oil leak on front cylinder exhaust

darren nix · Post by **darren nix** » Sun Jun 18, 2006 2:01 am

hi out there, have a 1981 MHR that i have acquired, trying to get it sorted as it was sitting for four years,went to get a roadworthy and when i returned home i,ve noticed oil trailing out of the front exhaust , with no workshop manual available what am i looking for, a damaged valve or seat or guide etc. thanks for your help

Geoff · Post by **Geoff** » Sun Jun 25, 2006 12:53 pm

I had something similar on my rear and it was either of the guide seals or the bore; I changed the seals and the rings and deglaze honed the bore and I was fine; see further down in my posting http://www.bevelheaven.com/~BB/phpBB2/v ... highlight=.

Otherwise some others have had similar problems with more esoteric solucitons; check this http://www.bevelheaven.com/~BB/phpBB2/v ... highlight=

Cheers
Geoff

darren nix · Post by **darren nix** » Mon Jun 26, 2006 2:53 am

thanks for your reply Geoff. i visited the section where you helped Magnus with his darmah and followed your instructions, i was missing an exhaust valve seal completely and the inlet valve seal was split, the head is back together but not on the bike yet, what i would like to no further is, if everything was put back together as before, can i assume that if the the timing marks line up that it has been put back as should, its hard to no while i am waiting for my workshop manual to arrive regards darren.

Geoff · Post by **Geoff** » Mon Jun 26, 2006 1:02 pm

Good work Darren; I've been on vacation hence the tardy reply to your first post.

You'll find manuals on Steve's site here. But if you set the timing marks up on the heads before you stripped and didn't move the engine (and reset the timing marks back on the head you removed) then yes it should slip right back on. That Pete Shearman ref in the Magnus post is also good for timing.
Cheers
Geoff

darren nix · Post by **darren nix** » Mon Jun 26, 2006 1:53 pm

thanks Geoff, when i put it back together this weekend i will let you no how it,s gone

darren nix · Post by **darren nix** » Sat Jul 15, 2006 2:30 am

back from holiday and all the parts i ordered are here now, it seems the more i inspected the worse it got, i have two questions, the middle ring for the front piston isnt stamped top and i can not remember it,s position, does the thicker or thinner part of the ring go towards the top of the piston my manual says it should be stamped top but neither old or new ring are stamped. Second question , how much play left to right should there be on the con rod if any! regards darren

Geoff · Post by **Geoff** » Sun Jul 16, 2006 4:35 pm

Away for the weekend myself. The original rings do have TOP marked on them, but can get a bit tarnished. Perhaps new ones don't, I can't remember.

I didn't remember the ring order but fortunately have my old set still bound in the correct order; upper ring has the cut out edge to the top and inside (piston side) while the second ring has the cut out to the bottom and to the outside (bore side). I've put a couple of photos below but not sure if they too clear (hard to take such close ups):

The square case con rod side to side play is give on the supplement to 860GT-GTS workshop manual (on bevelheaven I think). Pages 68/69 and quoted as 0.430 to 0.914mm new, 1.2mm wear limit. The thrust washers either side of the con rods are known to fail.....but don't get too carried away. Some machine shops now actually attach proper shims ot the webs and machine them down to size!

Use the info with care.
Cheers
Geoff

darren nix · Post by **darren nix** » Sun Jul 16, 2006 8:45 pm

your a wealth of information, once again many thanks Geoff, i will tell you the result, regards darren.

darren nix · Post by **darren nix** » Mon Jul 31, 2006 11:15 pm

the bike got put back together a week ago, getting the barrel over the rings was the most frustrating part of the whole exercise. The pleasing part was it fired up first go, today i have run around and got the roadworthy done and the rego done,got about 85 km under its belt.Set the carbs up last night and it seemed to be running nicely [set by ear] from what it was , but on the road its running like a pig so thats the next job. any way , for the computer dumb , how can i post my picture ive read the gallery post, but am still a little confused, regards to all who helped

Geoff · Post by **Geoff** » Sat Aug 05, 2006 4:56 pm

great work darrne; you'll need a few km to get things bedded down, then set her up good 'n proper; with proper carb sticks of carbtunes or whatever; real easy. Steve has a pretty good go-by on his site somewhere.

Pic posting requires that you save the picture somewhere else first, then reference the picture in your posting here. I use xs.to just type in xs.to in the browser address bar and away you go. Then click the little Img button you see above the text entry box when you're posting a message, paste in the url of the xs.to reference where you saved the image then click the Img button again. It's easier than it sounds. I think it's done this way to avoid Steve having to provide too much server space!

I'm on vacation i nNew England; FABULOUS roads; I'm in a rental car with the wife and kids

Cheers
Geoff