Lario rehab project begins. What we've learned..

[Tazturtle]

Outstanding thread. You do nice work Chuck.

Kurt

[Chuck in Indiana]

I'm following with great interest as I have never seen a 4 valve Guzzi opened up.
Are the rocker arms bronze, copper plated, or?

I *assume* they are bronze. I'll look a little harder today. It's a lovely casting, isn't it? The small block in general is simpler and a little more evolved than the big block of that time. Too bad about that valve issue, the 4V is a great runner..

[Chuck in Indiana]

Outstanding thread. You do nice work Chuck.

Kurt

<Elvis/1> Thankya thankya <Elvis/0>  ;D

[misterg]

It's a lovely casting, isn't it?

Couldn't agree more, was just thinking the same thing myself as I was looking at your pic.  In fact, the Lario is full of beautiful castings, the Italians sure know their metallurgy!  The swingarm, the valve covers, the oil pan and oil filter cover, all gorgeous pieces of work!

[Chuck in Indiana]

Alrighty, let's do the Dis side cylinder.. new rings direct from the manufacturer.. I'd never seen a 4 piece oil scraper ring assembly like this and the photocopied directions were not legible. Googleing Deves 4 piece oil control ring installation brought up a pdf with detailed directions on how to install it. The internet "can" be a wonderful thing. 

You really need to check the end gap. Too little, and as the ring expands with heat, you have an interference fit. Not good. Push the ring in with the piston, eyeballing squareness. It's not rocket science.

Then, take a set of feeler gauges, and check the end gap against spec. That's kind of a fussy operation. Minimum on the Lario is .011". The second ring was fine at .013. The top compression ring "looked" too tight to me.. after all, I've been eyeballing thousandths for 50 years. <shrug> So, I tried .010. No Joy. .008 would go, and .009 was iffy. That ring may very well have broken in service.
So. Real engine shops have a special tool for ring filing. If you're careful, though, a mill file will do the job. Be gentle, watch each stroke to see where the material is coming off to keep it square. .003" isn't very much.. an RCH is a measured .002". ;D :BEER:

Ok, we're at .012, time to assemble the rings. The proper tool makes short work of that, after all we don't need a stress riser scratch on the piston from cave manning the rings on there.

I normally build chrome engines dry, but the platers said to lube everything. Yuck. Pour it on the rings and work it in, cover the cylinder wall completely.

Clean the ring compressor and adjust it just tight enough to make the rings flush with the piston. Just barely cover the top ring so the piston will enter the cylinder squarely. Here's where being too gentle will get you in trouble. You want all the rings to enter the bore with one swat. If you are too gentle, a ring will hang up. I'm not talking *smite* here  ;) but a rap. I used a piece of plastic I had laying around, and it went right in.

From here, it's the same operation as the Snot Dis side cylinder. Rotate the engine cw (seen from the front) to bring the D side to TDC.

Closed up. Now, I can quit worrying about having the engine opened up while I'm running another production job and chips are flying around.

edit for typo

[mwrenn]

This is an awesome thread!  Thanks for posting up all the pictures.  It will really help me out when assembly time comes for my 4v project.  ;-T ;-T ;-T

[Chuck in Indiana]

Ok, on to the electrical stuff. I think I mentioned that the switchgear was mismatched. and pretty well fornesqued. On the light switch I had High beam, parking light, and dead short. The other side worked, sort of, but was the wrong switch. Leroy pmed me and said he had some better switches. After an extended negotiation, we finally came to terms. He kept wanting less money than I was willing to pay.  ;D :BEER: I know those kind of guys, if you write them a check for more money than they ask, they won't cash it.  ~; At any rate, we finally came to terms, and a box came in the mail. Besides the switchgear, there was a CD of probably everything that is on the net for the small block, and an unobtainium trapezoidal master cylinder reservoir. I had mentioned that my cap was cracked, but should be able to glue it ok.

This should be plug and play, right? Nope..
The harness on this one is about 12 inches too short.

After checking with Guzziology, I decided to make a longer one. In for a penny, in for a pound, as they say.

While I'm at it, I may as well fix this bodge. Wonder what made the Distinguished Previous Owner think this was a good idea?  ;D

Patience and perseverance saves the day.

My ultra modern heat gun makes short work of the heat shrink tubing..

