V7 Crank Failure. Engine Replacement Options? Now With Pics.

[Tom H]

I do not own a V7. But I have been wondering about engine options.

It appears that a fair number of V7's have had the crank failure. They seem to have late 2015 build date and 2016 model year.

I just helped a friend with a 2016 V7 Racer that the crank is moving back and forth. We pulled the trams and clutch to confirm that it was the crank. We then pulled the oil pan and found half of a thrust bearing down there. Have not pulled the engine apart yet.

So options..... Maybe you can get a free new engine, provided that you want to pay an authorized Guzzi dealer their shop hours to get it changed. And the dealer may have to fight to get you one. Hopefully you have a dealer that will fight for you.

Let's say you just decide to get another V7 engine because you don't want another one for the 2016 model year. You have the wet alternator and single TB. What newer engine build/model years would be a DIRECT replacement?

Would a 2018, 2019, 2020, ect. go right in?

Thank you!
Tom

[Dirk_S]

Assuming you're helping Mark out with the work that he's been doing and commenting on.

I'm not sure that many, if any, have really toyed around with replacing a V7 II engine with a III. I just don't think they're the type of bikes that invite owners willing to do that kind of customization. That said, my facsts are minimal:

The V7 III shares the same driveshaft as the V7 II. The mounts LOOK like they may be the same. The air intake looks a little different. The headers connect slightly different--how much exactly? Enough that headers for a III don't bolt right up to a II without some sort of mod, I'm not sure how much exactly.

The V9 uses a different drive shaft. There are some other internal differences as well.

This is something I've mildly considered recently, who knows just how many others have actually given it enough thought to compare part numbers. I'd ask one or two of the major dealers, like Cadre, Hamlin, AF1, etc.; seems they'd have a better idea over anyone else.
Not sure about ABS mounting, starter motor, evap canister, etc.

[Tom H]

Comparing part numbers is a good idea to see if a complete engine will bolt in. But there "could" be misleading info. For instance most big blocks like old 850-1000cc  (AFAIK) "essentially" use the same crank shaft dimensions. They just changed the front to use different alternators and the like. The clutch side is the same.

I would figure the V7 line would use the same basic crank, but change the nose to suit the need of that year electrics.

Comparing engine P/N would lead to the same problems. As in, different P/N but it bolts in the same. You would need to match a wiring harness for instance to make the change. Or it could be as simple as they changed the look of the rocker covers or oil pan or the like, hence the new P/N for the complete engine.

Piagio said this is a one year engine, nothing else fits. I just find that hard to believe. But then again, maybe a harness or the like is the difference. Change that part, all solved. But they wont tell you that.

ABS is frame mounted, not connected to the engine. Uses the regulator mount to hold it in place.

Thanks so far!!!
Tom

[Cam3512]

I was at Jim Hamlin’s a few years ago, and he had a faulty V7 II engine on the bench.  He had just replaced it with an entire new engine under warranty.  He explained and showed us there was too much end play in the crank bearings. The back and forth of the crank gets worse, and eventually destroys the engine. 

[guzzisteve]

If it isn't much play just put in new stuff. Parts are cheap. Block comes apart in pieces, like an Asian motor.
Not a bad job, I'd charge a grand. But that's me, I done my share of smallbock blocks.
I would press the warranty issue if he found the part that fell out on assembly.

[Antietam Classic Cycle]

If it isn't much play just put in new stuff. Parts are cheap. Block comes apart in pieces, like an Asian motor.
Not a bad job, I'd charge a grand. But that's me, I done my share of smallbock blocks.
I would press the warranty issue if he found the part that fell out on assembly.

It had nearly 1/4" end float. The flywheel was grinding away at the engine case it was so bad. Mark already has it apart, along with another one or two that he bought with the same issue.

Moot point anyway since Mark's customer doesn't want to fix it now.

[LowRyter]

this is unacceptable under any circumstances (unless it was run out of oil).

I thought the small blocks were robust, under stressed.  No?

[Muzz]

Is this the model where they were sent out with only half the complement of thrust bearings fitted?

[Brand X]

They will at least work with you.. I am just waiting till the Portland store opens. When I get the bike there, I just need to contact them.Just so the Moto Guzzi technical team can work along with the dealership regarding my Stornello

If Piaggio has not been contacted, it kind of hard for them to get around fixing this issue...

[Frenchfrog]

Years ago I helped a friend who had the same fault on his V50 2 ( due to running insufficient oil ) .He had the casing and crank resurface and an oversize set of shims made up but frankly I've no idea how long it lasted...

[Tom H]

Well it seems I asked a question that nobody has an exact answer for. Maybe these are too new for anybody to have needed to mess with changing a worn out engine with a newer version of it.

Thank you for the thoughts!!!
Tom

[John A]

I have a V65C that had the thrust flange failure. When I opened it up, the half moon thrust washers had fell out and the crank flange was wearing into the case. Ugly. I had the flange welded and ground back, it’s nitrided so it gets pits when welded and takes someone with skill to do it. The case had enough meat left to be dimensionally ok but it lost the register that holds the half moon thrust washers in place. I drilled and pinned them in place with brazing rod. I added an oil hole to the outer thrust face from the bearing feed. It’s been working for 30K miles, although it hasn’t been ridden much the last eight years since I got a Jackal for Deb. I thought about finding a newer engine for it but now it gets used so infrequently I’ve lost interest in that but I’d do it if I found a good engine that fit. It would be fun to stuff a 750 in there so I’m interested in you finding out what might fit what.

