stuck inlet valve

K

kevinchown

Member
Hi looking for some more guidance, I've managed to get my 1967 200tc running but only one three cylinders, number 3 cylinder has zero reading on compression test so assuming inlet petrol valve is stuck closed. I've tried the usual WD40 through the sprk plug hole then when engine warm engine oil, and so far no luck, anyone got any bright ideas?? :oops:
 
Hi,

number 3 cylinder has zero reading on compression test
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I am thinking that this would tend to indicate that you have either an inlet or exhaust valve stuck open on no.3 cylinder? Either that or some serious problems with that cylinder (cracked wall, failed piston rings or damaged piston......).

Assuming & hoping, it is just a less serious problem with your valves on cylinder 3, you can check by taking the rocker cover off and slowly rotating the engine clockwise by hand. If either the inlet or exhaust valves are sticking, you will see a big gap on the clearance between the top of the valve "bucket" and the camshaft lobe when that valve should be closed. For example, when the inlet should be closed, the clearance should be about 0.010". If the valve is sticking open then, in the closed position, the clearance will be much more than 0.010". Does this make sense?

Is there plenty of oil on your camshaft and around the tops of the valves? If she has been sitting for a while, maybe squirting some fresh oil onto the area around the tops of the valves plus camshaft housing in general and turning the engine on the battery (HT removed from distributor) will get the valves moving again?


If you have valve problems, it could just be something like a failed valve stem oil seal or a bent/corroded valve stem. This is a fairly easy fix but it does mean taking off the camshaft and cylinder head.
 
Hi Gents thanks for the guidance I'm pretty sure that the cam shaft clearence with the buckets on the top of the cylinders is the same as all the others cylinders [hope this makes sense!] therefore the head needs to come off, something I was trying to avoid. Having looked at the manual I need to lock the engine at the 'EP' setting unfortunately the marking is not there! I've lined up the cam lobe for number one cylinder as the book states and the key at the front of the engine is aligned with the space so I can lock it, does that mean it's line up properly???
 
If the camshaft is positioned correctly, then lock it in place and then remove the head. As long as you don't try to turn the crank while it's all apart there's no need to pin the flywheel unless you want to check that it's all timed up correctly.
 
Thanks guys heads off now took me all day and there is no obvious clues as to the problem, except one tappet [least I think that's what its called] is stuck in the spring housing, anyway now head is out I will get it converted to lead free, so thanks for the help.
 
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