revs drop-update: faulty valve seals ( I think!)

Hi community. I took the motor apart so I could look at the valve seals after discovering oil on cylinder 1 and 2's spark plugs. The bike was idling very erratically and I couldn't ride it anymore. My problem: how to compress the valve springs so I can change the seals, clean the valves and lap the valves and seat ( good idea?) I've looked
at a small engine spring compressor but it only worked on exposed springs. Please help.
Thanks

 

Did you pull the head? If not pull the cams out , autozone or sears used to have a bung that threads into the spark plug hole. Bring it to top dead center you need an aircompressor. About 30 psi they sell a spring compresser for this it pushes spring plate down as you can remove keepers out and pull spring and you can then get at seal.

 

are you sure it is just the valve stem seals and not worn valve guides too? if your going to do the valves it would be a good time to check the valve guides.

you should start with a COMPRESSION test as outlined in
The Information Overload Hour

read this after test Now Analyze This!: it is below the specs

 

Before you go tearing into things....do a leakdown test. Unless you already have. (this is why one thread per bike is helpful).

 

Yes I did pull the head. The way the first 2 spark plugs were covered in oil explained the misfires. I saw a thread where a guy uses a 6'' C clamp to release the keepers. Works? Because tomorrow I was planning on getting one to finally access the valves. My engine is a 1982 seca 750 with 56 000 km ( roughly 35 000 miles). The seals rubber has probably dried out.

 

I didn't know about that. I thought the only way was to pull the head ( and the headers, and the carb and the...)

 

Or use rope to fill the combustion chamber, and a socket to compress the spring (the socket needs to be cut to fit the keepers back in though.

 

Oxygen sensor socket has cutout, those work for that

 

Or the correct tool