1973 V7 Sport Cylinder Relining Millennium

[Richiez22908]

https://www.thisoldtractor.com/moto_guzzi_loopframe_engine_out__check_these_things.html

👍

Shaun

Thanks!!

[Canuck750]

Fit a new pair of proper size crush washers on the breather line fitting, I have had oil drip out of here after a rebuild, had to drop the transmission and remove the clutch to fix a 10 cent washer



JB weld up the back of the cam bearing plug while your in there.

[Richiez22908]

Fit a new pair of proper size crush washers on the breather line fitting, I have had oil drip out of here after a rebuild, had to drop the transmission and remove the clutch to fix a 10 cent washer.

JB weld up the back of the cam bearing plug while your in there.

Yeah getting a new pair and gasket for the other pipe in there. Also some liquid gasket for around where they enter/exit and silicone to dab along the hose. That site was very helpful.

I JB Welded the plug too... but yours looks waaaayyyy better. 



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[Antietam Classic Cycle]

Yeah getting a new pair and gasket for the other pipe in there. Also some liquid gasket for around where they enter/exit and silicone to dab along the hose. That site was very helpful.

I JB Welded the plug too... but yours looks waaaayyyy better. 



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I was once told that I "used too much sealer".  No, I only use enough to prevent leaks...

Anywho, I use two different sealers when assembling engines. On the breather pipe and rear main bearing flange gasket surfaces I use a light coating of Permatex 300. On the two bottom bolts of the main bearing flange and in addition to the crush washers on the return banjo, I use a liberal coating of Hondabond 4.

I don't use the factory lock tabs, preferring the same DIN 137B wave washers that Guzzi replaced them with.

[Scout63]

Fit a new pair of proper size crush washers on the breather line fitting, I have had oil drip out of here after a rebuild, had to drop the transmission and remove the clutch to fix a 10 cent washer



JB weld up the back of the cam bearing plug while your in there.

I think you just solved my problem Jim. Oil drip after rebuild and I know the rear main seal and transmission input seal are ok since I tore it apart to check.  Ugh. Going in again.

[Richiez22908]

Sooo... while waiting on the machine shop should Open the transmission? If so what do I look for? Or, since it was shifting and working well, just leave it?

Also... wheel and other bearings... should I pull and check?

Thank you!

[blackcat]

I think you just solved my problem Jim. Oil drip after rebuild and I know the rear main seal and transmission input seal are ok since I tore it apart to check.  Ugh. Going in again.

Make sure the breather hoses are not leaking which will also cause that drip.

[Antietam Classic Cycle]

Sooo... while waiting on the machine shop should Open the transmission? If so what do I look for? Or, since it was shifting and working well, just leave it?

Also... wheel and other bearings... should I pull and check?

Thank you!

If the transmission has never had the original break-prone shift return spring replaced, then I'd definitely open it up to replace that. Input shaft and output shaft seals are likely old, so those and all o-rings replaced as well. Replace the clutch pushrod "seal" with six o-rings (I supply them for free to anyone in the US).

Five-speeds can have a number of issues: intermediate shaft separation being the most common, but also bearing races coming out of the case or off the end of shafts. All of them can benefit from reshimming the shift drum.

Rear wheel bearing are tapered roller type - I'd remove the seals, clean and repack the bearings and install new seals. There are shims between one bearing and the central spacer, so don't misplace those. Front wheel bearings are a bit harder to remove, easy enough to grease them in place (with a grease gun and needle attachment). Swingarm pivot bearings should be cleaned and repacked. 

[Richiez22908]

If the transmission has never had the original break-prone shift return spring replaced, then I'd definitely open it up to replace that. Input shaft and output shaft seals are likely old, so those and all o-rings replaced as well. Replace the clutch pushrod "seal" with six o-rings (I supply them for free to anyone in the US).

Five-speeds can have a number of issues: intermediate shaft separation being the most common, but also bearing races coming out of the case or off the end of shafts. All of them can benefit from reshimming the shift drum.

Rear wheel bearing are tapered roller type - I'd remove the seals, clean and repack the bearings and install new seals. There are shims between one bearing and the central spacer, so don't misplace those. Front wheel bearings are a bit harder to remove, easy enough to grease them in place (with a grease gun and needle attachment). Swingarm pivot bearings should be cleaned and repacked.

