~ 71' V7 750 Special restoration

[F-22]

Hello,
I guess the time has finally come to get my V7 Special restoration underway. Had a GT750 project in the garage all summer. I bought this V7 in spring in Italy. It has a lot of patina, but it is running. My first concern was sorting out the import documents (gladly, it all went smoothly, I got it registered in just a week).

That's how it was on an Italian swap meet, before I bought it. Didn't imagine I'll ever own one, as the prices are quite steep here in Europe, and I just couldn't pass a good deal.
I did a short ride at home.

I may be among the youngest members here (21), but hopefully not the dirtiest.

After the ride, I popped of the heads. Sure enough, the cylinders are flaking a little. I plan on buying two new Gilardoni cylinder and piston sets. Should I completely tear it apart? How hard is it to get the engine out (can I leave the gearbox on?). I will probably remove the front cover and check the oil pump. I assume that if the oil pump is okay, the engine may be fine, and I will probably not go any further with disassembly. It's likely the bike was not used for a long time in Italy, as they have some odd complicated laws with registering old vehicles (many got "demolition" papers, and it's nearly impossible to register such a bike again in Italy, even if it is perfectly fine). The cylinders did not seem terribly bad, but some flaking was clearly visible. I hope to get to the oil pump tomorrow, to assess it further. I plan on keeping it original, with all the patina. Are the generators reliable? probably not a bad idea to check the bracket, as I heard/read that they like to crack.
Is there anything else that should definitely be replaced, as far as the engine is concerned? Or the gearbox and final drive?
Would anyone recommend any European supplier for parts? Currently, it seems Stein-Dinse has most of what I need, and the prices seem fine. I guess I really need to look for 83mm cylinders, but there seems to be plenty of 82,5mm kits (V7 Sport?). I doubt it would have an impact on performance, but I don't want any engine balance issues as the pistons may have a different weight. On Stein Dinse, they list 83mm pistons in the name, and 82.5mm in the description, but also just 82,5mm in the name on another listing, so I guess they have both.

Hopefully, I will post some more photos as I take the engine apart a bit more tomorrow.



Seems to fit well next to my Nuovo Falcone. The Falcone has 1900km, but I wouldn't be surprised if the V7 speedo turned over once. Currently, it shows 6000km, but I can't remember if it works. I think either the speedo or the tacho do not work. Noticed some models only had a speedometer, and it is practically the same one as in certain Fiat cars, with a different (Moto Guzzi) face.

Hopefully, this will go by smoothly. I study mechanical engineering (construction/design), and am still at least a year from finishing it up (perhaps I'll even continue on masters studies afterwards), so it may get really delayed, as I sometimes barely have any free time.

[canuck750]

Looks great! I buy a fair amount of Guzzi parts off HMB in Germany.

[Frenchfrog]

Really nice machine and congratulations for wanting to keep the patina whilst getting the engine sorted !
You really need to get right down to the crank and clean out the sludge trap as there is no oil filter on these bikes...checking all the bearings would be a sensible move too even thogh it will take time and some money.l
I use SD and HMB ....both give good service.I prefer HMB oil pumps and other special engine parts but that's only me as I've heard that some SD stuff that is newly made isn't very good.That's only hearsay.
There are also a couple of other Loop frame specialists in Germany...possibly the same guys who specialise in falcones so that would probably be worth looking up on google...I'm into Tonti and small blocks....

[F-22]

Well, I got it in the garage today.



And so it began.



The left cylinder head has some damage from a fall. However, it does not leak currently, and I think it will not be problematic to weld.



This second crack is a bit more annoying, because welding it would probably mess up the sealing surface even more (and it does not seem to leak as it is). The thread is bad. I'll probably get a helicoil or a custom threaded insert in it, and it'll hopefully be fine. As you can see on the photo, the top fin is just a little cracked and bent. Bending it upwards would probably break it off. It's still perfectly functional, so I'll just leave it.



Got it all off... On the top left, you can see a switch I found hidden in the frame tube/rail. It probably had turn signals originally, and someone removed them. Since I seem to have the stock switch, I'll probably go ahead and fit some old Italian turn signals too.



