How do you remove stuck exhaust valves? KIPS

[Bigtim]

I'm doing a top end on a 98 kx500 and the exhaust valves are so gummed up i cant remove them.  I've spray a whole can of carb cleaner on the prts i can access thru the exhaust port and bottom of the cylinder.  I heard of using oven cleaner but it say not to use on aluminum on the label.  Im on the verge of using a slide hammer... what does anyone think of hosing it down w/ pb blaster?  I've already tried wd-40, fluid flim, BR 6 in 1, and some gentle heat.  Oh ya another option I 'm kind of nervous to try is submerging the whole cylinder in that carb gunk remover stuff, majorlly caustic stuff!  The valves are stuck closed and the action shaft(top end one) is moving freely.  surfs up! BT

[stewart]

i buy a cheap 5 gallon pale off  lacqour  thinner leave in  over night

[Bigtim]

I GOT IT OUT!!!!   I ended up using the slide hammer.  I didn't get to stu's idea yet( didn't have to)  I left the jug in the parts washer a while ( Whats the diff. btwn solvents and something like laquer thiner?)  The actual valve drums were not the problem, the can of carb cleaner took care of that goo, one of the drum collars, was chuffed up on installation, not me but the guy I bought it from or his mechanic.  So i (we) drilled a 6mm tap into the 10 buck collar, put a bolt in there for hammer tip purchase, and let her rip.  The valve actually came right out with the destroyed collar.  Everything was very gooed up and inop.  Soak all the components in the parts washer, snad blast those babys new again, orderup some o-rings, seals, and now an alumininum collar.  Reassemble, badda bing...  I saw some interesting posts about advancing the KIPS timing, I'm gonna try that too. I can't wait to fire this little puppy up.

[don46]

oven cleaner works pretty good on the carbon'd parts