Clutch pushrod question

[GeorgiaGuzzi]

Is this picture the clutch pushrod that I need to put the 6 o-rings on? May seem a silly question but I want to be sure and not assume.

Thanks, Robert

[guzzisteve]

Yes, in & out from the back. That's how I do it.

[Tom H]

Yes that is the rod you put the O rings on. But....... On the other end under the outer body, throw out bearing and inner body.

Tom

[Antietam Classic Cycle]

http://thisoldtractor.com/moto_guzzi_loopframe_clutch_push_rod__installation.html

[Cdn850T5NT]

Only loop frames? or also Tonti's?

[Antietam Classic Cycle]

Only loop frames? or also Tonti's?

Applies to 4 spd. and 5 spd. big-block transmissions no matter what frame they're in.

[GeorgiaGuzzi]

Thanks very much everyone! Especially thanks for the link to this old tractor. I had not looked under that section bc my bike is a Quota. Info like this is why a donation and trying to keep my whining to a minimum is the least I can do!

Will I need slide one on the end? There’s an o-ring on the end that is not flush and looks like it’s just hanging on. I haven’t touched the transmission yet. Getting the motor ship shape then on to the transmission.

[pehayes]

Will I need slide one on the end? There’s an o-ring on the end that is not flush and looks like it’s just hanging on. I haven’t touched the transmission yet. Getting the motor ship shape then on to the transmission.

Please clarify.  You show a picture with an o-ring on the FRONT end of the throwout rod outside of the input spline.  Are you saying the transmission came out that way?  With the o-ring in that position?  If so, then it sounds like someone else already converted this box from the original 2-cone system to the 6-o-ring system.  If so, they installed  the o-rings from the wrong end.  Since you have the transmission out,  you should remove the outer body, bearing, and inner body from the back end of the box.  Then remove the entire throwout rod from the box out the back.  Then inspect down inside the shaft bore to determine what possible o-rings or cones might be in there.  When you re-assemble, install the o-rings from the rear, one at a time.  Maybe show us a picture of the throwout bearing and its two race washers for possible wear.

Patrick Hayes
Fremont CA

[GeorgiaGuzzi]

The transmission is still in the bike. I dropped the motor. Have got several issues sorted with the motor, now turning my attention to the transmission. So yes, the o-ring on the front was already there. I haven’t touched it. So it sounds like I need to drop the transmission to verify everything for certain, yes?

[pehayes]

So yes, the o-ring on the front was already there. I haven’t touched it. So it sounds like I need to drop the transmission to verify everything for certain, yes?

Well, do you know of any other transmission functional issues or leaks?  Certainly, that o-ring does NOT belong where we see it.  So, my opinion is yes, you should remove the transmission, disassemble and inspect the entire throwout system, and restore with the 6-o-rings installed from the back end.

Patrick Hayes
Fremont CA

[wirespokes]

I must have been lucky so far on the three clutch jobs I've done in the last four years. None leak and I did nothing about the o-rings. Got another coming up so will pay better attention this time around.

By the way - what size are the o-rings?

How would I know if mine takes only four instead of all six?

[GeorgiaGuzzi]

Well, do you know of any other transmission functional issues or leaks?  Certainly, that o-ring does NOT belong where we see it.  So, my opinion is yes, you should remove the transmission, disassemble and inspect the entire throwout system, and restore with the 6-o-rings installed from the back end.

Patrick Hayes
Fremont CA

10-4. Appreciate the input. That is what I’ll do. I have the 5 speed kit from MG cycles already. Just pushes timeline back a bit. I must cultivate patience. 😁

[pehayes]

I must have been lucky so far on the three clutch jobs I've done in the last four years. None leak and I did nothing about the o-rings.

By the way - what size are the o-rings?

How would I know if mine takes only four instead of all six?

The original Guzzi installation is 2 rubber cones.  Years ago someone determined that a stack of o-rings would do a better job and 6 was the magic number. Several people have purchased large quantities of these o-rings and distribute them cheap or free.  Charlie Mullendore gave me mine (thanks!) but he and I have worked on several technical projects together.  This is the correct McMaster specification https://www.mcmaster.com/93125k19 but you have to buy 100!

Guzzi 5-speed takes 6 rings.

Greg Bender discusses the installation technique.  http://www.thisoldtractor.com/moto_guzzi_loopframe_clutch_push_rod__installation.html

Patrick Hayes
Fremont CA

[usedtobefast]

The transmission is still in the bike. I dropped the motor. Have got several issues sorted with the motor, now turning my attention to the transmission. So yes, the o-ring on the front was already there. I haven’t touched it. So it sounds like I need to drop the transmission to verify everything for certain, yes?