Got the other side off too.




The cylinders aren't scored or anything, but I think the flaking is clearly visible, even on the photos.





The piston actually looks rather good in my opinion. No deep damage.



The piston pin, however, seems bad. Theres a definite step that can be felt in the middle. It also seems like the small end on the right side wasn't "centered" properly, and there is some odd wear on the side of it. Pistons seem to come with new pins, but I guess the small ends will need replacing too.




The camshaft...follower s? do not seem too bad to me. There's definitely very little play when they are in the holes...





I also removed the generator and its bracket.



There's some nasty welding underneath. I hear this was a common problem. Not sure what the best solution would be, but I'm thinking some rib reinforcements at the sides might help a lot. Possibly, some kind of dampening soft aluminium washer between the bracket and the engine would help too. There was a rubber dampener  between the generator and the engine on the front, but it was seriously deteriorated. Again, perhaps I'd rather go with some kind of a soft aluminium washer here too, because the more movement it has, the sooner the steel bracket will crack.



Then I opened up the front...



Didn't know they used plastic gears, but okay...



Couldn't use the average puller tool on the plastic gear, so I just made a simple tool - there are two M5 threads in the sprocket for it. I used some flat ~4-5mm thick steel, drilled two holes, used long M5 screws and nuts, screwed the M5 screws until I could feel them on the other side of the sprocket, then tightened down the flat steel with the nuts (and used some copper between the steel and the shaft, to not damage it). It was on quite tight, but I tapped the centre a little with a hammer, and it fell off.


Sadly, the pump does not look that great. But I am not sure how worn is "too much". The gears have some rust down in the bottom of the teeth.


The driven gear seems to run quite near the housing, but the "free" gear has much more play. I do not know how much "play" a brand new pump has. There seems to be some rust on both gears.





The oil pump is kind of the basis for good engine running, so I think I'll have to replace it. Is there anything I could measure about it?
HMB seems quite decent. Currently, I'm looking at about 900€ for the cylinders, pistons, and the oil pump, and I expect the shipping, seals and some other stuff will easily take it to 1000€ or over. I'm really afraid of taking the engine further apart.


If I replace the pistons, cylinder, and the oil pump, I presume no damage should occur to these parts, even if the crankshaft is dirty and the plain bearings are bad, and I could restore the crank if it ever becomes a serious problem.

Maybe I will remove the connecting rods too. Then I'd see the condition of the crank, and if the oil pathways aren't blocked. The standard shells do not seem too expensive either (~13€, I guess for one, so 52€ for 4).




EDIT: Forgot to mention. One stud broke off when I was unscrewing it on the right side. It was the first one, so I was really afraid for the others afterwards. They were really tight. I bet someone seriously overtightened it. Is it safe to assume the 850's and possibly even the square fin models had the same studs? I removed the other nuts with a pneumatic gun, I guess the vibrations help a bit...


EDIT2: Someone in Italy is selling brand new cylinders for a bit less than a gilardoni set https://www.subito.it/accessori-moto/v7-special-palermo-275922251.htm. However, no pins, and I don't doubt they're original chromed bores. Still, since they are brand new, they'd probably last quite a while, but I think I'll go for a gilardoni set cause I definitely need piston pins...

[Frenchfrog]

Don't be afraid to open up the engine more .Thisoldtractor is a definite visit for you and you'll find masses of info with photos etc there. The pump body to rotor clearance is what you measure...plus check if the body is scoured.Get yourself a nice bottle of beer, google the site and relax...everything can be sorted !
Whereabouts are you...looks lovely and Alpine !

[F-22]

Thanks, I'll measure it a bit more tomorrow. I'm from Slovenia (quite close to the geographical centre, it pretty much takes me at most 2 hours to be at anywhere in my country). So yes, I'm right under the Alps.

[Frenchfrog]

I guessed right ! When my rebuild is roadworthy I'm thinking that Slovenia would be a good destination for a ramble...looks glorious !

[Antietam Classic Cycle]

I've never seen a plastic pump gear before, not something the factory installed, I don't think.

[rutgery]

nice bike, looking forward to see your progress!

[F-22]

I've never seen a plastic pump gear before, not something the factory installed, I don't think.

