valve seals

[Petros]

usually hard hand pressure will do it. There is a tool to seat them but too much force can damage the new seals, I prefer using my hands (as in most things). You should be able to visually verify this through the springs with the valve cover off. even if not pushed down all the way it wills still keep out the oil, on my old volvo b18 engine the valve seals went on top of the retainter instead of under it, and it worked. Two other sourses of oil leadage from the valves, guides are so worn the stem moves around so much even with new seals it still seeps past (not a real concern but a minor nuisance). This only happens with very high mile engines or if it was run on very dirty or gritty oil for long periods of time. The other cause is if the valve guide itself came loose in the head and it rides up and down with the valve, oil leaks down the outside of the guide into the combution chamber. This is caused from badly overheated or misinstalled valve guilds, it can happen even on a new engine. Only friction holds the guild in (intepherance fit into the head), overheating can cause them to slip and bond to an overheated exahust valve stem. One very good reason NEVER to use the factory 5 deg BTDC timing, but rather run 10 deg or more, keeps the exhaust valves much cooler and less prone to valve damage or burned exhaust valves.

to check for the last you have to run the engine with the valve cover off (make a cardboard sheild to keep oil spray to a min.) and with a strong light inspect the tops of the valve guides as it is running, the top of the valve guild should stay with the head and not go up and down with the valve.

It is also possible but much less likely you have a parcially damaged head gasket that allows oil to leak into the number one cylinder. more likely you will be loosing coolant if this is the case.

Good luck.

[deejay1272]

Thanks for the tips here, Petros. I plan to adjust my valves next time I'm able to spend some time on the Terjunken so I'll push those valve guide seals down with a screwdriver poked between the valve springs to see if that clears up the problem. If I'm smart about it, I'll even remember to remove a spark plug for a given cylinder to test which cylinder is causing the smoke so I don't have to go through each of the 8 valves so maybe I can find a way to save time.

The weird thing is that I'm getting very good results on my compression tests (in the range of 180-190 --- note that I have the 3A-S which is higher compression) so I'm baffled as to why I would have blue smoke other than valve guide seals. My frame has 234k on it, but the motor was installed by some PO a long time ago and it has, presumably, much fewer than that on the clock.

I'll try to push those seals down a bit further when I'm in there to adjust the valves. Between those two actions, I hope I'll be able to make a difference.

[gotama]

still smoking deejay?..did u do a compression test?

[Petros]

none of the problems I outlined above would affect the compression. The condition of the valve seat (and rings and cylinder bore) is what affects compression, not the oil seals.