Woo Hoo! High beam, low beam and flash. Start switch says it'll work. Turnsignals and horn say they'll work, too. ;-T Looks a *lot* better, to boot. Thanks, LeRoy!

 

[balvenie]

Enthralling ;D

[IceBlue]

Chuck
Tube between the front fork leggs seems missing on the second last pic....

[Chuck in Indiana]

Chuck
Tube between the front fork leggs seems missing on the second last pic....

Yep. I thought that disabling it was commonly done?

[IceBlue]

True, some do it. I'm not sure how well it works. I have mine on, and if tight, you can firm up suspension. Not that I think that is needed on the Lario. Stock suspension has that possibility both front and rear. I have stock at the rear too with this option, but may replace it some time.

[Chuck in Indiana]

I think the front is fine. <shrug> I serviced the front and installed new rears before going on our trip. Don't need no steenkin air shocks.. ;D

[kevdog3019]

Those bladders are crap and don't hold a charge anyhow.  Tried fixing mine and it was pointless.  I wouldn't worry about it myself.  You could get Marz. Alluzuras (sp?) like I'm doing on my hopped up Lario.  I'll tell you what that does if when I get it.
-Kevin  

[Chuck in Indiana]

Ok, now that I know the switchgear is going to work, and don't need to replace the switches, clutch and brake perches and levers, and master cylinder <Woo Hoo!> we might as well fill and bleed the brakes.
Here's my re-purposed Cajun Injector (with replaceable o ring) bodge. ;D Suck up enough fluid to get the job done..

Get the air out by putting a paper towel over the end and gently injecting. This keeps a guy from spraying brake fluid all over the shop, not that I've ever done anything like that.. :BEER:

This is a little messy. "Try" to get the hose on the nipple without any air bubbles. Not too fussy, yet, because you are going to push the air bubbles out of the reservoir.
 
With any luck at all, you won't have any air bubbles like this one.  ::) *Don't* let it get into the system. Close the bleed nipple remove the hose, and purge that sucker out of there. This time, it matters not to let any air get in there, a gentle push on the injector as you put the hose back on the nipple (even messier) will do the trick. After you have fluid in the reservoir, close the bleeder and you're probably done.

It had a slightly spongy lever, so clamping the lever back with a big tie wrap and letting it sit overnight will let the micro bubbles percolate out of the master cylinder. Patience can be it's own reward.. ;)


edit to delete a picture

[Chas H]

I think you'll have better results leaving that brake lever at rest. The relief port is closed when the brake is applied keeping fluid- and air-from returning to the reservoir.

[Chuck in Indiana]

I think you'll have better results leaving that brake lever at rest. The relief port is closed when the brake is applied keeping fluid- and air-from returning to the reservoir.

You are right, of course, but my theory is that the bubbles work themselves to the top in the pressurized line. When the lever is released, they go into the master cylinder. I've always done it and it works for me. <shrug>

[Chas H]

You are right, of course, but my theory is that the bubbles work themselves to the top in the pressurized line. When the lever is released, they go into the master cylinder. I've always done it and it works for me. <shrug>

That makes sense.
I have done something similar on car brakes by retracting the brake pads to force fluid, and hopefully that troublesome bubble, back into the reservoir.

[Chuck in Indiana]

24 hours later, you can see the difference from when I originally tie wrapped it down to as hard as I can pull on it, now. The air goes *somewhere*  ;D

[Tazturtle]

Nice one. I used to do the cable tie trick on my 82 1100 Katana. Royal PIA to bleed with the brake fluid controlled fork anti-dive.

Kurt

[Chuck in Indiana]

Nice one. I used to do the cable tie trick on my 82 1100 Katana. Royal PIA to bleed with the brake fluid controlled fork anti-dive.

Kurt

<shrug> For what ever reason.. it works. That was the reason for this thread.. to show newbys what has worked for me, and what's involved with the "barn fresh" find. ;D :BEER:

[Chuck in Indiana]

I've always said that if you look for trouble on an old machine, you'll find it.  ;D I started to put new fluid in the other front caliper, and I couldn't push it into the master cylinder. The only reason for that is that the piston in the master cylinder isn't returning fully. Unhooked fittings, put 100 psi on the end of the m/s, and nada. It wasn't budging. <sigh> Took it off to have a look see.

