1982 XJ750 Cam timing pictures?

I'm getting ready to put my cam shafts and chain back together and I don't have a service manual. I was wondering if anyone could post some pic's of TDC and the cam shaft markings so I can be sure I am lining these things up correctly? I searched the forums but didn't see anything with pic's but I could have missed it. So maybe just a link would work.

Thanks in advance!

Tom

 

ok. these pics are of my 600 engine not 750 ,but the principle should be the same, heres a pic of the shafts at tdc.
look closely at the middle of the camshaft retaining caps, down at the cam flange you can see a dot on the cap , and a corresponding dot on the camshaft. they're lined up at tdc

hope this helps.
stu

 

You should get a manual. Procedure involves rotating the crank at the ignition pick-up then use of a wrench on the cam shaft nut to align the dot. Stu's pic will be the result.

Gary H.

 

I did find another posting on this forum with quit a bit of info. Can you tell by this pic if I'm lined up at Tdc?

 

That's not the timing pointer. The timing pointer should be to the right. That's a firing pin. It will fire 1 and 4 or 2 and 3 when the center plate spins. @TDC the T will align with the pointer and the cam shaft dots will be on the top. Cylinders 1 and 4 will be at the very top of the compression stroke. Make sense? Hope this help.

Gary H.

 

While you'll find a lot of info on here, I still wouldn't attempt to time cams in without a manual. The results of screwing up can be catastrophic. I haven't done my Yam yet but the Kawasaki KZ procedure is pretty detailed and has a couple ways to verify. Kaws you have to pull the cams to change shims.

 

I agree with jay. If you don't do this right you'll ruin a good mill.

Gary H.

 

Agreed. I kind of only get one shot at this. I might post some pics after I get it set just to get everyone's blessing. Great forum., Thanks!

 

Fwiw you can get it right but you can't guess or hope it right. Proper procedure will put it spot on and give you knowlege/experience for future endeavors which might include doing this again. The cost of getting it right far exceed guessing and getting it wrong.

Gary H.

 

this is not right. here is the timing marks showing the advance point for ignition timing. the "t" should line up with the center of the stationary pointer.



FU

 

Again, the came dots must be on top or you'll have cylinders 2 and 3 @TDC. The cam dots tell you cylinders 1 and 4 are @TDC. And again, you should get a manual. Hope this help.

Gary H.

 

he already has the cams out, so having them at the right place does nothing for the crank.

FU

 

I'd like to help Tom without possibly confusing or mis-leading him. The procedure for doing this is not difficult but must be done correctly.
I digress.

Gary H.

 

i wouldn't use that "stationary" pointer. these bikes are 30 years old and that pointer isn't very stout. the paint on the screw doesn't mean anything it the pointer gets bent.
at least check it with a McDonalds straw in the plug hole.

 

I agree, you cannot rely on the stationary pointer being accurate.

FU

 

yes. to the op, if you removed the cams without setting the engine to tdc for #1 cylinder before disassembly. then you should put the crank on tdc (see my post above) before you reinstall the cams. then the cams should go in according to the pics rocs posted above. if you roll the crank with the cams in and the chain off, you will bend valves and you will have to remove the head to replace said bent valves.

FU

 

here's your pages
http://imgur.com/a/Z3GgH

 

All of us were trying to help. However, this is what Tom needs.

Gary H.

 

Oh, wow... Thanks. Let me study this a bit.

 

that's just 3 pages of the book, everyone should have a book

 

Or three, since none of the service manuals cover everything clearly, and all three publishers refuse to revise the errors that each has.

 

Ok I really thing I have it. Take a look. The thing that was sort of weird was that the cam claim arrows point away from the dots on the cam shaft. Trust me, I put them back on exactly the way they can off. I have done two complete rotations and it lined back up.

 

The arrows that are cast into the upper cam bearing journals are there to indicate the correct orientation of the journal. They have nothing to do with setting cam timing. The timing marks will be either a small arrow tip cast into the journal, or a mark machined onto the outer vertical face of the journal.

Unless your timing pointer was bent you do not have the #1 Cylinder at TDC. The pointer should line up with the T on the ignition plate. Yours is lined up with an ignition firing mark. This means that your cam timing is off.

Have you confirmed that #1 is at TDC using a reliable refence, such as a dial caliper, or at the very least a dowell that you put reasonably accurate reference marks on?

 

Yep. Both are at the top.

 

looking at the pictures, the tdc pointer isn't quite there yet and the cam marks aren't quite there yet either. one little bump and everything should line up.
the pointer screw obviously has been messed with, i'd make the cam marks dead on then bend the pointer to line up with the "T" mark and your good to go

 

I realized that to. I had it spun just a hair off when I took the pic but your right if you look at the pointer you can tell it's been messed with. One thing I didn't mention was I didn't unseat the sprockets from the chain. I loosened the sprockets from the cams and lifted the cam shafts up enough to replace the shims but didn't take them out. So, having not taken the sprockets off and matching the marks up at Tdc. I think, I should be right back where I started.

 

Can't "think" on this one Tom, you must know for certain that #1 is @TDC. It's critical. Hope this help.

Gary H.

 

Polock is right.... Try to get a manual. So much good info. It is well worth it. You wont regret it. Message me if you need one.

 

Guys BIG thanks! I tried to post a video of me starting her up but I guess it's the wrong format. I was a little nervous but I took my time and went over all of your post a few times. This was the first time she started cold without starting fluid and a lot coaxing. Sounds strong and smooth! Balancing the carbs are next and my yamaha dealer loaned me the tool. Anyway, thanks to the group. I've been a member of the FZ1OA for years and this forum certainly rivals that one.

Thanks again!

Tom

 

Just because I thought it was a fluk I started it again this morning... cold. Bang first spin and it's going. Now, I did re-clean the carbs and my enrichment reservoirs and 3 of the 4 carb bowls were clogged so that may have had something to do with it but I have never seen this dramatic of a change in a bikes attitude. So, I guess for all those hard starting guys I would certainly recommend valves & check those carb bowls. Thanks again! Hopefully I'll be able to help someone else.

 

I know this is an old post, but would like to include the participants.

I am ready to do my cams... I am posting the manual page, my CAM Top view and Crank TDC. Also, you will notice a photo of a mark I placed during the Tear down, it does not corrispond with the mark on the CAM.. now I am very concerned. Should I follow the CAM Mark or My Mark.. they are 180 degrees apart.?

 

Son of B... I wonder if when I tore it down, I had the C aligned with the TDC Tag, and my cams may have been roatated 180 Degrees... Can someone verify if the CAMs rotate 180 when at the C mark??

Also, The CAMs aligned at the Top with the CAM Mark seem to be dead on, and no pressure to the valves, so is it safe to say that all valves are Closed at TDC ?

 

no they do not. t mark is only a little way from c mark 180 degrees would be on the other side of the disc. the disc is on the end of crank shaft

 

Tom was last seen:Feb 3, 2015

jmilliken was last seenec 22, 2016


start your own thread would be better for you


rocs82650 was here saterday and polock too

 

yes go by the marks on cam shaft and cam shaft cap for proper alinment just as the book shows you.
did you mark intake shaft and exhaust shaft as shuch?

 

here is the new thread.
https://www.xjbikes.com/forums/threads/xj750-cam-timing.120686/