This o-ring replacement is a simple job, but it pays to do both at the same time. Take both banjo union nuts off so you can remove the oil feed pipe out of the way. The easiest way is to take the rocker covers off so you can see the rockers, then rotate the engine to a position where one of the rocker boxes has both valves fully closed (if necessary, slacken the the tappet adjusters to take the load off). Then you tap the shaft through until the o-ring is an inch or so clear of the housing. Now you can remove the old o-ring and clean up around it. This next step is where you need the special tool to do the job properly. It's simply a sleeve with a tapered bore which compresses the o-ring and guides it into the housing without damaging it. They are cheap to buy and should be available wherever you buy your Triumph parts. Slip the guide sleeve over the end of the shaft, then fit the new o-ring in its groove and smear some grease on it. Hold the sleeve flush against the housing and carefully tap the shaft through it and back into place. Repeat this process with the second rocker box and refit oil feed pipe, preferably using new copper washers. Even if you didn't have to slacken the tappets, it would be wise to check the clearances as the shafts may have rotated during the process and affected the clearance. My 78 T140V has only had a leak on these once in its 46 year life, although I did change them both again as a precaution 3 years ago when I did a top end overhaul. The important thing is not to damage them when you install them - simple with the guide sleeve, difficult without it.

@MadTinkerman

2 ай бұрын

@rickconstant6106, you're right! I should have replaced both of the o'rings at the same time. The intake one (which I did not replace) is on my to-do list. Thanks also for letting me know the process you follow as I'll be sure to either loosen the valves and/or ensure both valves are closed before doing the work. This makes good sense and something I should have done when I did the exhaust side. Thanks Again! If you haven't already, please subscribe! I would really appreciate it :) Cheers!

Wow, my old favourite English bike from back in the day.

@MadTinkerman

3 ай бұрын

Hi @ArtistisMe, just this morning I went out into the garage and looked at the bike with my morning coffee, and the bike truly is a work of art. Reallly appreciate your comment and interest, and glad to hear this old Triumph was one of your favourites from times past. Cheers!

When I see a repair like that I'm scared to see what I'll find underneath it, because who would do that in lieu of just replacing the o-ring unless there's a bigger issue? In this case, it looks like there wasn't a bigger issue which is good. I have the tool for the o-rings, but I don't think you need it. If you watch the Lowbrow Customs Triumph 650 rebuild series (which is a great series) Todd just knocks them in there. It may or may not shave a tiny bit of o-ring, but it'll still be oil tight, I've done it both ways. I can't imagine that rubber band and brass compressed the very o-ring much. The actual tool is a super tight fit on the o-ring. I wonder if a small clamp would work, like a miniature piston compressor.

@MadTinkerman

2 ай бұрын

Hi @daveco1270, I know what you mean about the 'Glue' approach to fixing that rocker shaft leak. Had me a bit concerned too, but as I go through the bike, so far everything else appears to have been maintained relatively well. Fingers crossed. Regarding the rocker shaft o'ring install, I think you are right that just pounding it in would work well too. With the method I used with the brass shim stock, the rubber band didn't provide any meaningful tension but just intended to hold the shim stock in place. The leading edge of the shim stock was placed into the hole first and then as you pound it into the hole it creates the tension to compress the o'ring as you drive it into the hole. Copied this technique from Unilad (youtube channel) who used a similar method with a thin feeler gauge. The rubber band was just to hold the brass shim in a circular shape around the shaft. Hope that makes some sense :) So far so good and it doesn't leak ...well, not yet :) You're right LowBrow Customs / Todd is amazing and really enjoy those videos. If you haven't already, please subscribe! I would really appreciate it :) Thanks Again!

A very rare Trimuph lol, Great vid man.

@MadTinkerman

3 ай бұрын

Hey @FuriousGriffin, thanks! It's a fun project! Appreciate the comment!

@FuriousGriffin

3 ай бұрын

@@MadTinkerman Check the spelling Chuck. :P

@MadTinkerman

3 ай бұрын

Fixed it. Thanks Buddy :)

It shaved a sliver off the O-ring as you drove it in, pretty much the same problem we all have I think. It may be fine, lets see if it leaks or not.

@MadTinkerman

2 ай бұрын

@paulwoods682, very observant of you! Yes it took a tiny sliver off the top of the o'ring, but so far so good. I have taken it on a few rides and so far zero oil leaks. I should have tackled both of them at the same time, but plan to do the other one here in the coming weeks. Thanks again for the comment!

I would change them both bud, if the one is that brittle then so's the other. Always grease o rings to help them squeeze in.

@MadTinkerman

3 ай бұрын

Hi Bill, great advice! I'll do the other one and use some grease instead of oil during the install. Appreciate the guidance :)

@FuriousGriffin

3 ай бұрын

@@MadTinkerman Anytime my friend

A carpenter's claw hammer shouldn't be in a mechanic's tool arsenal!

@MadTinkerman

23 күн бұрын

@ericleger8158, hysterical! I literally laughed out loud when I read this comment :) You're so right! I need to source a brass hammer or something a bit more suitable. Thanks so much for the comment and suggestion! Cheers!

Orange liquid gasket, shit.

@MadTinkerman

3 ай бұрын

Hi @arnievanderest5561, yeah not ideal but was a relatively easy process to remove. Time will tell if I've solved the leak or not. Finger crossed :)

Its a rocker box

@MadTinkerman

2 ай бұрын

Hi @paulwoods682 really appreciate the info, and thanks for letting me know the correct term to use. I do these videos in one take and sometimes the right term doesn't immediately come to mind :) Cheers!