I've done a fair amount of brake work on airplanes, but many times on Guzzis, when I do something, it's the first time. I rebuilt Rosie's master cylinder, but this one is different, and I didn't see how it came apart. A little research, and had at it. It takes a long punch to drive the piston out to the stop. I had a 3/32" ejector pin from a mold that is about right. A Guzzi spoke will do it, too, I understand. ;D

After the piston bottoms out, turn the whole works upside down, take another special Guzzi Tool, a 14 mm thin wall socket, and give it a swat. Then you can drive the piston out with your spoke, or whatever you have.. ;D

Yech. No doubt, this Lario's brake system has never been serviced in it's life.. probably not unusual, but still..

Looking at this stuff, I cleaned the bore with fear and trepidation. It's obviously had water in it, and it could be toast. $150.  :o Fortunately, it's ok, so a $29 rebuild kit will fix it up. Time to get on the horn and order a kit, and a few other things while I'm at it. I mentioned in the first post the the most expensive bike you can buy is the cheapest, because someone else has already spent the money on it. Remember?  ;D That's ok, this is fun for me.

I believe that was the 5 o'clock whistle, a little celebration is in order.  ;D

Might be a few days before parts get here, so I need to do something else. After all, if there wasn't something to do, it wouldn't be much of a Winter project, would it?

[Morizzi]

Hi Chuck,

I've had issues with sticking pistons before. Mine haven't been water affected but the seals have swolen, probably due to incorrect fluid being used by a PO.

I've always managed to get them to work.

DOT 3 is more slippery than DOT 4. It isn't as heat resistant and should be changed a bit more regularly but it works fine for a road bike. Doesn't affect any type of seal I'm aware of either.

On a really reluctant Grimeca rear M/C on the Morini I fitted a smaller inner spring that did the trick for the piston return. It has a left hand foot brake so I can't meter out the pressure evenly anyway. Simply a coordination issue as I'm right handed. A bit more resistance helps me to not overdo the rear braking. Most of the time I'm better off forgeting it even exists.  :D

Cheers

Rod

[Chuck in Indiana]

changed a bit more regularly

You mean that once in 25 years isn't enough?  ;D :BEER:

[Trevor G]

True, some do it. I'm not sure how well it works. I have mine on, and if tight, you can firm up suspension. Not that I think that is needed on the Lario. Stock suspension has that possibility both front and rear. I have stock at the rear too with this option, but may replace it some time.

The air is simply a spring assist, to stiffen up the spring rate and increase the front ride height.

I don't think it's at all necessary to do that!

Instead, I compress the forks and pop the air valve to release excess air.  This lowers the front end which makes it a little quicker when turning into a corner.

Since the seals are not great I have to do that every time I ride, but it's not a problem.

[Chas H]

Hi Chuck,

I've had issues with sticking pistons before. Mine haven't been water affected but the seals have swolen, probably due to incorrect fluid being used by a PO.

I've always managed to get them to work.

DOT 3 is more slippery than DOT 4. It isn't as heat resistant and should be changed a bit more regularly but it works fine for a road bike. Doesn't affect any type of seal I'm aware of either.

On a really reluctant Grimeca rear M/C on the Morini I fitted a smaller inner spring that did the trick for the piston return. It has a left hand foot brake so I can't meter out the pressure evenly anyway. Simply a coordination issue as I'm right handed. A bit more resistance helps me to not overdo the rear braking. Most of the time I'm better off forgeting it even exists.  :D

Cheers

Rod

DOT 4 for the most part has a higher boiling point than DOT 3, but will absorb moisture quicker-which lowers the boiling point.
In cars, it is recommended to change DOT 4 fluid on a shorter interval than DOT 3 because of the water absorbtion. I use the fluid and change according to the maker's specs.

[Chuck in Indiana]

Looking out the window this morning, I see 2 inches of fresh snow. I used to dislike winter because I had to get out in it. Now, all I have to do is walk back to the shop and play with the Lario.  ;D Life is good...

