i swap the cam and followers for a mechanical version. If the owner of this motor does go ed and strip it ... throw the cam as far as possible ... fit a standard flat tappet cam, Web cams are best ,but a SCAT C 25 will do.
First off I just want to thank every one so much you have no idea how much I appreciate all of your input, so I have access to ramps now I need to source and engine jack ideally as cheap as possible
A lot of people do that don't they? I had a T2 with a T25 engine and box many years ago - so quiet and torquey, I really liked it...apart from the odd morning when it sounded like a machine gun for a few minutes. First time I thought it was toast until I switched off and had a google. Bliss when the noisy one pumps up though so I think overall, despite the bad rep if I had a hydraulic cam 2L I'd keep it hydraulic. It's a personal thing as much as a technical one, neither will be a racing machine. But...If I had to strip ANY stock engine I owned, I could not put it back together without increasing the capacity as much as possible and the hydraulic cam would go in the process so I wouldn't really ever keep one.