Compression Test, Not Sure What To Make Of It ?

[tomtaylor1]

Hi, I have done a compression test on my newly purchased 1967  Caribbean, 1.3.

I New when I made the purchase the engine had some problems, burning oil, noisy valve gear.

On a hot engine, all plugs removed, the readings where as follows.

Cylinder 1, 145 psi 2, 160, 3, 160, 4, 145 psi.

When a squirt of oil injected into each bore via the plug hole, the readings were as follows,

Cylinder 1, 185 psi, 2, 220, 3, 210, 4, 185 psi.  

How should These readings be interpreted, faulty valve seals or seats, or worn pistons or and bores, or a combination of all.

Thank you in anticipation, thank you, regards Tom 

 

[tomtaylor1]

Sorry slip of the finger, 1997 Caribbean.

Regards Tom

[stubuzz]

Worn piston/rings/bores.

How many km on the engine?

[canthai55]

Stu beat me to it. If after the oil squirt test the compression does not increase, problem lies in the head. Valves most likely. Assuming that two adjacent cylinders do not show low compression together - then throw in a possible head gasket failure between the fire rings.

[JAS21]

I have always done a compression test over four cranks of the engine and with the accelerator to the floor.

Noting what value the pressure rises to after at each rotation. That gives more information.

But as everyone has said it points to a piston ring problem/ worn bores ...

 

Edited August 2, 2016 by JAS21
Little more info ...

[gdgbb]

3 hours ago, JAS21 said:

I have always done a compression test over four cranks of the engine and with the accelerator to the floor.

Noting what value the pressure rises to after at each rotation. That gives more information.

But as everyone has said it points to a piston ring problem/ worn bores ...

 

The engine isn't going to fire so why bother with the accelerator position?

[tomtaylor1]

Hi All, thank you, the compression test for a new engine should be 180/200 PSI, so worn bores/rings appear to be the problem.

Regards Tom

[Lickey]

I would say that a 19 year old engine with all the different fuels,the climate,the dust and the heat,possibly a clogged radiator its a case of its worn out,

 If it runs sort of ok, leave it, stripping it down will reveal so many worn parts it would be expensive to put right.

Perhaps look round the scrap yards for a low mileage write-off.

[tomtaylor1]

Hi Thank you, have posted a question, about which engines would be suitable to transplant into the car, hopefully keeping the original gearbox, thinking a fuel injection engine would be the best option, also LPG mixing is installed in the car, would like to keep this in some form or another.

The speedo shows 98000 kilometers. 

Regards Tom