Many years ago, when I was building street rods, I was scrounging parts at a guy's place and saw this stainless steel sink/counter top laying in his junk pile. The light came on, and I realized it would be the perfect engine building "taco wagon." Simple to clean, etc. "Disposed " of it for him, built it with scrap lumber (free, Guzzi content) but actually had to buy the wheels.  ;D I've built many engines on it over the years.  ;-T So I rolled it into the shop this morning, and stored the airplane junk that it had accumulated.

My son Brad (Guzzi guy and helicopter mechanic, I brought him up right..) told me to get some of this stuff. I'd always used Stoddard solvent and a high pressure air gun to degrease stuff, but he knows what he is doing and I gave it a try.

It did a remarkable job of degreasing the top, and cleans up with water. When I asked Brad how good a job it did, he said you could paint over it. (!!) Hmmm.
Ok, lets get this drivetrain out of it. Build a sturdy box 8 1/2" tall, lift the front (small blocks don't weigh much) and slide it under the pan. Pick up the rear and slide a 2 by 4 under the rear tire. For you metric guys, a 'Merican 2 by 4 is actually 1 3/4" tall. These dimensions are "just right" and lets everything come apart without issue, including tearing the drive shaft boot if the rear wheel goes too far down when you remove the rear shocks. Don't ask me how I know.  ;)

Unhook the rear shocks and tie up the rear brake caliper..

There is one bolt on each side of the frame and a through bolt on the transmission..

Tap the through bolt with a brass drift.
Then drive the bolt out with an undersized pin. I was a mold maker in another lifetime, and have *lots* of hardend ground ejector pins, perfect for this job.

This keeps everything aligned while you unhook the 4 frame bolts in front.

Now, it's ready to come apart, but I hear the lunch whistle blowing. Don't touch that dial! We'll be back in a moment. Well, that's what the tv guy used to say when the program was getting exciting.. ;D :BEER:

[kevdog3019]

 :pop  :BEER:

[Tobit]

Great thread.  About the rear master cylinder, the stuck piston problem you ran into once happened to me.  The first time I bled the brakes on my LeMans IV, a few years after purchase  ;D, I did it by the old open-the-bleeder-and-pump-the-pedal method.  Not only did that not work, the first pump stroked the piston down to never-never-been-this-far-before land where it got stuck in the old marinera sauce.

After a rebuild I learned to bleed as you did, from the caliper and also made a nifty cover for the front end of the master cylinder from some old rubber bit I had laying around.

 ;-T

[Chuck in Indiana]

Great thread.  About the rear master cylinder, the stuck piston problem you ran into once happened to me.  The first time I bled the brakes on my LeMans IV, a few years after purchase  ;D, I did it by the old open-the-bleeder-and-pump-the-pedal method.  Not only did that not work, the first pump stroked the piston down to never-never-been-this-far-before land where it got stuck in the old marinera sauce.

After a rebuild I learned to bleed as you did, from the caliper and also made a nifty cover for the front end of the master cylinder from some old rubber bit I had laying around.

 ;-T

 ;D I know what you're talking about..

[Chuck in Indiana]

Alrighty, back from lunch. Just pick up the back, hold the handlebar, and wheelbarrow it away. Have a saw horse waiting or you may end up laying it on it's side.. ;D How long did this all take? Considerably less than telling about it.

Here's what's left. A small block is considerably easier to work on than a big block, IMHO.

Beautiful motive unit, isn't it? A really elegant engineering solution. I love Guzzis.. ;-T

Ok, enough looking at it, get to work. Loosen the HOSE CLAMP (Guzzi content) on the boot..

Remove the rear wheel and rear drive. Take off the jam nuts (the big chrome ones) on the swing arm, and *carefully* remove the special fasteners that fit into the swing arm bearings. Some AeroQroil or your favorite spooge here is a plus.

These are delicate threads, pay attention.  ;D

Keep track of this washer on the D side. It's important on reassembly.

Here is the exploded view of the driveshaft assembly. It looks good, and the U joint appears to be rebuildable.

A C ring holds the driveshaft boot in the casting..

A short piece of aircraft 4130 bushing stock out of my "good junk" box holds the drive box together for clean up and paint. Drive splines look ok.

Spritzing some of Brad's cleaner on the swing arm and wiping it off with a paper towel is really impressive.  ;-T I guess the boy knows what he's talking about.  ;D

Knocking off early today, time to clean up and organize tools. Next will be the grunt work..cleaning and prepping.