Changing valve oil seals with heads still on?

Whist the cams and followers are off for repair I was thinking I might take a look at the valve stem oil seals as they must be at least 20 years old!
Does anybody have a process for changing these with the heads still on as I am not keen to go any deeper into the engine.
My bike is a 1984 VF1000RE
Thanks in advance

Many moons ago I purchased the tooling for doing this,its awkward and time consuming and frustrating as.

You are four bolts and two pipes away from having a head off why not just go for it.
Do a decoke and lap the valves in while your at it and make it worthwhile

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I am a bit concerned about disturbing the large gear wheels. I have set the machine to TDC 1-3 on compression and don’t want to move it until the cams are back in…at the very limit of my skill and confidence with this but enjoying it!
Also if I do take the head off would I need to have the head skimmed to refit?

In the past I had used compressed air in the spark plug hole ( may need to make a screw in fitting same thread as the spark plug ) to hold the valves in place whilst removing the springs and collets.

Good luck


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The gear drives are much easier to manage than camchains and tensioners. There are no timing markings on the gear sets, you just bolt them in. All you have to remember is keep the front and rear gear sets in the same cylinder banks.

Thanks Don, I’ll think I will have a go at it.
The bike currently runs quite well with no leaks around the head gasket…what would you think the likelihood of needing to skim the head would be if I remove it?

I used an old sparkplug and completely gutted it and cleaned it up really good to make sure no ceramic bits got into the bore. Then I braze welded an old male air line fitting to the plug. Screw the plug in with your plug spanner and attach the air line. If all your valves are ok, then the cylinders should hold the valves in place. You can buy rather cheaply a special type of puller that you attach to the base of the spring and tighten it to compress the spring enough to remove the collets and pull the spring off revealing the valve seals which you can replace without removing the head. Obviously, the cylinder that you are working on should be at TDC of the compression stroke to make sure all valves are closed. You also may have to jam the crankshaft in that position so that your pistons don’t move. Once you have done one you should get the idea and it becomes easier.

If the motor hasn’t been subject to any abuse like being excessively overheated it’ll probably be ok. You could skim it if need be as there’s a fair bit of leeway in the backlash taken up by the crank and cam scissor gears.

Thanks for your advice Don

I am still working through the valve guide oil seal replacement. Rear head done and all valves, springs etc in spec so very good.

I removed the front head this morning and the two cylinders had coolant in them, a reasonable amount too (50, maybe 70ml??) …it started to leak out the head gasket as I loosened the head bolts.
Question: is this normal OR do I have a problem?

Note: Before strip down the engine was running ok, the spark plugs looked a good colour and there was no oil in the coolant when I drained it so I am thinking it must be the angle of the head and water draining out of the head when I loosened it and because the head gasket was loose the water could move between water holes and bores… but would welcome your opinions please.

Sounds like it’s just run into the bores as you took the head off,nothing to worry about

Yes I think you are correct, I have cleaned it all out now & removed old gasket.
No water in the engine oil below the cylinder so just leaked from waterways when the head was removed.
There still seems to be water sloshing about in the water jacket.
Thanks for re assurance on this one.

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