At the end of my rope with my Cal II slipping...

[brider]

I've documented my issues with my Cal II auto slipping woes AD NASUEM here on this forum, and now that it's happening again, I am ready to finally throw in the towel and park it. Or, do a 5-sp conversion, if that's the cheapest way to go.

I figure there's not much market for the bike, at least in it's current condition. I've customized it over the years to suit MY taste, and it's admittedly looking really rat-bike these days. I wouldn't pay more than $800 for it, even if it IS rare.

ATF tank is topped up to the top, no leaks, just replaced the hex key itself, female pump drive is not rounded out. Will eventually go 70 mph down the highway with "coaxing" in the way that only Convert and Cal II-owners understand, and at that point seems to have real "pull", but come to a stop, or worse yet, sit in traffic, and the TC seems to pump dry and and just won't transmit MUCH to the rear wheel.....%^$@*#  maddening.

I figure a 5-sp conversion would consist of a clutch, transmission, swingarm, u-joint, and driveshaft. Is that about it?

[fotoguzzi]

you need FW and rear drive too..

you probably have leaky o rings (3) in the torq converter static shaft.. yep, they are buried deep inside the bell housing. the pressure to the TC bleeds out thru the old flattened and cracked o rings.

you don't want the ATF tank to be any fuller than the top fill mark, if you filled the tank to the top, that is too full.

[yogidozer]

brider, there is a guy in Ct. that might be able to give you some help. Chuck Peterson. he is a member here, has a couple converts

[brider]

Chuck Peterson, the name is very familiar, and I believe he may have even stopped by my house one time when I still owned my '74 LAPD. I'm sure he weighed in on my original rantings about my slippage problem.

But I am shamed by Fotoguzzi's observation about the leaky O-rings. I recall now discussions about these rings and their compatibility with types of ATF and such, and at the time, I convinced myself they weren't to blame. Now I'm convinced they are, because I've investigated everything else.

FOTOGUZZI: I'm trying to imagine how the leaky O-rings jives with my symptoms; idling at rest, low pressure/low flow, the O-rings allow enough by-pass to drain the TC? Then as revs build, eventually increased flow will fill the TC back up, still with some leaking, but the flow at higher revs is enough to overcome and mask the leaking? Then at a stop, the reduced pump flow again allows the leaking to drain the TC?

When the ATF leaks past the O-rings, is it scavenged back into the tank somehow, or should I see it pouring out of the bellhousing bottom vent/drain hose (nothing coming out there)?

ATF level in the tank is NOT beyond the top mark.

Can a tranny be pulled off the bellhousing without pulling the engine from the frame?

[mtiberio]

secondary return from the bottom of the trans to the tank is for leakage/overflow I suspect.

[kingoffleece]

Hamlin Cycles in Bethel can help.  Just outside Danbury.

[gwb_mg]

You say the ATF tank is topped up to the top only fill to the level indicated on the dip stick. Also drain the system and refill with Shell AeroShell Fluid 4. If all is well mechanically this should fix your problem. I use this fluid in both my '80 Convert and Cali II Auto and since doing so I no longer have a slippage problem.

https://www.shell.com/global/products-services/solutions-for-businesses/aviation/aeroshell/products/fluids-and-preservatives.html

[brider]

You say the ATF tank is topped up to the top only fill to the level indicated on the dip stick. Also drain the system and refill with Shell AeroShell Fluid 4. If all is well mechanically this should fix your problem. I use this fluid in both my '80 Convert and Cali II Auto and since doing so I no longer have a slippage problem.

https://www.shell.com/global/products-services/solutions-for-businesses/aviation/aeroshell/products/fluids-and-preservatives.html

I clarified in my 2nd post that the tank was full to the top mark, meaning the top mark on the dipstick. The only time I've seen in real life that type of confusion was when I changed the oil in the car of a girl I was trying to date, and I declared, after putting 5-qts in, "Good to go, it's full". She looked in the still-open valve cover and said, "It doesn't look full...".

