Long overdue update

[Eastcoaster]

valves

Mike
I am with ya I think might have bent the valves He has nothing on the compression I asked him to check the valve clearances. and also see if he can verify if they are stuck maybe look in the ports? This head had 6000 miles and ran good its been off a year so I cant imagine corrosion would hold all the valves it was inside.
Waiting to see him post and see where he is he worked all through the night I hope he did not miss something in the timing He is a good enthusiastic young member we will get him through this If you have any thoughts on what to do before he removes the head please advise
Thanks

[CaptonZap]

http://engineersedge.com/power_trans...sion_check.htm

CZ

[Ranger_xs1100]

compression leak tool

The original problem was no compression and now you still have no compression with a replacement head. You turned the engine over with the kick starter before trying the electric start. I would think that if the valves were hitting, you would have noticed that when turning over with the kicker. That makes me wonder if the no compression condition may not be a valve problem at all.

Here is a cheap and quick way to test where the compression leak is:



Take an old spark plug and break out the ceramic. insert a rubber air valve stem into the hollowed out plug.
screw the plug into each cylinder (one cylinder at a time) that is set to TDC on the compression stroke ( both valves closed). Attach air compressor like you were putting air into a tire. Then just listen. You'll hear air leaking out of the front , back, or bottom of the engine.

front = exhaust valve leak
back = intake valve leak
bottom = rings leaking

I know its a crude setup and I'm sure there are better ways, but it worked for me!

[Bonz]

The picture in post number one, with the head sitting upside down and the valves facing up. Do the valves sit off the combustion chamber face like that? Or should they recess back in there more flush?

Have you had the valves out of the original head to see if they are bent?

I haven't done cam work on the XS, but on my ZRX it's real easy to get it out of time by a tooth and not realize it. The ZRX has enough room that a tooth one way or the other is not going to hurt anything. Not sure on the XS? And is it different for the early heads versus the later heads?

[Eastcoaster]

Tdc

Talking to Seth It appears he has timing and cams lined up and will post pix they might be off a hair. The question I am thinking I always verify number 1 cylinder is TDC
Is it possible the pointer could be on T and due to the rotation the number one cylinder is not on top??

[Bonz]

The "T" is a direct line to the crank and thus piston position. Should always give TDC on #1 cyl by my estimation. Don't know how something could "slip" and make it be otherwise.

Question: Can the XS be a tooth or two off on the cams and not bash valves?

[sethhope]

I verified tdc on #1. As for everything else, here's a few pics of the timing.

[3Phase]

I verified tdc on #1. As for everything else, here's a few pics of the timing.
[...]

Are the camshafts in the correct location with the Exhaust cam in the front of the head, Intake in the rear?

No, it is not possible for the timing pointer to remain on the T mark if the piston moves. If the piston moves then the crankshaft rotates and so does the timing plate.

It is possible for the crankshaft to rotate if you don't find a way to hold it in place while you install the camshafts, gears and chain. That can bend a valve in one cylinder but if the timing marks stay even close to correct while you work then that wouldn't kill compression in every cylinder.

[sethhope]

The cams are correctly placed

[Eastcoaster]

at this point

Seth at this point I think we have exhausted all resources and the head has to come off. I am thinking this is best. I would take all the valves out of both heads and check everything. I know the head I had they were Ok they came from a running bike that was wrecked last year I am hoping its varnish and gum holding them open from sitting going this far I would change the valve seals they are cheap and good protection from oil burn also lap the valves if good. I have one I am doing on my 79 now If you get it off and want to do it here or if you want my tools let me know be careful to keep everything in order most of all the valve shims from each valve mixing up is a nightmare to get them dialed in.

Let me know if you need help

[3Phase]

The cams are correctly placed

I don't suppose the camshafts were ever installed in the head on the bench and anyone tried to turn or position the cams before putting the head on the engine?

T.C. has said that he did that on his first XS1100 engine and doing that bent almost every valve in the head before he very carefully put it on the engine and set the timing, then found out there was no compression.

[Eastcoaster]

one more question

One last basic question
Have you verified the engine is in rotation when you hit the starter?

[Bonz]

How does mounting the cams on the bench bend valves? It may push a few open a tad however if it's on a surface (towel, shop rags) with some give should not be any issue?

Bench mounted the cams and checked valve clearances after removing and cleaning all the valves and cleaning up the head while installing higher compression pistons the other day on the ZRX 1200. Takes a bit more time with 16 valves. LOL. And much more of a pain keeping track of where each valve belongs throughout the process.

And yes, could have broken something in the starter system with the back fire? Would give the appearance of compression when turning by hand but nothing when pushing the button.

[IanDMacDonald]

I remember T.C. telling me the story when I bent my intake valves. From what I remember, he had it flat on the benchtop, and a few were open. Bent the stems.

[3Phase]

I remember T.C. telling me the story when I bent my intake valves. From what I remember, he had it flat on the benchtop, and a few were open. Bent the stems.

Hitting the bench and I can't remember but some of the valves may have hit one another when the cams were turned out of time with each other and two valves were opened in the same cylinder.

I know I came -->.<-- that close to doing it myself when I was goofing around with clay to check clearances with different year heads and pistons.