Need to change Valve stem seal(s)

[Mooskee]

I have symptoms of at least 1 leaking valve stem oil seal. I have reviewed the Honda Service manual and the Clymer manual. Each require removal of the head for replacement of the seal. I don't have a problem with removing the heads but I would like to replace the seal with the head on.

I have reviewed the forum for threads on the subject. There appear to be some good ones, but the critical associated pictures are no longer viewable.

All that to say, I would like some input from some of you who have changed a valve seal without removing the head.

How are you holding the valves in place so they do not fall in?
Are you rotating the cylinder to TDC?
Are you using air pressure to hold the valves?
What valve spring compressor works?
Are there any problems with rotating the engine with the cams removed?
What am I missing?

TIA

[sandy]

An old mechanic trick is to force a pipe cleaner into the plug hole till the cylinder is full. This holds the valve up.

[Mooskee]

.quote author=sandy link=topic=119469.msg1213679#msg1213679 date=1634785454]
An old mechanic trick is to force a pipe cleaner into the plug hole till the cylinder is full. This holds the valve up.
[/quote]


I've heard of using rope.

[da prez]

Air pressure.

      da prez

[John Schmidt]

I made my own air injector using an old spark plug and knocking out the ceramic center portion. I then sealed a short piece of pipe into the gutted spark plug with JBWeld, the pipe is about 4" long and threaded on both ends but only needed on one end to attach the air line fitting. The entire thing is only about 7" long and worked well on a number of occasions. I've used it a number of times replacing seals on old 4 cylinder Gold Wing motors that happened to have fairly low miles but sat unused for many years. When used, I just roll the cylinder to be worked on up to TDC, inject low pressure(doesn't take much), then go about compressing the spring(s) with the other tool just enough to remove the keepers. I found it a bother to have the air injector hose left in place while removing the valve springs so found a cut off valve I could put on the air line hose end of the tool before attaching the injector. That way I was able to fill the cylinder with air and remove the hose. The picture is from before I replaced that connection with the cut off valve...I looked but apparently never took a picture of the tool with that conversion.

[Bagger John - #3785]

If there's one leaking, there will eventually be more leaking.

Pull the head and replace them all.

[Mooskee]

Thank you John, and da prez. That is about what I figured with the air pressure.
I may go with this method for an immediate fix.

Bagger John, I did buy 12 new seals. I will replace them all, I just may go for the immediate fix for the one that is leaking now. Still debating pulling the heads. I wonder if in the long run it is easier and faster to just dive in and pull both heads and do them all at once.

Thank you all for the help.

Dave (mooskee)

[Bagger John - #3785]

Thank you John, and da prez. That is about what I figured with the air pressure.
I may go with this method for an immediate fix.

Bagger John, I did buy 12 new seals. I will replace them all, I just may go for the immediate fix for the one that is leaking now. Still debating pulling the heads. I wonder if in the long run it is easier and faster to just dive in and pull both heads and do them all at once.

Thank you all for the help.

Dave (mooskee)

Dave,

How many miles on the bike?

I'd check the guides while everything is apart too.

[Mooskee]

John,

76, 039 miles.

I have started making plans to pull both heads and change all the seals. I will check tolerances while I have it apart anyway.

It is extra time and money, but it will be one and done. I have rounded up head gaskets and seals, and am going to go through the manual and see what  else I may need tonight.

[Rio Wil]

Just out of curiosity, what symptoms are you seeing.......76K is no mileage at all for these engines...

[CoreyP]

I did this a couple of months ago on a truck. Leaving the heads on is much easier and there is no real reason to make the job harder on your self. Compressed works well.

[Mooskee]

Just out of curiosity, what symptoms are you seeing.......76K is no mileage at all for these engines...

I've got a lot of oil loss coming out rt side exhaust. At first I thought it would just be valve stem seals, now I'm  wondering if I havve a blown head gasket. I need to run compression checks.