I think I DID flush/refill with the fluid you're talking about, it was an Aeroshell fluid per MIL-H-....., a spec I got right here in this forum a couple of years ago, probably with your input. But it turned out that very soon after that my pump drive key rounded off, so that effect I think contributed to some of the symptoms for which I changed the fluid.

No, I believe my problems are indeed going deeper than that, and those O-rings are the culprit.

[rodekyll]

If O-rings, think Brad has it covered.

Is the problem 100% or does it come and go?
Any smell associated with the slipping?
What color is the hydraulic fluid, especially compared to new?  Does it smell fresh or scorched?
Have you ever repositioned the cooler or tank?
Are the hoses all running their original routes?
Have you ever removed and inspected the actual pump?
Any chance the hose form the tank to the pump has collapsed internally?
Could the cooler be plugged?
Have you ever burped the lines?
Have you ever inspected the pressure relief valve?


Also, how is the clutch?
Freeplay?
Smooth engage/disengage or notchy feeling?

[brider]

If O-rings, think Brad has it covered.

Is the problem 100% or does it come and go?
Any smell associated with the slipping?
What color is the hydraulic fluid, especially compared to new?  Does it smell fresh or scorched?
Have you ever repositioned the cooler or tank?
Are the hoses all running their original routes?
Have you ever removed and inspected the actual pump?
Any chance the hose form the tank to the pump has collapsed internally?
Could the cooler be plugged?
Have you ever burped the lines?
Have you ever inspected the pressure relief valve?


Also, how is the clutch?
Freeplay?
Smooth engage/disengage or notchy feeling?

See responses in red below:

Is the problem 100% or does it come and go? 100% now
Any smell associated with the slipping? Nope
What color is the hydraulic fluid, especially compared to new?  Does it smell fresh or scorched? Nice clearish pink, minty-fresh
Have you ever repositioned the cooler or tank? Yes, new tank prior to fluid swap to Aeroshell fluid
Are the hoses all running their original routes? Yes
Have you ever removed and inspected the actual pump? Yes, took it apart 100% when I replaced the hex drive shaft
Any chance the hose form the tank to the pump has collapsed internally? mmmm Maybe, I suppose I'll swap that out before I pull the tranny, but I'm not optimistic that's the issue
Could the cooler be plugged? Nope, checked that when I had timing cover off
Have you ever burped the lines? When I put it all back together with a replacement tank, new hex drive, and new fluid, I DID burp it, but I didn't really get any air out, it was all fluid?
Have you ever inspected the pressure relief valve? Looked at it when timing cover was off, just a spring and ball, looked OK as I recall...

Also, how is the clutch?
Freeplay? Adequate freeplay, clutch is not engaged at all when slipping
Smooth engage/disengage or notchy feeling? Smooth engage, but dis-engage has been notchy for years, like my old Eldo with a worn input hub. Always engages tight, though.

I recall periods last summer/fall when it worked great, but seemed temperature-dependent when it began to get cool outside. Continuing like a freight-train down this o-ring path, I wonder if the brutal winter contributed to the O-rings demise, as the bike sat in a 0-deg garage?

[rodekyll]

You seem to be covering the bases with your inspections.   ;-T  The part that is puzzling is that if you're not getting circulation, you ARE going to cook the fluid.  It will become a black-cherry-red or brown and really stink.  I just rounded out the hex shaft in my 'vert.  I got almost exactly two miles out of it before the noncirculating fluid lost its cookies -- I had to get off the bike, and with the engine revved up push it up the slope to the carport.  The tank smells fresh of course because the fluid never got back to it.  But when I pull the hoses on the transmission, LORDY!!!.  It smells stronger that guy at the airport who's trying to substitute Old Spice for personal hygiene and looks like it got a bad sunburn.

