Gearbox oil leak

[chaterlea25]

Hi All,
Wet belts indeed??  I had a look at the valve clearances on the Honda V twin engine in my ride on mower
It has wet belts to cams which are made of PLASTIC  I kid you not 

A dozen or so years ago I rebuilt the engine for a custom Triumph 650, it came with a belt primary and cutaway primary case  Road crap had gotten in and done havoc to the alternator and the belt and not much good to the clutch either
I rebuilt it with a new alternator most of a new clutch and a full primary case. The clutch took "normal" Triumph plates and standard roller bearing rollers. I bought a belt that would run in oil and added ATF to the case
It has not given any issues (AFAIK)

John

[jhg1958]

Just an update.

I removed the clutch and inner primary chaincase cover today. I was cursing as I did it, as it is not too long ago since I rebuilt the gearbox. Changed my mind when I found that I had forgotten to bend the tab washer over to lock the nut and it had backed off a couple of turns.   What a silly bunt.  So I am glad I looked into this.  The seal was a rattling fit and the obvious source of the oil leak.  Tempted to reuse the seal but given the trouble in getting here I will go for a new one.  Plus I will order a larger sprocket too.  Then I will remember to lock none the nut with the tab washer. 

Bloody stupid design of an oil seal.

John

[muskrat]

G'day John.
A bit off topic but I see the earth lead attached to the motor. Did you have trouble with the earthing of the electronic ignition? If so may be painting of the engine plates (mine are alloy).
Cheers
ps: may start a new topic if this goes too far.

[jhg1958]

Musky

I had no problem but when testing continuity after rewiring I got a high resistance from the engine to the negative side.  Decided to play safe with an earthing strap especially since there seemed to be a place to bolt to.

John

[jhg1958]

just an update.  I received the new seal and 20T gearbox sprocket. I glued the gearbox seal in with some instant gasket.  the new gearbox was a tight fit and I replaced the SRM nut and remembered to bend down the the lock washer so hopefully it will not work free again.

I had a bit of fun with the Cush drive nut.  Although I do not need to align the engine sprocket with the clutch sprocket I was unhappy how close the belt was to the rear primary chaincase cover.  I put all 5 shims on the crank to push the pull out.  All was going fine when I put the locktight on the Cush drove nut and tightened the nut flogging with a C spanner.  Tough as the locktight fluid set as I was faffing about.  I found out that with all the shims in place you cannot screw the nut up enough to get the split pin in. So more flogging the poor old C spanner and remove all but one shim. I cleaned the thread and applied some copper slip.  The nut went on easily without flogging the spanner.  But then had cold feet remembering all the traffic on this forum about this nut working loose.  So I took it all off, cleaned off the coverslip and applied locktight, tightening the nut up quickly.

What a silly bunt

Never mind been out and so far no pool of oil to be seen  

A question for all you clever bods out there. I judged the old gearbox socket as worn but ok to use.  Do you agree with me?


   
 

[berger]

10,000 miles in that unless you live on my road

[muskrat]

G'day John.
Looks good to me. Just needs a wash.
Cheers

[jhg1958]

I thought I would resurrect this thread as it is a related issue.  As I fitted a belt drive I was unnecessarily concerned that it may overheat with the primary chaincase cover on.  When I reassembled it I decide not to fit the gasket since there is no oil in it anyway.

After my eventful trip to Spain one of the issues was that the spindle (67-3116) in the gearbox became loose. I assume because the grub screw had backed off for fell out.   I managed to put it back in with some locktight on the motorway service station.

Now at home I have decided to work on the issue that have become evident.  To access the grub screw I had to remove the inner primary chaincase cover to find rust!  The run down to Plymouth was very wet and a fair bit of rain in Spain (oddly in the hills and not of the Plain  ).  Water must have worked its way in through the joint.

I will refit with a light copper wire brushing and some grease and hope it does not affect the belt.

John 

[chaterlea25]

Hi John,
Does the bike have a "Pearson "type sliding plate fitted?
The original sliding plate will leave a gap around the gearbox shaft when a belt drive clutch is fitted (NEB anyway)
I would not worry about the clutch over heating with a closed case, you are not racing it!
I see that you have the nice SRM(?) cush drive pulley 
I suppose you could leave out the drain screw or plug to leave any water escape ?

I have an Ariel and know if I have it out on a wet day that when I get home I must drain the primary case as water gets in, Ariel's only have a thick felt washer stuffed between the case and final drive sprocket

John

[jhg1958]

John

Yes I have the sliding plate behind the clutch although I never knew it was called ‘Pearson’ you are right in that it does not make much of a seal. I did not replace the felt washer as the old one was in fair condition and there would be no oil anyway.

I went over the top with the SRM cush drive. Knowing that a large twin could be a little harsh I thought it was the best idea. SRM messed me about no end with this. Forgetting to put all the parts in the package and then had some difficult phone conversations.  I am still not impressed as I broke a belt (not sure why) and when I called them they had no spares nor were they bothered it ordering one for me.  I went to a bearing supplier and they did me proud with quick delivery for a good price. 

It’s a great idea to leave the drain plug out.  I am not fond of riding in the rain, especially torrential rain and if I had not being going to a ferry I would have stayed at home. 


John

[Billybream]

The Pearson plate is an alternative to the std BSA sliding plate, mainly developed for Gold Stars, but can be fitted to A10,s. On both I think there is still a leakage path which can be sealed with silicon or similar.

[jhg1958]

Billy

I am no fan of silicon but sealing this gap is a good idea I wonder if I bought some new felt and made it tight around the main shaft would be sufficient to keep the water out. This combined with leaving out the drain plug, coating the steel parts and my reluctance to go out in the wet will do the trick.

I am not keen to remove the primary chaincase every wet trip

John

[limeyrob]

The case is designed to be oil filled so the clutch bearing, cush drive and crank seal are kept moist with oil.  Changing to a dry belt has all sorts of unintended consequences and in my view only makes sense on the track where the cover is removed between every race and the parts lubricated.  The clutch is now running as a fully dry clutch, OK it was never a "wet" clutch but there's not corrosion protection on the clutch or plates because it designed to be slightly oily.

[chaterlea25]

Hi All,
John,
The "Pearson " sliding plate is a snug fit around the gearbox shaft with a seal fitted so intended for oil but would still be a better job even with the seal removed.
The NEB clutches have a sealed bearing so no worries there.
I would lube the cush drive lobes with a high temp grease
I have the same parts intended to fit to the RGS whenever I get around to it.
I will probably make my own sliding plate?

John

[limeyrob]

My bike came with two sliding plates, a std one which I fitted, and a home made one that has been made to take an oil seal. It was a good idea but rather badly made so it got relegated to the parts bin. They had made a seal holder and brazed it to the plate but it was off centre and bent.  Done well it could work.  I think the problem is that it has to slide when primary is adjusted so the seal gets squashed one side.  It took me a while to get the grip on the sliding plate just right so it slid nicely.