Odd indeed, but I'd be even more surprised if it not a factory part. Why would someone attempt make it? It's quite complex, with a metal centre and some kind of nylon gear riveted to it. Definitely something designed for mass production, not small aftermarket batches... Unless it coincidentally fits from some Fiat (perhaps not even that unlikely), I am sure it must be a factory Guzzi part. There's no wear on the gear either, so I guess it must function fine. To be fair, I'd rather see Guzzi kept the gear driven internals, even with plastic gears. The later chain drives (and their tensioner) were a very common source of engine problems.


Did the early Tonti framed 850T also had gear driven camshaft and oil pump? If those had steel oil pump gears, I'd be a little concerned (either they did not fit them originally, or they caused problems and stopped fitting them).

[Antietam Classic Cycle]

Odd indeed, but I'd be even more surprised if it not a factory part. Why would someone attempt make it? It's quite complex, with a metal centre and some kind of nylon gear riveted to it. Definitely something designed for mass production, not small aftermarket batches... Unless it coincidentally fits from some Fiat (perhaps not even that unlikely), I am sure it must be a factory Guzzi part. There's no wear on the gear either, so I guess it must function fine. To be fair, I'd rather see Guzzi kept the gear driven internals, even with plastic gears. The later chain drives (and their tensioner) were a very common source of engine problems.


Did the early Tonti framed 850T also had gear driven camshaft and oil pump? If those had steel oil pump gears, I'd be a little concerned (either they did not fit them originally, or they caused problems and stopped fitting them).

Maybe an aftermarket part for a perceived problem that never really existed. I'd rather take my chances with a timing chain and dodgey tensioner than a plastic gear. If the tensioner doesn't tension, the chain just gets sloppy and rubs on the engine case. If a plastic oil pump gear fails, there's no oil pressure and the engine is likely damaged.

The 850-T never had gears, only chain. The Eldorado with engine no. 58535 onward and V7 Sport with engine no. 33448 onward had timing chains. 

[F-22]

Well, the engine certaintly ran before, and there is no visible wear on the plastic gear, so I probably shouldn't be worried about it. Really odd, since it seems Eldorados still had steel gears. This is a domestic market V7 Special, so perhaps they tried some low volume plastic gear production, or couldn't find reliable suppliers and stayed with metal gears... I guess it is possible that it is aftermarket, but it just seems really unlikely to me.

Finding 83mm cylinders seems to be difficult. Has anyone fitted 82.5mm kits, meant for the V7 Sport? I wouldn't want any vibration problems...

[Antietam Classic Cycle]

Well, the engine certaintly ran before, and there is no visible wear on the plastic gear, so I probably shouldn't be worried about it. Really odd, since it seems Eldorados still had steel gears. This is a domestic market V7 Special, so perhaps they tried some low volume plastic gear production, or couldn't find reliable suppliers and stayed with metal gears... I guess it is possible that it is aftermarket, but it just seems really unlikely to me.

Finding 83mm cylinders seems to be difficult. Has anyone fitted 82.5mm kits, meant for the V7 Sport? I wouldn't want any vibration problems...

https://www.stein-dinse.biz/product_info.php?products_id=3974 Out of stock at the moment, likely waiting on Gilardoni to finish the new batch.

In stock now: http://www.mgcycle.com/index.php?main_page=product_info&cPath=68_129&products_id=2127

Once when Ambassador sets weren't available, I installed V7 Sport sets. The 82.5 Gilardoni (Asso) pistons matched the original 83 mm Guzzi (Mondial) pistons in weight and the engine was very smooth.

[F-22]

Thanks, then I might just fit those if I can't find 83mm. I doubt there's a huge difference, as I know people fitted 1000cc kits on 850's, sometimes without any major impact on vibrations.
I emailed Stein dinse, but they do not know when they'll get them on stock. I find it really amazing they are available in the US, but hard to find in EU. I also emailed to HMB, I hope they have them, otherwise I'll probably order a 82.5mm set from them, and possibly even their new oil pump (still have to measure the current one, perhaps it is fine).