When you did the tank replacement, did you mount it back at the same place?  Is there any chance you got hoses mixed up at the tank attachments?

WHAT IS THE EFFECT OF RUNNING WITH THE FILLER CAP OFF THE TANK?  Is there any foaming?

Have you tried running with just enough fluid in the tank to cover the intake screen by about an inch (way below the 'add' mark)?  When I moved my tank to forward of the rear wheel (long wheelbase bike) it became important to keep the fluid level as low as possible while still having enough to circulate and cool itself.  More and it seemed to lose prime overnight and foam/pump out the vent at speed.  For some reason having the cap on or off and having the cap o-ring installed or not made a difference.  I finally found a fluid level that avoided all the bad stuff and performed well.  It was during this series of experiments that I came upon the aviation fluid as my preferred substitute for Dexron II. 


An o-ring failure in the shaft tunnel is very rare, but as has been pointed out, you shouldn't see a leak if it happens -- that 90º pipe on the bottom of the transmission would return it to the tank.  In my opinion, temperature wouldn't have much to do with an o-ring failure, but then I'm not a space shuttle surgeon, either.

We had another member (no longer with us) who had a similar problem and thought he'd solved it with new O-rings.  Unfortunately he turned the bike into a lawn sculpture for reasons known only to him, so we don't know if the problem was solved for the long haul or not. 

If you get into O-rings, the only shop I've dealt with that felt confident sending the right stuff was Moto International in Seattle.  I've tried to get them from other shops and usually get asked to provide the part numbers.  Don't try to match them with ace hardware stuff.  There are micro differences in dimensions between guzzi's stuff and generic hardware stock.  You can ask how I know or just trust me on this.

[brider]

You seem to be covering the bases with your inspections.   ;-T  The part that is puzzling is that if you're not getting circulation, you ARE going to cook the fluid. 

My argument (I think) is that I AM getting circulation, but at low pump-flow times (idling at a stop), the O-rings are not retaining the fluid in the TC and the fluid just circulates past them, into the case sump, then back to the tank. At higher pump-flow, the TC gradually fills up faster than the O-rings can let the fluid bleed by, so I get SOME drive back. But it's still circulating. I suppose what I CAN do is pull a banjo on the right-side housing and see if it smells. I am familiar with the fragrance.

When you did the tank replacement, did you mount it back at the same place?  Is there any chance you got hoses mixed up at the tank attachments?

No chance of wrong hose attachment, I took pics and studied the manuals well. Tank was put back in the original place.

WHAT IS THE EFFECT OF RUNNING WITH THE FILLER CAP OFF THE TANK?  Is there any foaming?

I have not done this, what will foaming signify?

Have you tried running with just enough fluid in the tank to cover the intake screen by about an inch (way below the 'add' mark)?  When I moved my tank to forward of the rear wheel (long wheelbase bike) it became important to keep the fluid level as low as possible while still having enough to circulate and cool itself.  More and it seemed to lose prime overnight and foam/pump out the vent at speed.  For some reason having the cap on or off and having the cap o-ring installed or not made a difference.  I finally found a fluid level that avoided all the bad stuff and performed well.

I recall reading your testament to the effect of running with the cap off, and to be honest, I don't love this bike that much or have time to experiment with fluid levels; it worked without issues for the first 37k miles of it's life without resorting to non-factory settings. I'M NOT  CRITICIZING THE VALIDITY OF YOUR OBSERVATIONS!!! I just don't have the patience to replicate those actions. 

If you get into O-rings, the only shop I've dealt with that felt confident sending the right stuff was Moto International in Seattle.  I've tried to get them from other shops and usually get asked to provide the part numbers.  Don't try to match them with ace hardware stuff.  There are micro differences in dimensions between guzzi's stuff and generic hardware stock.  You can ask how I know or just trust me on this.

