Grey Motor no compression

[paddockbasher]

I have a grey "J" motor that has been stored for (I think)a number of years.

After spraying penetrating oil in the bore it turns quite freely; however despite spark at the plugs it will not fire. I did a compression test which revealed extremely low compression on all cylinders which did not improve when a little oil was introduced to each of the cylinders.

The engine presents well with evidence of new gaskets throughout, welsh plugs,clean oil and little residue in the sump or underside of tappet cover.


Would anyone know if the low compression could be caused by stuck valves? and if it is possible to remedy/check without removing the head?

Has anyone experienced an engine with extremely low compression on all cylinders; is this typically what happens through excessive wear/age or a catastrophic meltdown?

Appreciate any help/suggestions

[peterwmh]

You could do the old hammer valve loosening trick.  Just remove the tappet cover and give all the rockers on the valve tips a tap to check for movement (I emphasise tap, not hit!).  If they move freely then the valves should be OK.  They may have been overtightened causing the valves to ride, so that may be worth checking too.

Peter

[paddockbasher]

Thanks Peter

Ended up removing the head. Valves definitely stuck. Off to the local repco for cylinder head work.