Have you been able to ride the bike since buying it and before pulling it all apart?  Any reason to suspect issues with the transmission? 

Reason I ask, for this pushrod work, on the Quota, you don't need to pull the transmission out to do the pushrod work.  I recently went through this with my Quota. 

So on this pic:



 

You can replace #7, #9, #11 from the back with the transmission still bolted in the frame.

But if you want to go through the transmission just for fun, then have at it! 

How many miles are on it?

[1down5up]

One thing I havnt figured out.....

Why do we need to worry about sealing the push rod (and plunger for that matter) from the rear to stop gearbox oil comming past, but not need to worry about the front into the clutch area - surely if it can leak backwards it can leak forwards along the ame rod in the same shaft?

[Old Jock]

The whole box sits in an oil bath, however the pushrod travels up the center of the Clutchshaft, which is hollow

The O Rings (or seals) isolate the rod when it enters the Clutchshaft, so it's always dry after the rod enters the clutchshaft (when the rod goes down the Clutchshaft center, it's now part of the clutch chest and isolated from the oily gearbox by the O rings/seals), the pieces aft of where the rod enters the shaft is open to lubrication

As far as the plunger that's isolated for a different reason, to stop the gbx oil coming out the end case and lubricating the rear of the bike and tyre

[1down5up]

Ahh ok, so the o rings/cone seals actually protect the clutch end from leaks not the rear end. And the plunger o ring seals that end.

[Old Jock]

That's how I understand it anyway



Not the best photo but all I had. This was just before I pushed the endcase down, the clutchshaft bearing obviously need lube, the pushrod has to be dry, hence the seals which sit in the shaft. The plunger O rings then sit in the endcase and stop the lube at the bearing getting out. I don't think the leak would be huge as it has to get past the shaft and sort of walk up there, but it would leak to some extent.

[GeorgiaGuzzi]

Have you been able to ride the bike since buying it and before pulling it all apart?  Any reason to suspect issues with the transmission? 

Reason I ask, for this pushrod work, on the Quota, you don't need to pull the transmission out to do the pushrod work.  I recently went through this with my Quota. 

So on this pic:



 

You can replace #7, #9, #11 from the back with the transmission still bolted in the frame.

But if you want to go through the transmission just for fun, then have at it! 

How many miles are on it?

Sometimes it finds a false neutral when shifting around 3rd gear. I think that’s a shim issue though. And the bike rides fine, shifts well. I had to dig into the motor bc of a plugged up crankcase breather tube. Since I’ve got it apart I’m doing some preventative maintenance. It did leak oil a little, but based on what I found I think most of the oil leak was caused by the crankcase being basically unvented, the cam plug being attached with a glob of silicon and the cam plug being loose enough to turn by hand. So I’m thinking oil was blowing out from the cam plug, which soaked the clutch plates etc. if I can pull it and inspect without dropping the transmission I may do that. 47k miles.

[Old Jock]

Could be the selector drum not shimmed quite right and causing a false neutral

When shifitng from 2 to 3rd you change selector forks, you have 3 forks, one for 1st & 2nd, one for 3rd & 4th and one for 5th. If its Ok then I'd just leave it until you have to go in there for something else

Theory on the engine sounds good to me especially if the cam plug was that loose. I'd also look very closely at the mains seal as well if the crankcase was getting pressurized. I'd replace it as a precaution, you don't want to do all that then go in agian. I believe some JB Weld the rear cam plug, never had to do it myself though.

You can crab the bike then pull the box off, you don't even need to drain the oil. That allows you access to the clutch pull it off and your at the rear seal and the cam plug.

[pehayes]

Some referred to 'plunger'.  Guzzi calls this the 'outer body' and numbered 10 in the above diagram.  The outer body contains an o-ring to seal it from leakage to the outside.  There are aftermarket outer bodies which are cut to accept TWO o-rings for better sealing.

The 6-o-ring kit goes into the position where the diagram above shows '#7-bushing' on the pushrod and below or internal to the inner body #8.

One caution. The rear cover is soft aluminum.  So the throwout hollow bore is also soft aluminum.  If the bike ever had a throwout bearing failure the spinning bits would easily damage the bore wall.  New o-ring seal to the outer body won't last long with a damaged wall to slide along.  The bore can be restored with a steel sleeve.

Patrick Hayes
Fremont CA