I understand a little Italian, but so far it seems the specialists in Germany and UK are way better organised/easy to find online, and any new part is way more expensive in Italy (they do have 83mm sets, but at 400€, I rather wait for Stein dinse to get them on stock and spend the excess on a new oil pump...). Hopefully I will order the parts this week, and they arrive next week so I can reassemble it soon.

[Antietam Classic Cycle]

I also emailed to HMB, I hope they have them, otherwise I'll probably order a 82.5mm set from them, and possibly even their new oil pump (still have to measure the current one, perhaps it is fine).

I think this set on HMB is 83 mm, it's just a typo on their part:
https://hmb-guzzi.de/Cylinder-Kit-V7-Special

If you've never ordered from them, do be aware that they rarely package the shipment very well. More than one person has received their cylinder kits with broken fins because of the total lack of any cushioning material in the parcel.

[Frenchfrog]

Italian based suppliers here
https://www.officine08.com/?session_id=r3mtt3o6pr2usi2kemdvp4h6s6 
https://www.agostinimandello.com/   no experiance with either of them but Agostini have an awesome reputation and are in Mandello for what that's worth !

[Antietam Classic Cycle]

Italian based suppliers here
https://www.officine08.com/?session_id=r3mtt3o6pr2usi2kemdvp4h6s6 

Thanks for this link, lots of good stuff I've never found other places. Seems they're currently out of cylinder kits as well:
https://www.officine08.com/p10846_cylinder-and-piston-kit-moto-guzzi-v-7-special.html

[Frenchfrog]

I just discovered them a few weeks ago..for once an italien web site that isn't out of the nineties either!

[Don G]

Try Teo Lammers in Holland for the cylinders, just scored a set of 82.5mm sport cylinders with broken fins for cheap. DonG

[Antietam Classic Cycle]

Try Teo Lammers in Holland for the cylinders, just scored a set of 82.5mm sport cylinders with broken fins for cheap. DonG

4 left in stock
http://shop.tlm.nl/en/cylinder-compl-v7special-130202000010-moto-guzzi

[F-22]

Thanks for all the help.

I removed the conrods today. They do not seem bad, and the crankshaft holes seem "free". There is one slight step that can be felt. Left big end shells seem *really* nice, like someone already replaced them, while the right side shell was chipped. Not sure what could have caused it, but the journal does not seem damaged. I'll probably try blowing some air through the oil holes, to try and clean or clear it as much as possible this way. However, my micrometer seized, so I'll have to measure the journals properly tomorrow (I think I shouldn't get too excited). If it's fine, perhaps I could polish the journal a little bit, to buff out any steps.

Is it common practice to replace conrod screws on the old V7's? They seem seriously expensive, so I guess I'll stick with the old ones.

I did measure the oil pump as best I could. It's just slightly out of specifications. I still think I'll buy a new one, just to be sure.

I think I forgot to mention that one cylinder head stud broke when I was unscrewing the right side cylinder. Broke right under the nut. I suspect it was overtightened once. I'm glad the engine bottom end threads are fine. Talked to a friend today, and he has spare 850 engines for parts, and will give me one, so at least I have that sorted for now (I just hope the T3 studs are still interchangable, but they probably are...).

Same friend also suggested to search for Fiat 126 parts (Polski Fiat...). He claimed the big end shells are the same. I checked some Fiat 126 manual online, and they do claim exactly the same crank journal diameter (44.013-44.044mm). I wouldn't be surprised if they used the same suppliers. The 126 is the two cylinder version, so the Fiat 500 probably had the same ones too. A set of four costs around 10€ in Poland (seems a single shell for the V7 on HMB costs more).

https://allegro.pl/panewki-korbowodowe-do-samochodu-fiat-126p-cqn-700-i7555925154.html

[F-22]

Well, I have searched a bit more, and it seems the shells should be the same, as well as a few other parts. I think I'll try my luck and buy a set of Fiat shells first, they seem so cheap that it does not matter if they do not fit.