Thank you!

[Richiez22908]

Soooo... Having fun trying to source a ream main bearing. Gutsibits in UK has them is quoting with shipping. Machine shop said that since all is still standard, they'd check the old one and polish it up if it was good to go again. I have to take it down to them durning the week so might next week.

Any problem with reusing if they give it the ok? Or am I asking for trouble and better off doing whatever I can to get a new one?

Thanks again for all the help!

[Tom H]

If you have a reliable crank shop checking out the bearings and crank, then I would go with what they say. If they give you the size numbers and they don't add up to the book specs, ask them why they say they are fine. IIRR, your bike is fairly low miles. Crank and mains can last 1 hundred thousand plus miles if treated nicely.

Tom

[Richiez22908]

Ok thanks. Aside from chrome damage, which apparently was not present on the crank or cam, you’re right, 12k is very little.

Thank you again… I’ll let them take a look. Worth knowing my options.

[John A]

I didn't mean to say you didn't.. but.. there is a learned "feel" in precision measuring. It is *easy* to be off by a half thousandth.. or more.. without considerable practice.

I learned from an old navy geezer who claimed he had a micrometer eye. He would even say what his tolerance’s were before he guessed. He had a knack all right for he was generally accurate.

[Richiez22908]

Hi all. All parts are ready and started reassembly. Gonna work on it in every available moment… it’s riding season in South Florida and anxious to get it on the road but still won’t cut any corners.

Speaking of which… gonna get the gear marks in the case measured tomorrow was told that if they’re less then .010” deep it’s fine. Was also told to check for pitting on the gear faces but don’t see any. A little on the shafts.

Thoughts? Not against replacing if needed but don’t wanna waste if not.

[cliffrod]

No idea about the specs and actual measurements, but that doesn’t look good.   if it was mine I would replace the entire pump.  The wear and grooves on the shaft will not heal, nor will they lend any longevity to the aluminum pump body which will in turn lead to impaired pump gear agreement which will lead to reduced pump efficiency and ever lower pressure….  It’s a downward spiral.

I know a new pump is not cheap. This is the time to fix it properly.  If not, you’ll be fixing it again.  That’s no fun at all.

Edit-  Specification provided in the factory manual were based upon normal wear of engine components over time, caused by incidental wear caused by minor debris in the oil stream.   I doubt engineers were anticipating the catastrophic failure of the chrome plating, with subsequent catastrophic accelerated damage to the oil pump and other engine components.  If so, they would not have used chrome plated cylinders.

In general, factory specs are accurate with no need for interpretation.  In situations like this where hindsight provides much better perspective, those same specs may not be fully adequate.

[Richiez22908]

I hear ya, and will probably just replace it. Just trying to get a good perspective. There wasn’t any catastrophic damage from chrome. Very little chrome was missing from the top of the cylinder and likely went out the exhaust pipe. There was no other damage within the engine. I’ve had every part out and inspected. Anything that was replaced was do more to just sitting and pitting than anything else. The pump was the only thing that fell out a spec microscopically, and I was told it was probably fine anyway. But you’re right, probably best to take this one last hit now, and not have to think about it in the future.

[Dave Swanson]

I agree with cliffrod.  I would leave that pump on the shelf.   

[cliffrod]

I was in a similar position when I did my engine the first time. 

The engine was stuck with heads removed (for years) & pistons frozen in bores.  there didn’t seem to be any significant chrome loss below the rings.  It was all at and above the rings, which made sense to me.   on typical iron cylinder bores with stuck pistons,  that’s also where most damage is found.   There was no grand chorus of advice regarding chrome issues back then, either- my bike wasn’t even 20 yrs old at the time.  So I did the obvious work and never dove into the rest of the engine.  2-3 yrs later, it started growling and required a full rebuild when I really truly couldn’t afford it. 

If I had to guess, my oil pump probably looked like yours when I first did the cylinders.  It bore the brunt of the initial damage from initial chrome loss but ran and operated ok following the first engine rework.  As miles accrued, it continued to deteriorate until it became a liability.  The combination of dismissing oil pressure plus any remaining debris then wiped out the bearings, crank journals, tappet faces, etc.

