To remove the camshafts, or not to remove the camshafts...

So. XJ650H that I bought. Was the PO's first bike. He changed the oil and filter religiously, supposedly, during the 4 years/10k miles he had it. He knew nothing, however, about valve shims. So those had never been touched.

Popped the top off (20 bolts! Yowza! And I thought the 12 on the '82 was bad!), and the gasket has been hell. The clearances weren't terrible--one loose exhaust (.22) and two tight intake (both .09)--but the gasket... Spent a day and a half going at it slow and steady with a razor. It was mostly stuck, unfortunately, to the engine, and not to the cover.

My first question is a small jump: on the right side of the engine, there seem to be two rubber half circles? The '82 gasket has these rubber half circles that hang over the edge (which I always thought was odd--orientation?), but the '81 gasket is just a thin paper thing. I started trying to cut the rubber half circles out, but now it seems like there's no metal there underneath--like the rubber half circles are part of the head itself. I'm afraid to cut more. Am I missing something, or imagining something? Do I need to put pictures?

Second thing is that, in spite of my best efforts, 8 hours or so of cutting off gaskets has let lots of little flakes of old gasket get into the gallery. I imagine I should get this stuff out before running the engine again.

Only that's a bit of a pain. So, how to do this?

Plan A: Remove the camshafts (haven't yet done this before), and sop everything up with a rag. Then spray compressed air. Then sop up some more. Then fill a little with oil. Reassemble.

Only, from what I'm looking at, pulling the camshafts isn't as easy as I thought--I'm kind of afraid of screwing up the timing.

Plan B: Use clear tubes to drain as much oil as possible. Then jam rags underneath the cams and around the camshafts as best I can, for some time, really sponging and wiping it all out. Then use compressed air. Then refill oil. Camshafts stay in place.

Which is the better course of action? How terrible would these little gasket flakes be, how hard will this be to remove, and how hard are these camshafts to take out and put back into place?

God, this has been the gasket from hell. Oh yeah, how 'off' does it need to be? I feel like there's so little left, but I can't get it all--like I gouge as much metal as I scrape off gasket at this point. I can almost not tell the difference between it and my finger if I slide it over with my eyes closed. Is that ok for a little to remain?

 

For the gasket, and half moons. You already know the source. Just drop a line to Chacal.

As for the cleanup. I would lean more towards plan B. No sense in risking contamination of the cam bearing surfaces. Just make sure you clean the shim, and cam lobe surfaces completely before firing the engine again.

You can use an emery board to clean up the last remaining bits of gasket. try not gouging the soft aluminum of the head or cover as this will lead to oil leaks.

Ghost

 

Nobody owns a SHOP VAC? I'd vacuum the bits out, oil and all. Next time shove a couple of shop towels in there BEFORE scraping gaskets.

I's important to remove the old gasket; and it's equally important to NOT chew up the gasket surface in the process.

I would recommend a couple of cheap plastic paint scrapers from the hardware store; along with some careful use of lacquer thinner or gasket remover. My own personal favorite mini-gasket scraper is a dull chisel-blade X-acto knife, but it requires careful technique to not gouge up the gasket surfaces.

As you've discovered, the rubber half-moons are separate pieces on the non-YICS motor with its lovely composite gasket. Fun, huh?

 

Wow. I already had a spare gasket, because the first time I ordered a gasket for my '82, a seller's mistake had me sent an '81 instead. But I have to order the half moons separately? That's a bummer. (MiGhost--I was asking for a supply source, I was asking how they worked.)

I was thinking a shop vac, but no, I don't know anyone who has one. Maybe I could rent one?

I don't think you guys realize how badly this gasket was stuck on there. Full brand new razor blades were not getting it. Plastic wouldn't even BEGIN to scrape anything but the easiest parts of the job.

I haven't damaged the mating surface seriously, but there are tiny little cuts. I have some very fine sandpaper I've been using for the last stage that buffs those little nicks right out.

 

Great answer FItz.Just a warning,DO NOT ever,ever use a shop vac for anything flammable!Being in pump & tank over 13 years I saw too many gas station dealers too cheap to pay for water removal go BOOM.

 

Anything flammable... like oil? xD

 

Just checked; gas is a definite no-no, but oil is fine.

 

Oh! Ask and you shall receive! I do know someone with a shop vac! Life is better. *sigh of relief*

 

Just for future notice, in case anyone searches for this:

Shop vac kind of worked, but only sort of: had trouble getting under the camshafts, suction didn't reach that far. Compressed air on one side and shop vac on the other, though, worked ok. That, plus rags, and then clean oil, seemed to work lovely.

I got the last gasket off quite thoroughly with careful application of a razor blade and some use of fine sandepaper block afterwards seemed to clean up the very small knicks. I haven't seen any leak in the 800 miles since, and believe I'm fine.