Valve seals

[tw1980]

Well I'm getting things back together.I was getting ready to drop my cam gears off at the machine shop to get them slotted when I decided to give the gears I got from Mega Cycle one more try.A couple minutes with the dremel tool and wallah!They fit!Now I have adjustable cam gears.
Terry

[XS1100 Newbie]

Terry
You wouldn't be building a hot rod would you? LOL

[fredintoon]

Well I've got a leaky valve seal in no 1.Has anyone tried pulling the cams and replacing the valve seals without pulling the head?I thought I could pressurise the cylinder and change the seals like we do on cars. Terry

Hi Terry,
if you really want to do this, here's a way.
Pull the sparkplug. Feed in a length of rope. Leave a foot or so hanging out.
Crank the engine by hand to bring the piston up to compress the rope to hold the valve tight against the head.
Pull the camshaft. Remove the valve bucket.
Use an automotive style spring compressor to remove the springs. Swap the seal.
Put it all back together. Pull the rope out.

[petejw]

Fred,
sounds good, but id remove the camshafts first otherwise
the valves will bend.

[fredintoon]

Fred,
sounds good, but id remove the camshafts first otherwise
the valves will bend.

Hi petejw,
I should have been more precise.
"back it up on the compression stroke"
But of course you are right. Pulling the cams first lets you do the ol' rope trick regardless of what stroke the engine is on.
However, it's a daft idea anyway, especially on an air cooled motor where there's no worries about loosing coolant.
But he did ask.
How much extra effort is there to pull the head and kiss the valves in once you've pulled the cams?

[tw1980]

Terry
You wouldn't be building a hot rod would you? LOL

It's already built I'm just adding adjustable timing cam gears.My cams are tuned to give more high rpm performance,I'm hoping to be able to fine tune things a bit. Terry

[tw1980]

Hi Terry,
if you really want to do this, here's a way.
Pull the sparkplug. Feed in a length of rope. Leave a foot or so hanging out.
Crank the engine by hand to bring the piston up to compress the rope to hold the valve tight against the head.
Pull the camshaft. Remove the valve bucket.
Use an automotive style spring compressor to remove the springs. Swap the seal.
Put it all back together. Pull the rope out.

Good idea Fred but I couldn't figure out a way to compress the valve springs with the head on.I rigged up an air pressure fitting and pressurized the cylinder but couldn't make it work.If I was a better machinist I probably could have fabed a special tool and then have Geezer market it for me but I'm not that good. Terry

[3Phase]

If I was a better machinist I probably could have fabed a special tool and then have Geezer market it for me but I'm not that good.

It'd be difficult to make anything that would work on just the valve spring and keepers without bending the valve face in the head. The valves are kind of fragile and you'd probably end up pulling the head and replacing some bent valves too, not just the seals. DAMHIK....


Regards,

Scott (Full XS Moron)

[randy]

If your valve seals are that shot, chances are the valve stems and chamber are gunked up, and the seats need lapping at least. Chain may also be tired. I agree with previous posts, a few more bolts and the head is off. Do it once.

[tw1980]

If your valve seals are that shot, chances are the valve stems and chamber are gunked up, and the seats need lapping at least. Chain may also be tired. I agree with previous posts, a few more bolts and the head is off. Do it once.

Actually the valve seals are fairly new.I replaced them when I installed the big bore kit and cams two years ago.I messed up no 1 exhaust valve seal when I installed it. Terry

[petejw]

Hey Terry,

I think 1 of the aussie guys made something up
that could compress the valve spring whilst the head was fitted
to the engine but i couldnt find it on here.

Would be a pity to have to pull the head
off for 1 valve.

[petejw]

found it,
was Steptoe
heres a link he posted

http://steptoexs11.webs.com/apps/pho...otoid=35979444


heres the post he posted on here

http://www.xs11.com/forum/showthread...ing+compressor

[TheFrugalTech]

The only chemical solution to cleaning carbon I have found to work well and safely is PB Blaster. Helped a buddy with his using it.
Spray it down enough to soak into the carbon and let sit overnight. The carbon won't fall off but should clean easily with a very stiff nylon brush. For any flat surfaces including the piston tops, or any other spots you need to scrape a bit, use a good quality plastic putty knife. It will be hard enough to scrape the carbon off but not scratch any metal. "Lather, rinse, repeat" depending on how much carbon your dealing with. Took us 2 applications and everything was really clean. Something to do while you are working on other things.
I have heard of using various oven cleaners but never tried any myself. Be careful what you use and know your basic chemistry, wouldn't want the head eaten alive from the inside out.

[fredintoon]

found it,
was Steptoe
heres a link he posted

http://steptoexs11.webs.com/apps/pho...otoid=35979444

Hi Petejw,
nah, that one needs the head to come off before it can work.
The automotive style valve tool is held down onto the rocker studs or similar so it can work from the top without pulling the head.
The ol' rope trick is for folks who don't have a massive high pressure air supply to hold the valve shut.
Leaving a water-cooled straight 6 head in place to renew valve stem seals makes economic sense especially if you are paying a mechanic to do the job.
The same argument don't fly for DIY on an air-cooled 4.
As my post said, "If you gotta do it, there is a way."

[tw1980]

Well she's all back together.Carbon removed,valve seal,battery,new slotted cam gears and new exhaust.I ran a cold compression test just for kicks and got 155 in 1,2,3 and 160 in 4.I put about 3 to 4 deg advance on the intake cam and left the exhaust stock.On the advise of Big Daddy.He has about the same mods I do and he sprung for a dyno.She starts and runs good.It may just be my imagination but I swear I can hear way more cam at idle and even with a new battery I can hear it hit harder and turn slower when cranking.Can this small adjustment with the modified cams make that much difference?I didn't test drive tonight it was cold,dark and I was drinking beer while working on the bike.Hopefully it will be nice enough for a test drive tomorrow. Terry