Had I known, I would have gladly gone the extra distance in the beginning.  Replacing only the oil pump at that point would have saved a lot of money, grief and lost time on my bike when I was still young  and riding more.

[Richiez22908]

I was in a similar position when I did my engine the first time. 

The engine was stuck with heads removed (for years) & pistons frozen in bores.  there didn’t seem to be any significant chrome loss below the rings.  It was all at and above the rings, which made sense to me.   on typical iron cylinder bores with stuck pistons,  that’s also where most damage is found.   There was no grand chorus of advice regarding chrome issues back then, either- my bike wasn’t even 20 yrs old at the time.  So I did the obvious work and never dove into the rest of the engine.  2-3 yrs later, it started growling and required a full rebuild when I really truly couldn’t afford it. 

If I had to guess, my oil pump probably looked like yours when I first did the cylinders.  It bore the brunt of the initial damage from initial chrome loss but ran and operated ok following the first engine rework.  As miles accrued, it continued to deteriorate until it became a liability.  The combination of dismissing oil pressure plus any remaining debris then wiped out the bearings, crank journals, tappet faces, etc.

Had I known, I would have gladly gone the extra distance in the beginning.  Replacing only the oil pump at that point would have saved a lot of money, grief and lost time on my bike when I was still young  and riding more.

Understood...this one had just 12k miles but sat for 19 years and was recently brought back to life ...but they didn't check, know about or address the chrome cylinders. After crying like a baby when I realized I should on another thread, in contrast, I have gone thru every inch of it. Had the heads redone, new valves, guides, tappets. Crank and cam checked and polished, cleaned out the sludge trap. cylinders religned at Millennium, pistons checked and measured. New rings, new rear main bearing and rod bearings, front bearing checked and within spec. All new transmission gasket set, shift spring, rear drive gasket set, rear wheel and rear end bearing seals and will repack with grease(fronts too but not removing the bearings). Also changed out all the cables, checked the drums and clutch plates...(they were recently replaced and all look and measure as good). Probably leaving stuff out but there's a stack of boxes and envelopes from MGcycle on my workbench. Fortunately, like I said...there wasn't much if any chrome damage. But certainly won't have to worry about any showing up in the future.

Looks like I will replace the pump now too... just looking for best source.

Thank you and sorry for that hassle you had... I'm very thankful to be getting all this done now... whenever I mange to get it done, lol.

[Antietam Classic Cycle]

IMO, the best pump is the one HMB sells, even though it's $$$$.

[cliffrod]

. cylinders religned at Millennium, pistons checked and measured. New rings, .

Curious- where did you get rings?  My original cylinders and pistons are still here on the shelf.  Might check them and get rings.

I’m glad that you were open minded about the input here.  We all mean well, even if it may have seemed like a big pile-on of know-it-alls.  Personally, I’m very happy that my mistakes helped someone avoid the same problems and angst that I went through.  You’ll have a fantastic bike when you’re done. 

All that remains is to properly adjust and tune the big front brake once it’s on the road.  Poor adjustment and fatigued brake cables are main issues of poor performance.  It’s amazing how a single stretched or broken strand in the wound cable will wipe out much of the brake’s efficiency.  The cable balance bar will rack and you won’t even be able to fully operate the good cable to have half a brake.  Watch the balance bar where the two cables end at the hand lever.  It should always remain in the same orientation when you pull the lever so both cables operate evenly.  If it tips to favor one cable, that favored cable indicates a problem needing address.  It will never be a 1-2 finger brake like a disc brake.  But if you squeeze that lever like you’ve got a pair, it works fantastic.  To me, it’s much of the character of the bike.

[Richiez22908]

Curious- where did you get rings?  My original cylinders and pistons are still here on the shelf.  Might check them and get rings.

I’m glad that you were open minded about the input here.  We all mean well, even if it may have seemed like a big pile-on of know-it-alls.  Personally, I’m very happy that my mistakes helped someone avoid the same problems and angst that I went through.  You’ll have a fantastic bike when you’re done. 