I have found this Italian Guzzi forum:
http://forum.animaguzzista.com/viewtopic.php?t=23528
There's lots of information about which parts fit from Fiat models, especially for the V7 models - air filters, points, condensers, distributor cap, distributor rotor, ignition switch, they mention Fiat 124 valve springs, starter motor... Though most of these things aren't terribly expensive (and yet, an OEM Fiat part may have much better quality or is the same as an OEM Guzzi part but much easier and cheaper to find, while aftermarket parts may have worse quality).

[Rick4003]

Nice bike you got there, I have a v7 Ambassador too, it is 85% restored, but needs the new wiring loom fitted and lots of other small things. You know, the famous last 10%.

I would certainly try and take the rest of the engine apart if it has unknown milage and if it never was cleaned out before. There always seem to be a load of crud in the trap in the crankshaft. See some of Canuck750's rebuild threads for a nice walk through with nice pictures.

[F-22]

I have measured the crankshaft big end. It ranges from 44.01 to 44.03. Seems to be exactly what it should be, so I am quite happy. I will polish the journal as best I can, new shells, need to make new small ends, fit new cylinder kits, have the heads welded up and then hopefully ride it a lot next year.


The wiring is quite bad too. It sounds like the generator needs new bearings, perhaps also the brushes. I think I'll just make a neat new wiring loom for it, there aren't that many cables anyway. Lots of household wiring solutions on it currently (not sure of the english term, but those screw-connector terminals). I was reading about it a bit in Guzziology, and it seems it would not be a bad idea to add a relay or two to some parts of the system too.


Sadly, HMB did not reply to my email, and I am a bit cautious about making a 1000€ order from a company that won't even reply. So I'll probably order somewhere else. Stein dinse is out of stock (I ordered from them before, so I know they're alright). Gutsibits and TLM are a bit expensive (around 100€ more for both cylinders and oil pump, than from HMB). And yet, 350€ for a cylinder/piston kit does not sound that crazy either, so maybe I'll just order from them...

[Antietam Classic Cycle]

You might consider buying the wiring harnesses from Greg Bender, best quality harnesses available anywhere:
http://thisoldtractor.com/for_sale_wiring_harness_loop.html

[Frenchfrog]

Everyone 's on holiday since Friday night and were rushing to finish off as much as possible in the week before.HMB have always replied pretty quickly to me ....their pump is made by them and not the same as the SD one. Several guzzi mechanics I know of here in France will not touch SD repro mechanical stuff.

[Antietam Classic Cycle]

Everyone 's on holiday since Friday night and were rushing to finish off as much as possible in the week before.HMB have always replied pretty quickly to me ....their pump is made by them and not the same as the SD one. Several guzzi mechanics I know of here in France will not touch SD repro mechanical stuff.

I wouldn't know why - I buy Stein-Dinse parts through MG Cycle and a few exceptions (speedometer drive, clutch thrust piece) it's all been good quality, equal IMO to the factory parts. Just put one of their oil pumps in my V700 engine rebuild, compared all of the measurements I took from it to those from the HMB pump I put in a customer's bike. Identical. The only difference seems to be the HMB gears are supposedly Nitrided. The one from HMB took nearly two months to arrive! DHL was on strike, blah, blah, blah...

Oh, and any HMB part number with a "Z" on the end is sourced from Stein-Dinse.

[Frenchfrog]

I've had no issues Charlie but they refuse to fit the SD pumps, main bearings or drive box gears and as both of them are as experienced as you in Guzzi if not more so  I listened to them when rebuilding mine ....the only replacement I had was the pump though.

[Antietam Classic Cycle]

I've had no issues Charlie but they refuse to fit the SD pumps, main bearings or drive box gears and as both of them are as experienced as you in Guzzi if not more so  I listened to them when rebuilding mine ....the only replacement I had was the pump though.

Zero issues with any of the main bearings I've bought (approaching a dozen sets) and as I wrote above the pump is nearly identical. <shrug>. At Charlie Cole's advice I've never used any aftermarket rear drive gears from any source.

[Frenchfrog]

Good to know about the mains....I was relieved to find mine still in spec at 160,000 km.The pump was well out though so I put in an HMB one and that gives me over 4 bar at idle when hot  which agreeably surprised me !
We had the same stories about dodgy quality with british bike spares in the 80's ....it pays to check carefully and with a qualified eye.