Cross posting a serious problem from MGNOC list

[callison]

I'm cross posting this from the MGNOC list - with spelling corrections since my text editor insisted upon it...

------------------------------------------------------------------------------------------

 

Posted on 6/3/2003 at 06:37:32 AM by Mike Harper

 

I usually try not to add my 2 cents worth on tech stuff but there is a potential problem that in my opinion needs to be addressed by Guzzi and they are not really willing to share a lot of information on it.

 

We recently had an experience with a 2000 V11 Sport that was a previous "Demo" model bought from Moto Guzzi on one of the great purges of inventory. This bike had been the personal demonstrator of one of the employees at MGNA and had quite a few miles on it and we used it some on rides here so I am confident that it was not a problem with this particular bike.

 

The owner brought the bike to us with a loud knocking sound and told us that he had passed a long line of traffic and had run it through the gears fairly hard accelerating past the traffic and when he let off and slowed back down the knock was there.

 

Upon investigation we discovered that the connecting rod bearings were galled and destroyed. Luckily there was no other damage that we could find.

 

A call to MGNA for repair authorization and some insight brought the comment that this has happened before and mostly with completely destroyed engines as the outcome. It was obvious that they knew there was a problem and really did not want to discuss it.

 

Looking at the damage and the scenario in which this rod seizure happened and listening to their comments about this happening under hard acceleration it was obvious to me that the sport type sump with the removable (through the pan)filter is the problem. The oil pickup has been modified from the original design of the other engines that has the filter inside the pan causing you to have to remove the pan to change it. There does not seem to be a problem with the earlier design because the oil pickup is in the pan and oil is siphoned off through a hole in the bottom of the pan.

The Sport design has a siphon tube that is hanging down into the oil from above and does not reach the very bottom of the pan. There is some distance between the bottom of the pan and the tube that I would estimate at roughly 1/2 inch. Also this tube is located at the very front of the engine.

 

It is obvious to me that a combination of high RPM with the centrifugal force off of the spinning crankshaft. (this causes the oil to be forced away from the spinning crank creating a valley in the oil at the bottom of the sump and up the sides of the engine case) along with the hard acceleration causing the oil to also be pushed to the rear of the motor causing a possibility of the siphon tube to starve for oil and the tube to pick up a shot of air.

This will cause the oil pump to cavitate and oil pressure to the rods and mains is lost. Instant disaster.

MGNA indicated that they thought that this hard acceleration and the possibility that the oil might not have been "up to the mark" could have been the problem but this bike was full of oil and the fact that there was no other damage indicates that there was only momentary loss of pressure and once the oil was under pressure again normal lubrication was resumed.

 

This situation could be very serious and in certain instances could prove to be extremely dangerous.

 

In my opinion if you own a Guzzi Sport, Daytona, Centauro, new type LeMans or any other model that has this type oil pan, I would be very wary of this scenario or set of circumstances. I also would contact MGNA and request an official statement from them concerning this.

 

I believe that a recall is in order and that they should refit all existing models with this pan with a redesigned and safer part.

 

Mike Harper

[mikie]

This is good information to have - thanks for passing it on. I've heard somewhere about an external filter kit that can be bought for these applications. Would that be a fix to this problem?

[callison]

I don't know, but Mike Stewart has one. I'm going to wait for his more informed answer.

[Guest russ]

Sounds to me like a recall is in oder for some baffling in the pan. Maybe we should start pestering them.

 

Jaap, could you create a poll that we can send to them

[Dirtybill]

Memories of my TL1000S. 10,000 miles and the main bearing went south.

[Guest Brent]

This sounded familiar, so I did a search and found the following thread about peoples' oil lights coming on after hard acceleration/deceleration.

http://www.v11lemans.com/forums/index.php?...66cac5a0edf54c3

[Guest IanJ]

I've certainly seen my oil light come on a couple of times under hard acceleration -- good thing I'm generally light-handed with the throttle! I'd hate to think I was destroying the motor just by riding the bike... Sounds like MGNA and MG Italia have some (more) fixing to do... <_

[Cliff]

This problem seems to got back through the Sport 1100 range also. I don't think there'll be a fix any time soon.

 

Is there some oil additive that can protect for the few seconds of no pressure

[Mike Stewart]

Just the other day when braking hard for a stop sign, I noticed my oil light coming on. Not a good sign. My oil level was toward the lower mark on the dipstick at the time. This was on my 03 Rosso, I never had a problem on my 00 V11Sport which has the aftermarket sump. The Moto Especial sump is German made and has a center oil pickup the is pulled from the bottom of the sump (passages drilled through the sump). Raceco uses this sump and states no oil pressure loss when leaned way over or on hard acceleration or braking. The stock pickup is not centered and can cause oil pressure loss especially if a little low on oil. Moto Especial does not import to the US. I ordered it through MG cycles which went through Stein Dinse in Germany, so it ended up costing more since it had to go through two hands. You can also order it through Raceco. One thing that they don't tell you when you install the sump is, the sidestand looses the 6mm. bolt that bolts to the stock sump. With out that little 6mm bolt, your cast iron sidestand bracket will BEND! You can go with out it for a while, but you will notice your bike leaning farther and farther over. I ended up making a support bracket that bolts to the lower pan rail.

 

Mike

[Guest gavin]

Sounds like you could be right about a possible known problem by MG, I'm one of three (that I know of) in the UK that has destroyed an engine through big end failure.

MG, really Aprillia, replaced the entire engine without question 18 months and 8,000 miles, into the warranty - good service or cover-up???

However one of these is out of warranty and MG is refusing help, not even willing to do the parts at cost.

I really like the bike but this does leave me feeling uneasy about the lengh of my relationship with it.

[Murray]

You could always chuck a deep V sump at it more expense bu how cheap is a motor? intresting cause a friend had a Daytona RS and rode it hard but never metioned this problem (bike mechanic by trade). Athough admitedly on a blast we tend to build to a serious speed and hole it through the corners rather than play drag strip racers at traffic lights.

[docc]

I'm trying to understand how a deep sump would solve the starvation problem. I'm thinking it's more the modified pick-up than the actual sump.

 

Is there no way to modify the pick-up on the original set up?

 

Also, do you think a windage tray would solve the starvation?

[Mike Stewart]

I'm trying to understand how a deep sump would solve the starvation problem.

Docc,

 

The deep V sump is V shaped and is slightly deeper than the stock pan. The V traps the oil in the center of the sump and channels it to the oil pickup located in the center of the sump. Everyone says that the deep V sump will add extra storage for oil, I found this to be not true on the V 11 Sport, it would increase volume on anyother Guzzi that do not have the stock deep sump.

 

Mike

[dlaing]

So, could one put an extender on the sump pick-up?

Or is the solution to keep your oil at the Maximum level? or higher?

Or the baffling idea?

[jsciullo]

Funny you should mentin this. Just last week for the first time that I have noticed - the oil light came on & off a quick stop and start. I thought I was seeing things as it has never happened again and I have had it out 4-5 times since. Maybe time to add a little oil?

Jim