okay, my car began to tick over on 3 cylinders for some reason,, ive changed plugs/leads,, theres a deffo spark on the cylinder that is down....
but when i rev it, it freely revs up on 4..

put on the compression tester just now to check it,,

tested the cylinders and cylinders 1,2,3are showing 140psi,, where as cylinder 4 is down at 80 psi!!!!!! now the car is testing my paitience!

it is a freshly rebuilt engine 1300miles ago,, everything new, low comp forged pistons ect!!!

hopefully it may be the head gasket but aint using oil or water!!!

or a dodgy valve, lifter or rocker..

i have a spare std head but now thinking of stage 3 head,.

my luck!!!


also changed lifters and rockers, hoping i wouldnt need the head off...lol

and still the same!!

 

could be a burnt out valve

 

or a fucked tappet,i had a brand new kent cvh 37 cam kit and one of the tappets let go,resulting in cylinder 3 was down to 65psi but prob fixed now ill post a pic of it soon

 

changed the tappets and followers and still the same!!!!

i hope its either the head gasket or a burnt out or slightly bent valve..

 

the valve shouldnet be bent,unless the belt has jumped a few teeth

 

is the lobe on the cam alright and not worn out i have had that on a customers car

 

whats the difference between a tappet and follower?

 

it may not be a burnt out valve it just mite need lapping in a bit.

 

Do a leak test, that will soon show where the pressure is being lost.

 

i reckon uve got a bolt stuck in the inlet thats jamming open the inlet valve on one of your cylinders!

 

where does a bolt suddenly appear from inside inlet manifold.......

 

from when the numpty lost a bolt when building the head he never found it and its been found in the inlet manifold thats what jammed his inlet valve open and fooked up the valve seat!

 

Ah right so is that actually whats happened then?

 

yup went to his the other day and the bolts been in there for 1300 miles and its just caused a problem!!!!

the bolt has no threads left on it and is highly polished lol!