All that remains is to properly adjust and tune the big front brake once it’s on the road.  Poor adjustment and fatigued brake cables are main issues of poor performance.  It’s amazing how a single stretched or broken strand in the wound cable will wipe out much of the brake’s efficiency.  The cable balance bar will rack and you won’t even be able to fully operate the good cable to have half a brake.  Watch the balance bar where the two cables end at the hand lever.  It should always remain in the same orientation when you pull the lever so both cables operate evenly.  If it tips to favor one cable, that favored cable indicates a problem needing address.  It will never be a 1-2 finger brake like a disc brake.  But if you squeeze that lever like you’ve got a pair, it works fantastic.  To me, it’s much of the character of the bike.

I really am extraordinarily grateful for this forum and all of you in it. I COULD NOT and WOULD NOT be able to do this without it and all of you(heck wouldn't have known I needed to til/if the engine gave out).

Purchasing a Moto Guzzi... especially one this old... is a leap of faith. I have some mechanical background but there's no warranty and no service nearby(or almost anywhere). This forum and the global cult of Guzzi gave me inspiration and faith to do it.

I turn 50 in January... as does this bike... and am also Italian and always admired Guzzi's from afar...  so it was a 50th birthday gift to myself. The short time I had and rode it was just glorious... and affirming. I've had Harleys and a Ducati but this MG and it being of that vintage... it's like riding with an old friend. And I so look forward to doing it again.

Regarding the brakes... yeah I did that high wire act to get the fronts worked out. Initially it was like I had to send a text to Italy to let them know I wanted to stop, wait for a response... and with the time zone difference that always took a while(original anti-lock I guess?).

To be fair my bike right before this was a Ducati Scrambler 1100... it was retro but the brakes were eye socket emptyingly not.

I got those old four shoes working better but definitely needed new cables, so they're on. Rear actually was much better but replaced that cable and the clutch cable as well.

Thank you all again so much... can't wait to post video of it running. But I'm sure there will be a bunch before then.

[Richiez22908]

Curious- where did you get rings?  My original cylinders and pistons are still here on the shelf.  Might check them and get rings.

Sorry... this is where I got the rings:

https://www.dlastore.com/piston-ring-set-for-moto-guzzi-v7-sport-750cc-motorcycle-82-5mm.html

[Richiez22908]

Anyone know where I can get the tool to install the rear main seal? Messed one up using just a rubber mallet. MGCycle Carrie’s them for $35 but no stock. Foreign sites want a fortune. I’d gladly pay someone who has one to borrow it. Otherwise I’ll find a socket and just use that and the mallet.

Thank you!!

[Antietam Classic Cycle]

Anyone know where I can get the tool to install the rear main seal? Messed one up using just a rubber mallet. MGCycle Carrie’s them for $35 but no stock. Foreign sites want a fortune. I’d gladly pay someone who has one to borrow it. Otherwise I’ll find a socket and just use that and the mallet.

Thank you!!

Do you mean this one? https://www.mgcycle.com/index.php?main_page=product_info&cPath=80&products_id=2962

I have one I never use, will sell or loan it to you if you'd like.

[Richiez22908]

Yup that’s it!!

If you’d like to keep it on hand I’d gladly pay to borrow it as well as shipping not ways. If you don’t want it around anymore I’ll buy it. Up to you.

Thank you!!!

[Antietam Classic Cycle]

Yup that’s it!!

If you’d like to keep it on hand I’d gladly pay to borrow it as well as shipping not ways. If you don’t want it around anymore I’ll buy it. Up to you.

Thank you!!!

Pm'ed you.

[Richiez22908]

Ok got the tool on the way.

Another question... where can I get an oiling dowel for the new rear main? Or do I pull the old one and how?

Thanks again, again... and again!

[Antietam Classic Cycle]

Ok got the tool on the way.

Another question... where can I get an oiling dowel for the new rear main? Or do I pull the old one and how?

Thanks again, again... and again!

Remove and reuse the dowels from the old bearings. They should push out easily with a long punch or screwdriver.

[Richiez22908]

Remove and reuse the dowels from the old bearings. They should push out easily with a long punch or screwdriver.

Ok thanks... Original front main is good so don't have to do anything with that one... just the rear.

Thanks!