V7 II Broke Down, Metal Flakes in Crankcase = Poops.

[Dirk_S]

Last Saturday I was riding home from Maine with my 275 lb friend in my 200 lb sidecar. We did a good bit of secondary highways, not going any faster than 65mph. Sometimes there were some long uphills, but I didn’t usually go over 60 mph up them. Kept the rig between 4500-7000 rpm. Then I got a low oil light and heard a slight but peculiar, metal tinging sound. Pulled over right away. Dipstick read bottom line. Thankfully had some reserve oil in a 1L bottle, and poured it in. Started up and on our way. Within 1 mile, the metal chatter  got a little louder. Sounded like it was on the right side, but wasn’t positive since the sidecar might be amplifying and ricocheting the sound. Within 2 miles, the bike shut down on me. Next day, I trailered it home.

Compression test on both cylinders read 180 psi both sides.

Leakdown test today:
Left side = at 75 psi, the cylinder read only 1 psi lost in the cylinder.
Right side = different story—at 75 psi, the cylinder read 63 psi for a 15% loss. I heard air coming out of the engine oil filler hole as well as through the throttle body. Intake leak, it seems?

I checked my valve clearances on the right side— still reading 0.15mm intake, 0.20mm exhaust, just as it did when I set them 2000 miles ago.

I pulled off the cylinder head. Guess I’ve been running pretty rich:







Dropped the sump. Uh oh. Lots of metal flakes, both gray and copper/bronze colored:







Drained the gearbox, minor metal amount, tiny granules, and not a lot, I think it’s normal.

Decided to go ahead and remove the cylinder and piston. Cylinders didn’t appear to really have any scoring. But the piston connect rod does move a few mm, maybe 5mm, up and down the crank shaft. Should it shift along the shaft at all? Saw some metal flakes sticking around inside the crankcase as well. Guess we’re gonna have a drop-down, clean-up job.

Thoughts? Main bearings look like they might be gray? Wondering what’s the copper color from?

Potentially important note: 3000 miles ago I replaced the clutch with the help of a custom bike builder, neither of us ever had a Guzzi motor opened up in front of our eyes before, but he had auto mechanic experience, and once he saw it looked like an auto style block/clutch, he was game to help. Since replacing the clutch, pushrod, thrust bearing, and oil seal back then, I’ve never once felt the need to adjust the clutch, so my limited knowledge feels somewhat confident that the clutch replacement may not be the cause…I hope.

I really wish I had a mechanic for a friend at this point.

[chuck peterson]

Ouch

Sorry for your loss…that seems pretty destructive

On the bright side we’re getting tons of used V7’s coming up for sale used

Buy a motor and slap it in? I’m not sure rebuilding would be cost effective…I’d hate to see just the parts cost to repair

[jacksonracingcomau]

Ouch

Sorry for your loss…that seems pretty destructive

On the bright side we’re getting tons of used V7’s coming up for sale used

Buy a motor and slap it in? I’m not sure rebuilding would be cost effective…I’d hate to see just the parts cost to repair

Fixing motors that have run dry of oil always involves more than just the big end that’s knocking
You also get plenty of spares to use or help others with
V7 850 motor might come up cheap

[Dirk_S]

I’m willing to bet that I didn’t do a good enough job keeping up on the oil, especially considering that I ride in all conditions, more aggressive terrain, and now have a Sidecar attached. I was told by my nearest dealer a couple years ago that I should split my fluid replacement intervals in half.

I don’t mind doing this work if I have to and IF it’s doable. No garage, so yeah, I’d be bringing it in onto the kitchen table. BUT, seeing that I’ve never done this before, I know I’ll need to be aware of steps that need to be super precise. I imagine balancing the crankshaft is no easy job.  And making sure that every single metal flake is out of the crank case so as not to impede oil passage. My 300,000+ mile, former warranty service associate at a BMW dealership friend told me that the balancing and bathing to get all the debris out are not great kitchen table jobs.

Unfortunately, a lot of those V7 IIs have the undersized crankshaft, which makes the point moot, I imagine.

[moto-uno]

  Not too sure I understand your phrasing about 'moving up and down the crankshaft' ? Is this front to back or
up and down ? The latter is really bad !  Peter

[Dirk_S]

  Not too sure I understand your phrasing about 'moving up and down the crankshaft' ? Is this front to back or
up and down ?

Sorry—fore and aft, sliding.

[guzzisteve]

Here--------Bolt up--------------

https://pinwallcycle.com/product_info.php?products_id=45553057

[Dirk_S]

Can’t guarantee that the frame mounts are exactly the same. Plus, I’d have to get a new air box m, throttle body and exhaust, at the very least. Remember, mine’s the last of the heron head, not one of the hemis

[Dimitri_Harkov]

Fingers crossed you can get that sorted.
Would be a sad waste since you put so much effort into that very nice V7 II.

