T140 Oil Pipe Junction Block

[RobinV]

Hello all. I am chasing down an oil leak on my 1978 T140. Not a major leak but a consistent one. I have ordered two seals and a gasket for the timing cover. My feeling is that it may be the oil pipe junction block or gasket. A question to those in the know; Is it possible to replace the gasket w/o removing the kicker cover? Or must I remove that cover to access the block? I appreciate the knowledge base here, and would also appreciate any tips. Thanks, Robin

 

[Rudie]

possible to replace the gasket w/o removing the kicker cover? Or must I remove that cover to access the block?

Depends. First you need to get a look from underneath; if the edge of the gearbox outer cover ("kicker cover") is not obscuring the oil pipe junction block nut, it is possible to get a 1/4" drive thinwall socket to the securing nut.

Then you have to hope the old gasket comes off the crankcase complete, because cleaning gasket remains off the crankcase will be extra difficult because of the restricted space with the cover in place and there's a gasket and block alignment pin additional to the stud.

Again because of the restricted space, you are also likely to have additional difficulty fitting the new gasket and refitting the junction block.

 

[RobinV]

Thanks for that Rudie. I will most likely then remove that cover for better access.
It looks pretty straightforward. I do not want to remove the transmission case cover at this point. Appreciate the reply.

 

[Rudie]

I will most likely then remove that cover for better access.
I do not want to remove the transmission case cover at this point.

If you remove the gearbox outer cover for access to the oil pipes junction block, good to redo the clutch adjustment after you replace the cover as some of the clutch actuation parts will come off with the cover.

 

[RobinV]

Thanks for letting me know. I will try to find a video or a succinct explanation for removal in a manual. I remember as a kid removing the top of a quadrajet
and turning the carb body over. Two ball bearings, of different sizes fell out. Oops.

 

[Rudie]

I will try to find a video or a succinct explanation for removal in a manual. I remember as a kid removing the top of a quadrajet
and turning the carb body over. Two ball bearings, of different sizes fell out. Oops.

Should not be any loose parts inside the gearbox outer cover.

If you look at the Triumph parts book for your bike, Gearbox Outer Cover drawing:-

. when the handlebar clutch lever is pulled, the cable inner rotates part #18 (also called "Clutch lever" ) around part #19 (Lever shaft);

. that rotation moves the three #20 balls out of the indentations in the #18 Clutch lever and #21 Thrust plate;

. because the Thrust plate is fixed in the gearbox out cover, the three balls rotating out of the indentations moves the #18 Clutch lever and #19 Lever shaft towards the drive side of the engine;

. the end of the Lever shaft presses on the end of the clutch operating rod through the middle of the gearbox mainshaft to the "Adjuster pin" in the centre of the clutch pressure plate - the rod transfers the lateral movement of the Lever shaft to lift the pressure plate and relieve the pressure of the clutch springs on the plates.

Normal clutch adjustment puts a desirable clearance between the "Adjuster pin" and that end of the clutch operating rod so, when the handlebar lever is in its normal position, the rotating clutch is not spinning the operating rod against the end of the Lever shaft.

If you remove and replace the gearbox outer cover to access the oil pipes junction block, because the #18 Clutch lever and #19 Lever shaft are mounted in the cover, it is not impossible you affect the clearance between Lever shaft, Adjuster pin and respective clutch operating rod ends. Redoing the clutch adjustment after replacing the cover ensures the clearance remains as desired.

 

[RobinV]

Thankyou for that. It looks to be a fairly simple operation then. And your detailed explanation is appreciated. I look forward to getting in there.

 

[Lordmac]

Hello all. I am chasing down an oil leak on my 1978 T140. Not a major leak but a consistent one. I have ordered two seals and a gasket for the timing cover. My feeling is that it may be the oil pipe junction block or gasket. A question to those in the know; Is it possible to replace the gasket w/o removing the kicker cover? Or must I remove that cover to access the block? I appreciate the knowledge base here, and would also appreciate any tips. Thanks, Robin

How about those oil lines? Those can leak and slobber oil all over the place. I had one leaking a bit and you can't really tell where it's coming from unless you turn the bike upside down and get in there and scrutinize with a surgical lighting system. Course, turning the bike upside down requires a bit of finesse and three or four strong men and a boy . . .

 

[RobinV]

I was able to replace my pipe block gasket. It was , as described here., a fairly easy procedure. I found the oil pipes block to be well fastened, not loose. I replaced the gasket and tightened the stud. Upon replacement of the cover, I allowed the kick shaft to move inward which released the spring from the locating pin.
I relocated it and prewound the spring. At this time the spring knocked out the pin which struck my finger at "lightning speed". It also took out a chip from the base of the pin. A bandage stopped the bleed. I found the pin and loaded the cover onto my Royal Enfield Bullet and off to the welder. He was just about to close for the day but aluminum welded the area. I came home and installed the outer cover. Next day I was concerned that I may have lost oil to and from the pump. After refilling the empty reservoir, I removed the plugs and kicked 80 times and then saw oil return. I kicked another 30 times and had strong oil return with oil lamp out.
The procedure was a success and my leak is gone after a test ride.
Always an adventure. Robin