[Frenchfrog]

Looking at the period out numbers the 650 was a tad more powerful than the later 750's.Possibly a bit less torque though.Having said that they updated a few things in the valve gear on the 750 lump  which would be nice to have on the 650 too.
The issue with replacing the engine that suffered the crank failure would to be certain that all the ignition and injection bits were the same.I think it was the v7 /3 that had very different throttle bodies and ecu but not certain...so unless you are prepared to change the whole shooting game there could be serious headaches doing a swap.Dimensionaly there are also likely to be differences as I seem to remember that the later engines have a different alternator ( oil bath type ) and maybe slightly differently canted in the frame to improve handling.The later V 7's were continuously updated over the decade  ( injection, ecu, 6 speed gearbox etc...), so you want to check everything out carefully.

[Kev m]

Some random answers to thoughts on this thread:

* Cam, Hamlin told us that the crankshafts in question were out of spec undersized and that allowed the motion that eventually let the thrust bearings fall out of place/dramatically wear etc.

* I thought I remembered chassis/engine mounting changes occurred with the 2016 V7II AND AGAIN with the 2017 V7III. If I'm remembering correctly that could complicate it.

* I thought someone here said that the crankshafts changed between the V7II and the V7III, that the three and later were pressed together. I have no confirmation of this.

* The V7III has a host of differences with the II, from the hemi head design to the exhaust, to the chassis.

*  Piaggio NA was handling this under warranty, but sadly it seems some bikes actually saw few enough miles under warranty for this to surface in a reasonable time. But damn if I would still want to push hard on them. If it's an out of spec crankshaft that is the very DEFINITION of a factory defect. There shouldn't be a time limit on discovery.

* Mark has made only a few vague comments on FB about this possibly applying to some late 2015 wet alternator V7 MkI models, but I don't know if anyone has confirmed that with disassembly yet. I'm curious about that.

Bottom line I would think it would be a lot more work than beneficial to make a Hemi head motor fit.

[Tom H]

Frenchfrog. I looked up a few parts today between a 2016 and 2017 Racer. Block was different, TB/ECU different, clutch friction plate was different.

I'm really surprised the series changed so much. I figured one the single TB came out, they would be pretty much the same.

I think I will look at the TB/ECU combo between a few models for S&G. For instance, if an ECU for one model had a different map from the factory than an ECU for a another model, as in a Sport to a EV. The P/N would be different. Same ECU, but different map, new P/N.

Tom

[Tom H]

Some thoughts on Kev M's reply.

I have read too many things on what may have been the problem. Ranging from the crank not machined right to the thrust washers missing in an engine. If Hamlin say bad machined cranks, I am willing to go with that.

A thought on the "missing" thrust washers. If the bike had enough miles, maybe the washers could not be found. As in worn away ect.. A picture will follow of the thrust washes out of THIS 2016 Racer. The third pic shows the mangled washer on the right.

A though on the washer design. The thrust washers are two half washers. One on each side of the rear main bearing half shell. The odd thing to me is that they only used 1 half shell in each location. A main or rod bearing uses 2 half shells to make the circle around the journal. The thrust washers only use one half shell on each side of the rear main bearing, they do not make a circle around the crank.

The owner has given up on this bike. So we tore the block apart. One of the thrust washers was out of place and mangled. The other was still in place, but worn down to a razors edge.

If we had two new thrust washers, we had the specs for the end float and could have measured that. If we would have had the specs for the crank where the thrust washers ride, that would have helped to know if it was a badly machined crank. All bearing journals were in spec.

It's just a dam shame this had to happen to nice bikes.





Tom

[Antietam Classic Cycle]

I wonder why the thrust washer wasn't designed and made as part of the main bearing in the first place.

[Brand X]

Mine 2016 goes to the shop tomorrow.The shop is opening in Portland, and will be contacting the Guzzi tech team when their own techs look at the bike..The shop is not quite up, and running as far as being a Aprilia/Guzzi service center but is tied to the Guzzi place in Seattle, It won't hurt me to have it sit in the warehouse for a bit.. Nice there will be more dealers on the West Coast.. They have the Portland service # up on this site. Anyway i will have more info on how Moto Guzzi handles the out of warranty 2016 V-7ii with Crank issues . My replacement motor is a good on, and one way or another the Stornello will live again.

https://opmotorsports.com/

[Frenchfrog]

Tom H...like you I was surprised at all the incremental changes made : why on earth didn't they simply go for the latest hemi style engine ages previously  along with the single body TB and oil cooled alt ?! All of the know how and tech was there but maybe they had to use up old parts stocks?
Someone in the UK put in a twin TB  engine in a carbed small block frame and it all seemed straight forward enough ...keep us posted on the outcome anyhow!

[huub]

as a repair, making a pair of sintered bronze thrust washer is not that hard.
i would love to have a couple of those engines to play with...

[Frenchfrog]

That's exactly what we did years ago to the v50.

[Vagrant]

The real shame is Guzzi NA not instantly stepping up and replacing the engines. They F'd them up! Plain as that.

[Brand X]

Some think the Heron head works fine..The 2016 has the oil cooled alt,single throttle body.and six speed, Stornello tuning on mine..You could ask yourself why did Guzzi not go all out with Shift cam, dual overhead cams,water cooling, and a full ride by  wire setup in 2017? I fully expect my replacement engine in my garage to outlast me, and run as well as any small block needs too..