Cheers,
D.

[Dirk_S]

After chatting it up with a few mechanic friends, and reading your thoughts, I don’t have the money for a rebuild job, and I don’t see any good V7 II motors available. Just listed it. And salty liquid escaped my eye.

[Scout63]

After chatting it up with a few mechanic friends, and reading your thoughts, I don’t have the money for a rebuild job, and I don’t see any good V7 II motors available. Just listed it. And salty liquid escaped my eye.

I’m sorry Dirk.

[czakky82]

That sucks… so sorry.

[Brand X]

I’m sorry Dirk.

Not sure how many miles you had on your 2016 V-7ii? Still sounds like the same crank issue as all the other lucky ones. I still have not got a answer from Guzzi my 2000 mile engine in my Stornello.. (Crank thrust issue) Once it happened I went right to ebay and picked up a good 4000 mile 2016 Vii
If Guzzi helps me on my engine..(50/50 chance I would think) I will have one engine the good engine for sale. You can have first crack at it, and fo what I paid.. $1089.00 Just a thought...

[Dirk_S]

Not sure how many miles you had on your 2016 V-7ii? Still sounds like the same crank issue as all the other lucky ones. I still have not got a answer from Guzzi my 2000 mile engine in my Stornello.. (Crank thrust issue) Once it happened I went right to ebay and picked up a good 4000 mile 2016 Vii
If Guzzi helps me on my engine..(50/50 chance I would think) I will have one engine the good engine for sale. You can have first crack at it, and fo what I paid.. $1089.00 Just a thought...

I have 33,000 miles on my bike. With so many miles, I’m leaning toward the cause centering around me not doing a good enough job managing engine lubrication. There have been a couple times where I’ve run low, and the one instance early this spring where I filled too much.

I’d be very interested in your offer. I’ll shoot you a PM.

[Dirk_S]

I have a couple promising leads to a replacement motor. Trying to jump on whichever one I can get ahold of first without breaking the bank.

One of the potential purchases is a V7 II motor that had the infamous crankshaft issue. There’s also a used crankshaft available on eBay taken off a salvage bike. Assuming this bike didn’t suffer that bad batch issue, I figure I could purchase the crankshaft, new bearings, and put it all together myself, right? That said, I’m not fully sure on what I’m doing. Would I have to rebalance the crankshaft, and at what point? Are there other clearances, specs etc., not found in the service manual that I’d have to be mindful of? Anyone have any good links for home engine repair?

Thanks!

[Frenchfrog]

If I remember correctly it's the thrust bearing/shim that was not right on those engines. Seen a similar failure on a v 50 many years ago and custom shims were made after the crankcase was checked and cleaned up where it locates.All doable but not simple and maybe not successful in the medium to long term.I lost sight of that bike ( a mates) shortly after the fix was done so can't advise more than that.

[Antietam Classic Cycle]

I have a couple promising leads to a replacement motor. Trying to jump on whichever one I can get ahold of first without breaking the bank.

One of the potential purchases is a V7 II motor that had the infamous crankshaft issue. There’s also a used crankshaft available on eBay taken off a salvage bike. Assuming this bike didn’t suffer that bad batch issue, I figure I could purchase the crankshaft, new bearings, and put it all together myself, right? That said, I’m not fully sure on what I’m doing. Would I have to rebalance the crankshaft, and at what point? Are there other clearances, specs etc., not found in the service manual that I’d have to be mindful of? Anyone have any good links for home engine repair?

Thanks!

No, you should not have to rebalance the crank. These technical training videos may help. The B750 isn't much different than your engine.
https://www.thisoldtractor.com/moto_guzzi_technical_training_videos_eng.html

[Dirk_S]

If I remember correctly it's the thrust bearing/shim that was not right on those engines.

I’ve chatted with a few respectful dealers that we all know and love, and there doesn’t appear to be complete agreement as far as what exactly went wrong. Some say undersized crank. Needless to say, once put back together, I may ride it for another year, but not much longer.

No, you should not have to rebalance the crank. These technical training videos may help. The B750 isn't much different than your engine.
https://www.thisoldtractor.com/moto_guzzi_technical_training_videos_eng.html

Thanks, Charlie. I keep forgetting that Greg has service videos uploaded.

Before purchasing a new (or gently used) crankshaft, I guess I can inspect mine. Is it easy to tell if a crankshaft is damaged? Score marks? Do I only worry about severe scoring, or are scratches that I can’t even feel going to be troublesome?

[Antietam Classic Cycle]

I’ve chatted with a few respectful dealers that we all know and love, and there doesn’t appear to be complete agreement as far as what exactl. Some say undersized crank. Needless to say, once put back together, I may ride it for another year, but not much longer.

