Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature currently requires accessing the site using the built-in Safari browser.
We noticed you are blocking ads. DO THE TON only works with community supporters. Most are active members of the site with small businesses. Please consider disabling your ad blocking tool and checking out the businesses that help keep our site up and free.
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
Are the wear marks on sides of cylinder/gasket?
Can the cam 'float' in head?
most (but not all) have a thrust washer on right end of cam to move it slightly left and keep chain centered in tunnel
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
Sonreir said:
LearnAsIGo! - The color is called "Gold Rush Metallic" and the code is 7270830 but is sometimes shown as just the 7270 portion. Rustoleum is the brand.
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
Here's the areas of concern. The copper gasket did look a bit worse, but I gave it a couple of taps with a hammer to smooth out the area that had been eaten up.
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
Yep, looks like the sides of tunnel.
Check cam movement in head, thrust washer is probably missing.
Don't need to fit head on motor, just fit sprocket and check chain line is centered in tunnel.
Check crank sprocket is centered inline with cylinder tunnel
It isn't possible for the chain to hit front and back area's, did you check before assembly?
You usually find that type of wear only happens with a broken tensioner/guide
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
Sorry... I forgot to mention that I ended up replacing the existing the thrust washer with a slightly thicker one I had to order from CMSNL. During the teardown I found the side-to-side play in the cam to be out of spec and so a thicker thrust washer was necessary. I'll recheck everything again when the head gets back from the machinist.
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
Just a little more clarification... The chain only seems to be contacting the front/exhaust side. No abnormal wear on the tensioner side of things. Both pics shown above are the front of the cylinder jugs, they're just taken from different angles.
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
The guide won't allow chain to hit cylinder at front, it can only hit at sides.
Are there matching marks on back guide where it's been contacting cylinder/gasket?
Really, the guide can only hammer on cylinder if chain is loose (worse at low rpm as cam tries to turn crank when valves close)
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
I'll have to look the guide over again once I get home, but I don't recall seeing or feeling anything abnormal. Seeing as how I'm running stiffer valve springs, is it possible that the springs are turning the cam rather than the crank turning it? Or does the tensioner prevent that as well?
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
I was thinking it could possibly be an issue?
It would be worse at low rpm/idle as there is more time for load reversal
I guess the only thing you can do is run at high rpm or fit stock cam/valve springs as I haven't figured out any sort of replacement tensioner blade (too much other stuff going on )
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
Sonreir-
Ive been off the board for a few weeks and just caught up the last 5 pages!
Just wanted to let ya know there are plenty of us following the thread and although we cant be as helpful as good ol' PJ we are here to support ya!
I am sure you will have her back on the road in no time, these bikes are some of the worst and best machines I have ever worked/ridden.
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
I've been communicating with trek97, are you setting cam chain tensioner 'by the book'?
'the book' doesn't give you all the information you need.
Crank has to be turned and held in position with a socket/spanner/wrench.
I use a 14mm combination wrench and let it jamb against footrest as cam is trying to turn crank backwards (pulling front run of chain tight)
If your just loosening and tightening adjuster, it won't be tensioned properly (except by luck)
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
crazypj said:
I've been communicating with trek97, are you setting cam chain tensioner 'by the book'?
'the book' doesn't give you all the information you need.
Crank has to be turned and held in position with a socket/spanner/wrench.
I use a 14mm combination wrench and let it jamb against footrest as cam is trying to turn crank backwards (pulling front run of chain tight)
If your just loosening and tightening adjuster, it won't be tensioned properly (except by luck)
That's probably what I'm experiencing. I'll give that a go.
Also... frogman mentioned that it's maybe not my chain at all. I'm told that the marks I'm seeing may just be from contact with the back of the guide. Marks on the back of the guide seem to coincide with the marks on the gasket and cylinder jugs.
Finally, should I expect to see any wear on the chain if it were rubbing or is the chain hard enough to not show any damage from that sort of contact?
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
The new valves should arrive in the mail today. Pics up once they get here.
Also... there's a been a slight delay on the upholstery as my Mrs wants to do it and she keeps her own schedule on these kind of projects. I may have to find a way to provide some incentive.
In the mean time, I "safety wired" the headlight to make sure it didn't spill out onto the road while I was riding (thanks for the suggestion, Swagger!). I'll be touching up the paint on the frame while I wait for upholstery and head work.
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
Yessir... Valves were $195 after including the costs of shipping. New bronze valve guides were about $70 and there's going to be machining costs as well...
Going fast sure isn't cheap. I'm very much considering saving a few bucks for a dyno run so I can quantify all of this.
Re: '77 CJ360T (Café SOS) - Head and Valve Work in Progress - Expensive Mistake
If you 'do' dyno, make sure they connect up the EGA, you need to know what fuel is doing
Hopefully, you should be getting around 42~45bhp with the mods you've done
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.