I've dealt with MI many times in the past, however, at my last pump-hex-key failure, I called them and spoke to a parts person who had no idea what an Automatic was, and looked up a part called a "driveshaft", and sent me something no-way resembling the part I needed. I found out later the hex-drive was NLA, so I made one myself.

Greg Bender's site has listing for replacement O-rings for the I-Convert, and I THINK he has testimony that the factory o-ring dimensions are small, and gives P/N's for alternates.

At this point, I am convincing myself that my symptoms could all be produced by o-ring failures, failing to hold pressure or fluid level in the TC.

[rodekyll]

That's a reasonable scenario.  Something that might help prove it would be putting a restrictor in the return lines.  I did it by blocking banjo bolt holes.  I pressed lead shot into  a couple of the holes.

Foaming is a problem with hydraulic fluids.  I don't know enough about the science to explain it, but it happens with 'verts, especially when the tank has been repositioned or overfilled.  I have been told that the aviation-spec fluids are made to minimize the problem, but I talked to a helicopter mechanic that said he puts a foam/fluid separator on the overflows of his machines (gave me one to play with that's being held hostage in Idaho) because it's still such an issue with some systems.  Foaming fluid loses all its properties.

I guess it's been a while since I bought parts for my converts.  You're right -- there have been big changes at MI.  I think Tony sold me my last set of O-rings.  It won't be long until the only ones who understand these bikes are you and me.

[brider]

  I think Tony sold me my last set of O-rings. 

So you HAVE replace o-rings before!!? Do you remember if you had to pull the engine out of the frame, or if the tranny/clutch can be removed with the front engine mount intact?

It's been 20 yrs since I had to replace the sheared flywheel on my first Convert, and at that time I DID have the entire engine out, but I don't recall if I HAD to...

[rodekyll]

Yes, I've done the o-rings.  I pull my gearbox with the engine in place.  then I pull the fluid drive section free of the gearbox, remove the 5 bolts on the 'tube' flange and replace the shaft O-rings, the bearing seal and the flange o-ring.  Pretty straightforward.  Remember that there's a circlip on the fluid drive shaft.

On reassembly, there are four wrong ways to reinsert the tube.  Be sure you have all your oil holes lined up.  It helps to use some witness paint or peen marks to index the location -- or just note the holes in the tunnel and the holes in the tube.  Also, keep track of the five bolts you took fromm the flange.  They go into blind holes.  Substituting longer bolts can make for problems.

[fotoguzzi]

  Remember that there's a circlip on the fluid drive shaft.

On reassembly, there are four wrong ways to reinsert the tube.  Be sure you have all your oil holes lined up.  It helps to use some witness paint or peen marks to index the location -- or just note the holes in the tunnel and the holes in the tube.  Also, keep track of the five bolts you took fromm the flange.  They go into blind holes.  Substituting longer bolts can make for problems.

what he said

[brider]

Thanks, fellas! I appealed to the Convert Yahoo Groups forum for advice along these same lines, so if you see my post there, no need to reply.

I'll report back here during/after the repair, but at my pace, that may not be for a loooong time!

[brider]

Yes, I've done the o-rings.  I pull my gearbox with the engine in place.  then I pull the fluid drive section free of the gearbox, remove the 5 bolts on the 'tube' flange and replace the shaft O-rings, the bearing seal and the flange o-ring.  Pretty straightforward.  Remember that there's a circlip on the fluid drive shaft.

On reassembly, there are four wrong ways to reinsert the tube.  Be sure you have all your oil holes lined up.  It helps to use some witness paint or peen marks to index the location -- or just note the holes in the tunnel and the holes in the tube.  Also, keep track of the five bolts you took fromm the flange.  They go into blind holes.  Substituting longer bolts can make for problems.

Forgot to ask: WHY did you replace the O-rings? Slipping symptoms like mine, or was it just general maintenance/restoration? If it was to correct a slipping problem, did it work?

[rodekyll]

I did that particular one because the flywheel had broken.