Thanks, Charlie. I keep forgetting that Greg has service videos uploaded.

Before purchasing a new (or gently used) crankshaft, I guess I can inspect mine. Is it easy to tell if a crankshaft is damaged? Score marks? Do I only worry about severe scoring, or are scratches that I can’t even feel going to be troublesome?

The crankshaft should not have any scoring, minor scratches can be polished out. It should be measured precisely, to make sure it's still within specification.

[Dirk_S]

Replacement motor purchased.

Please. The cheering is deafening. Calm down.

Jim Hamlin sold me the bad batch motor that he’s been holding onto. Almost bought one from Cadre Cycle, both offered at very reasonable prices, but I can obviously shave a few dollars and take a 4.5 hour sight-seeing tour down beautiful US Rt 84 <*sarcasm*>  to pick it up. Heading down tomorrow.

Since it’s one of the bad batch cranks, I’ll have to replace the crankshaft.

Next step, purchase bearings / seals / bolts, and start disassembling.

[AJ Huff]

Congrats!

-AJ

[Dirk_S]

Minor updates:

I’ll follow the engine service manual and tech videos and measure the crankshaft, con-rods, bearings, etc….or find someone to do it if it feels too daunting.
Charlie (Antietam Cycle) has been quite helpful.

Hamlin invited me to eat lunch with him and the rest of the shop mates when I arrived to pick up the engine. Goddang sweethearts they are.

Hoping to drop the engine this weekend. Picked up a used motor on Saturday. Unfortunately, it’s one of those bad batch engines with the undersized crankshaft, so I won’t be using that part. If the crankshaft from my bike is also bad, I have another used crankshaft on its way to me via ebay as a hopeful backup.

Converting the kitchen into a workshop. I’m often single, and I just realized I should’ve done this much sooner. Make your space work for you, they say.

Main bearings, big end bearings, thrust washers, rod bolts, oil seal, and piston rings all ordered (cost more than the donor engine off eBay!). Most are on backorder through AF1, estimated 6-8 week delivery (oh these Italian machines).

Now to start studying, getting acquainted with the entire process, and gathering the tools necessary for the task.

And yes—I do realize that there’s a high chance that a naive amateur such as myself might think I have it all together and in spec, and install the engine and turn her on, only to hear chakka chakka chakka chakka BLURBADA BLURBADA BLURBA RETCHETA RETCHETA PBBBBBBTTTTttt.

…but Danger wouldn’t be my middle name if I wouldn’t try.

[Brand X]

And yes—I do realize that there’s a high chance that a naive amateur such as myself might think I have it all together and in spec, and install the engine and turn her on, only to hear chakka chakka chakka chakka BLURBADA BLURBADA BLURBA RETCHETA RETCHETA PBBBBBBTTTTttt.

So that means everything is running right then? :

[Kev m]

DUDE, You're going through all this trouble and Mark Etheridge just bought a brand new crate motor for a 2016 Racer for only $2500!?!

[Dirk_S]

DUDE, You're going through all this trouble and Mark Etheridge just bought a brand new crate motor for a 2016 Racer for only $2500!?!

Mark has more money than me at the moment. Funds are tight thanks to the other work I’ve had done (and the sidecar stuff).

If I take my time, this rebuild will cost under $1300 and bump my knowledge and experience up.

I was going to post progress and pics, but if folks just think I’m an idiot for doing so, I’ll refrain and keep the excitement to myself.

I’m curious how others expand their capabilities.

[Kev m]

Mark has more money than me at the moment.

Funds are tight thanks to the other work I’ve had done (and the sidecar stuff).

If I take my time, this rebuild will cost under $1300 and bump my knowledge and experience up.

BTDT - good luck and keep posting....

[Vagrant]

JMHO, I don't think they designed the bottom end to be rebuilt on the V7. I hope it works for you.

[Dirk_S]

JMHO, I don't think they designed the bottom end to be rebuilt on the V7. I hope it works for you.

Vagrant, could you elaborate? Do you mean from a logistic / technical angle, or just cost / worth the time?

Watching the 750 Nevada tech videos posted on Greg’s site, I’m not seeing anything that stands out to my admittedly less-than-experienced eyes as not doable at home. Certainly, I’ll have to make sure that I take some careful measurements, but that’s not unlike other engine rebuilds.

[Stretch]

Good Luck to ya, lad!

                     -Stretch

[guzzisteve]

On all smallblocks they make 1 bearing or wear shim (that's all you get) crank sits in block halves. Once worn out of new limits it's toast. Same with end play once past limit of new shim (crank worn) weld it up & turn it to new spec. If block is worn it's toast.
It is not like a big block with different size mains.

Then there's the oil pump and all went through it--