The 8V cam recall: Pt 1

[zebulon]

In France, a griso 8v owner who already have the recall done break down his engine jsut a few hundred kilometers later.

 

Big noise coming from the left of the engine and immediatly after rear wheel blocked.

 

Actually waiting to have more informations from his dealer.

[macguzzi]

I am at the factory tomorrow should i bash a few skulls

[belfastguzzi]

In France, a griso 8v owner who already have the recall done break down his engine jsut a few hundred kilometers later.

 

Big noise coming from the left of the engine and immediatly after rear wheel blocked.

 

Actually waiting to have more informations from his dealer.

Thanks for that. I just asked the question somewhere else: if I carry on riding the bike with new parts but no inspection for further damage to bearings etc, could something nasty like that happen?

Do you know what condition the cam and tappet bowls were in when they were taken out for the recall?

[zebulon]

I must correct he made 2 000 km since the recall have been done.

 

They were already damaged, engine was making noises on the left side 2 days before the recall have being done.

 

So for this guy this is the 2nd engine trouble in 4000 km.

[Paul Minnaert]

In France, a griso 8v owner who already have the recall done break down his engine jsut a few hundred kilometers later.

 

Big noise coming from the left of the engine and immediatly after rear wheel blocked.

 

Actually waiting to have more informations from his dealer.

 

Or the dealer made a mistake when reassembeling the engine.

[luhbo]

Yes, a blocked rear wheel because of any eventual debris from the cam recall? To me this doesn't sound really likely. I'd think the same: either a fault from the dealer or another fault in the engine. Like the faulty conrod bolts on the early V11s.

 

Hubert

[belfastguzzi]

I must correct he made 2 000 km since the recall have been done.

 

They were already damaged, engine was making noises on the left side 2 days before the recall have being done.

 

So for this guy this is the 2nd engine trouble in 4000 km.

That was the same with mine, a lot of noise on the left side – and you can see why.

As for faulty re-assembly: maybe that is why Guzzi have issued another technical bulletin to emphasise that the tappet rods have to be put back in the right way. There must have been cases of them being assembled wrong.

The notice, thanks to Pete: a further 8V tech update

[pete roper]

That was the same with mine, a lot of noise on the left side – and you can see why.

As for faulty re-assembly: maybe that is why Guzzi have issued another technical bulletin to emphasise that the tappet rods have to be put back in the right way. There must have been cases of them being assembled wrong.

The notice, thanks to Pete: a further 8V tech update

 

Mike was asking if the pushrods are directional in some way?

 

To be honest I examined them pretty carefully when I had mine apart and they looked symetrical but since my new bits have been despatched by pack-pony from Sydney I"ll be doing the recall on mine in a couple of days and I'll double check.

 

Having said that I think what the issue probably was is that when the cambox is replaced on the head the rockers will tend to flop about. It is possible, if you're a complete retard, to have a pushrod off the rocker. If you then torque the stud-nuts that retain the cambox and head/barrel to the case down and ignore the odd feeling and tortured shrieks of living metal as the whole thing bends,snaps and breaks you'll end up with a whole load more scrap and another unhappy customer.

 

While you might like to think that this sort of thing is so obvious only a cretin could miss it if you'd seen some of the recent, inadvertant, modifications and 'Tuning Enhancements' on the bikes I've been working on recently you'd realize that tragically the reality is a bit more sobering.......

 

Pete

 

Looking at the bulletin again it does look as though there is some sort of machined groove arond 'em. I put mine back in as they came out but I might pop a rocker cover andhave another squizz this PM.

[zebulon]

Sure an error is always possible, but the dealer involved is probably the most technical efficient of France.

To be precise this is MotoBell who made the Daytona 142 hp that win french protwin championship in 1999, so not just a "simple" guzzi dealer.

 

Now as you told guzzi wrote the technical note like as*$^le

[belfastguzzi]

Sure an error is always possible, but the dealer involved is probably the most technical efficient of France.

To be precise this is MotoBell who made the Daytona 142 hp that win french protwin championship in 1999, so not just a "simple" guzzi dealer.

 

Now as you told guzzi wrote the technical note like as*$^le

In that case you would think that when the cams were first taken out, they would notice further damage, or the potential for further damage, through shrapnel/debris and additional grinding wear and tear.

Is there any more detail in the report that you have seen about this?

[mike wilson]

Mike was asking if the pushrods are directional in some way?

 

To be honest I examined them pretty carefully when I had mine apart and they looked symetrical but since my new bits have been despatched by pack-pony from Sydney I"ll be doing the recall on mine in a couple of days and I'll double check.

 

The way it's written (translated, actually) it seems to be saying that one side/flank of the pushrod should face the relative rocker. But, as any fule no, properly designed rods and such will be rotating anyway so that makes no sense. The only other way I could read it (which was a less obvious way to read it but made more sense) was that there was an "up" and a "down" for the pushrods but the pictures I have seen seem to show "dumbells" that could go in either way up. Even more confusing.....

[belfastguzzi]

The way it's written (translated, actually) it seems to be saying that one side/flank of the pushrod should face the relative rocker. But, as any fule no, properly designed rods and such will be rotating anyway so that makes no sense. The only other way I could read it (which was a less obvious way to read it but made more sense) was that there was an "up" and a "down" for the pushrods but the pictures I have seen seem to show "dumbells" that could go in either way up. Even more confusing.....

 

"The notches on the body of the rods

themselves must face the rocker (fig. 1)"

 

Hop etis h elps

I transla ted it back to Ital ian and retrabslatedit toEn glis. Orrather I gotamach ine todo. It.

 

Like most things in life, it's all to do with balance, or not.

 

"OPERATION 15 Refitting rods.

Particular care must be taken when the refitting rods.

The notches on the body of the rods must address the balance (Fig. 1)"

[Paul Minnaert]

JM, did his bike have problems before the recal work?

[belfastguzzi]

JM, did his bike have problems before the recal work?

Zeb said that, "They were already damaged, engine was making noises on the left side 2 days before the recall have being done."

 

That's the same as mine. Noise on the left side, before the recall work.

[Skeeve]

"notched side facing related rocker" s/b "grooved end toward rockers" from what I make of the issue. Seems pretty obvious in the Guzzi-supplied pic: the dumbells have a groove machined on one end near the pivot "ball," and these ends are both up toward the valve rockers in the pic.

 

The usual machine-translated Italian is certainly no help: in this case, a pic is worth probably 10,000 words!