leakage test

[stack]

The following values were measured in a recent leakage test of my 2.4S
7%, 10%, 24%, 26%, 28% and 30%
There is no smoke when idling with hot engine. However when going at 4,000-5,000 rpm, releasing throttle and then pushing throttle down again there is a puff of blue smoke noticable.
My question: The car has only driven 6,000 miles in the last 10years. Is there any possibility that the picture may improve by properly driving this car and putting some good miles on it. Or should I go straight through to the dreaded ($$$) rebuild scenario ?

[ttweed]

However when going at 4,000-5,000 rpm, releasing throttle and then pushing throttle down again there is a puff of blue smoke noticable.

This sounds like worn valve guides. On decelleration, the oil gets sucked past the guides into the combustion chamber. How is the oil consumption on the engine? You must be down on power too, with numbers like that, no? You may be looking at a top end overhaul, but it may not be immediately necessary. When the oil starts fouling your plugs constantly, it's definitely time to do something, however, the contact between the valve and the guide is also a path for heat to be transferred from the valve stem to the head (and then dispersed by the cooling air flow over the heads from the fan and shrouding,) so when they get loose in the guide, the heat can build up in the valve stem and cause a more catastrophic failure, dropping the valve into the cylinder, so it may be wise to take a closer look at the valve guides and fix them now, rather than waiting. "An oz. of prevention is worth a lb. of cure," as they say.

Poor leakdown can also be caused by deposits on the valves not allowing them to close completely, but your "blue smoke" symptom is more disturbing than that. I would take the valve covers off and see how much "play" there is in each valve stem.

TT

[mjmoran]

As Tom said...You may not need a complete rebuild and a top-end job is not too bad usually...much cheaper than that dropped valve.