Tranny oil leaking through transmission vent screw

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Rob
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Re: Tranny oil leaking through transmission vent screw

Post by Rob »

Zombie Master wrote: Mon May 17, 2021 12:42 pm So if the speedometer cable a that attaches to the rear of the trans has not been sealed, water can get into the trans. Does the trans oil look milky?
Good reminder!

1) Make sure your speedo boot is not dry and cracked. You can buy replacements.

2) Fill that boot with grease to keep any water that might get in from getting into the gearbox.

3) Take a small zip tie, and close off the top of the boot with it, where the cable enters.

I HATE coffee coloured oil! :evil:
Rob V
cpazambrana
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Re: Tranny oil leaking through transmission vent screw

Post by cpazambrana »

Rob wrote: Mon May 17, 2021 3:23 pm
Zombie Master wrote: Mon May 17, 2021 12:42 pm So if the speedometer cable a that attaches to the rear of the trans has not been sealed, water can get into the trans. Does the trans oil look milky?
Good reminder!

1) Make sure your speedo boot is not dry and cracked. You can buy replacements.

2) Fill that boot with grease to keep any water that might get in from getting into the gearbox.

3) Take a small zip tie, and close off the top of the boot with it, where the cable enters.

I HATE coffee coloured oil! :evil:
Yes the boot was not properly installed. Water May have gone in but the oil is not coffee colored. I changed it about two months ago when I bought her but it rain on me about two times before I noticed that the boot was not properly installed. I have taken her in two 80 or so miles trip since I cleaned the screw and She has not
leaked. I think now she is venting better.
1983 BMW R80RT
1976 BMW R60/6
Still looking for a Honda CB77 Superhawk
cpazambrana
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Re: Tranny oil leaking through transmission vent screw

Post by cpazambrana »

Zombie Master wrote: Mon May 17, 2021 12:42 pm So if the speedometer cable that attaches to the rear of the trans has not been sealed, water can get into the trans. Does the trans oil look milky?
No it doesn’t look milky but the boot wasn’t installed properly. She in good condition though.
1983 BMW R80RT
1976 BMW R60/6
Still looking for a Honda CB77 Superhawk
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Zombie Master
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Re: Tranny oil leaking through transmission vent screw

Post by Zombie Master »

cpazambrana wrote: Wed May 19, 2021 8:14 pm
Zombie Master wrote: Mon May 17, 2021 12:42 pm So if the speedometer cable that attaches to the rear of the trans has not been sealed, water can get into the trans. Does the trans oil look milky?
No it doesn’t look milky but the boot wasn’t installed properly. She in good condition though.
You can still seal it up with a sealant like RTV. :)
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cpazambrana
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Re: Tranny oil leaking through transmission vent screw

Post by cpazambrana »

Guys, the bike is running great and idles very stable. No vibration at speed and no strange noises. However, on idle she shakes from side to side. She’s been doing this since I bought her but out of curiosity I connected my carb tune and found that carbs are not synced. The readings are very different. I didn’t try balancing them because she doesn’t present any of the symptoms (fuel consumption is about 40mpg) of un synced carbs. The side to side shaking at idle is normal?
1983 BMW R80RT
1976 BMW R60/6
Still looking for a Honda CB77 Superhawk
Kurt in S.A.
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Re: Tranny oil leaking through transmission vent screw

Post by Kurt in S.A. »

Not normal. So you found the carbs not synched....what did you see to make that decision? Seems like if you find them not synched, you should work to correct that. Three regions for synching 1) idle mixture, 2) idle RPM, and 3) throttle cable tension. All should be done with a fully warmed up engine/carbs.

Kurt in S.A.
cpazambrana
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Re: Tranny oil leaking through transmission vent screw

Post by cpazambrana »

Kurt in S.A. wrote: Fri May 21, 2021 6:24 pm Not normal. So you found the carbs not synched....what did you see to make that decision? Seems like if you find them not synched, you should work to correct that. Three regions for synching 1) idle mixture, 2) idle RPM, and 3) throttle cable tension. All should be done with a fully warmed up engine/carbs.

Kurt in S.A.
It was me... and just me. When I discovered that the new specs for valves were .15mm and .20mm I readjusted them. Apparently I did not torque well the left side. It was almost completely closed. It was about .4mm. Readjusted them and now the carbs are perfectly synced. Thank you!
1983 BMW R80RT
1976 BMW R60/6
Still looking for a Honda CB77 Superhawk
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gspd
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Re: Tranny oil leaking through transmission vent screw

Post by gspd »

cpazambrana wrote: Sat May 22, 2021 10:21 am It was me... and just me. When I discovered that the new specs for valves were .15mm and .20mm I readjusted them. Apparently I did not torque well the left side. It was almost completely closed. It was about .4mm. Readjusted them and now the carbs are perfectly synced. Thank you!
That makes sense (not) :?:
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Rob Frankham
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Re: Tranny oil leaking through transmission vent screw

Post by Rob Frankham »

Certainly having one of the valves set to 0.4mm is likely to have an effect on carb balance and running in general and I'm glad you found it without any further ill effects. however, I think it would still be a good idea to carry out a full carb tune and balance. Any adjustment that you mafe prior to the dsicovery will have been made in a false state and will probably need readjuxtment now.

It would also be a good idea to closely examine threads on the rocker arm, the adjusting bolt and the lock nut. It isn't unusual, on high mileage machines, for the thread to become worn and for the adjustment to come loose... the fault may not be with your tightening of the adjuster.

Rob
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cpazambrana
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Re: Tranny oil leaking through transmission vent screw

Post by cpazambrana »

Thats what I meant. I was able to sync them with the carb tune after I readjusted the valves. She is running very smoothly now. The side to side rocking at idle is gone and the miles per gallon range is now at approximately 45 miles.
1983 BMW R80RT
1976 BMW R60/6
Still looking for a Honda CB77 Superhawk
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