Author Topic: 750S The Build is Done  (Read 67977 times)

canuck750

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Re: 750S Rebuild merged
« Reply #60 on: March 05, 2016, 11:31:48 PM »
Hi Shaun

I spoke with Colt last week, they were OK sending my cam direct, I mailed it off last week. I dropped my crank off at the machine shop on Thursday, it needs 1st over cuts on the mains. Hopefully I can get the engine back together in a couple weeks. I would like to ride the 750S this summer!

Offline smdl

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Re: 750S Rebuild merged
« Reply #61 on: March 06, 2016, 11:30:29 AM »
Glad it worked out.

Cheers,
Shaun
'74 Eldorado Police
'74 Eldorado Civilian
'75 850-T
'12 Stelvio NTX
'20 V85 TT

'71 Honda CB175 Super Sport
'10 Kawasaki Ninja 250

canuck750

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Re: 750S Rebuild merged
« Reply #62 on: March 08, 2016, 07:34:02 PM »
Colt Cams called yesterday to tell me the cam I sent is not stock, it has no marks and does not match any Guzzi specs, HMB confirmed that the specs Colt gave me is that its a custom cam, lots of intake lift 330thou and 280 for the exhaust, HMB does not care for the profile, neither do Colt. I probably need to fork out for a new cam.

Small progress back in the garage, rear brakes. I had the cam pivots replated and soda blasted the back plate



My home made shoe spreader has come in very handy over the years



One shoe had a blob on the casting, neede to grind it round to fit the back plate pin



A pair of new springs and that's done



I took the frame and swing arm in for powder coating and the T3 lower triple and stem came in from Harpers today,

Thanks Curtis!

Online Antietam Classic Cycle

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Re: 750S Rebuild merged
« Reply #63 on: March 08, 2016, 08:36:12 PM »
Colt Cams called yesterday to tell me the cam I sent is not stock, it has no marks and does not match any Guzzi specs, HMB confirmed that the specs Colt gave me is that its a custom cam, lots of intake lift 330thou and 280 for the exhaust, HMB does not care for the profile, neither do Colt. I probably need to fork out for a new cam.

As I mentioned before, Delta Camshaft has specs. for all the Guzzi cams and can grind whatever you send them to whatever spec. you desire. Worth checking out.
Charlie
http://www.AntietamClassicCycle.com
'69 V700
'69 Ambassador
'71 Ambassador
'73 Eldorado
'74 850-T
'76 Convert
'77 Morini 3 1/2 Strada
'81 Ducati 500SL Pantah
'82 V50 III

Wildgoose Chase Moto Guzzi

Re: 750S Rebuild merged
« Reply #63 on: March 08, 2016, 08:36:12 PM »

canuck750

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Re: 750S Rebuild merged
« Reply #64 on: March 08, 2016, 10:22:34 PM »
As I mentioned before, Delta Camshaft has specs. for all the Guzzi cams and can grind whatever you send them to whatever spec. you desire. Worth checking out.

Thanks Charlie, Colt grinds the cams for MG Cycle and they have all the factory Guzzi specs. Apparently the cam I sent to Colt has profiles such that there is insufficient hardened steel to cut the B10 profile. This is what HMB was able to tell me based upon the measurements from Colt:

 "surely this is no stock cam. Asymmetrical lift was only done by Bruno Scola, his cams are known to be noisy and not very long lasting.
 Missing marks are a second sign for it not being a stock cam.
 And, it could have been  ground from a P3 cam, as the P3 base a larger base circle."

The 750S I am rebuilding was a wreck survivor and the previous owner must have been experimenting with horse power before the bike was passed on and ended up here in Canada.

I think I need to go look for a B10.

canuck750

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Re: 750S Rebuild merged
« Reply #65 on: March 10, 2016, 08:15:27 PM »
The 750 S uses a grey plastic CEV fuse box, hard to find in the correct colour. CEV fuse boxes were also used on the Benelli 650 and Moto-Morini 3 1/2.

I found a decent Beneli fuse box but it does not have the same number of fuse holders so I made some from .030 brass strips.

I drill out the rivets on the bask to remove the clear cover then drill out all the rivets holding the brass strips. Clean all the corrosion off the original brass strips.



I bought a 6" shear being cleared out for under $50.00 a piece, great deal



Then made replica strips

























Powder coating finished today, engine next



canuck750

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Re: 750S Rebuild merged
« Reply #66 on: March 15, 2016, 10:05:42 PM »
Waiting on the crank grind, I can get some small stuff back together, easier to install some of the electrical before the engine joins the frame.

Gregory Bender supplied a complete wire harness with all the sub-harness items.



I found that installing the high tension leads into the coils prior to mounting them is much easier to do than trying to twist the wire into the coil mounted on the frame.



And fitting the rectifier, regulator and the wire terminal block is straight forward when there is room fit hands into the tight spaces



And the lower triple is repaired thanks to Harper's supplying a new stem, the repro damper rod comes with a nice stainless steel base plate



This is my therapy and returning old bikes to the street drops my blood pressure like nothing else.

Offline nobleswood

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Re: 750S Rebuild merged
« Reply #67 on: March 16, 2016, 07:03:13 AM »
 :bow:   :popcorn:
2004 V11 Sport Naked / Ballabio
2013 1200 8v Griso

Offline Rick4003

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Re: 750S Rebuild merged
« Reply #68 on: March 16, 2016, 07:21:15 AM »
  :1:
:bow:   :popcorn:

You have really shown how great it is to be able to powder coat at home! I have to get me one of those guns!  :grin:

And amazing job as usual!
Moto Guzzi 850 T5 (850 sport) - 1985
Moto Guzzi Ambassador - 1967
Yamaha FZR 600 - 1996 - SOLD

canuck750

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Re: 750S Rebuild merged
« Reply #69 on: March 16, 2016, 06:26:50 PM »
For $149.00 Eastwood Automotive supplies a complete kit, powder gun, sample powders, and silicone plugs.

http://www.eastwood.com/powder-gun-promo-kit.html

Or this one for $70.00 at Harbor Freight, and Harbour freight stocks a few colours of powder.

http://www.harborfreight.com/10-30-psi-powder-coating-system-94244.html

High heat masking tape is handy

http://www.eastwood.com/high-temp-fiberglass-masking-tape.html

You will need a clean and dry source of compressed air, only 2 ~ 5 lbs pressure, a small cheap regulator attached to your powder gun works great.

For baking look for a large used toaster oven, if you have the room get a hold of an old surplus wall mounted oven, I have found two for free over the years by searching the local small adds, people are always renovating kitchens and usually the owner just wants to get rid of the oven.

An infrared thermometer is handy to gauge the temperature of your parts as they cure in the oven, most powder is cured at 375 degrees F.

$34.00 from Harbor Freight.

http://www.harborfreight.com/non-contact-infrared-thermometer-with-laser-targeting-61894.html

Your parts need to be clean, rust free, all old paint removed. A wire wheel in a bench grinder does wonders.

Prior to spraying the powder I wash the parts with acetone.

I lay a sheet of thin polyethylene on the garage floor and up the overhead door, taped to the overhead door. Then I set up a step ladder to one side and fit a length of steel tube from the ladder step to hang the parts off to powder coat. I hang the parts from stainless steel wire that I then transfer the parts to the oven to let the powder cure. The parts hang from the top rack in the oven.

I pull up the plastic with the loose powder and throw it all in the garbage when done.

Clean up is just sweeping up the residue powder

It is so easy and mess free that once you get started you will not go back to rattle cans again.





Offline balvenie

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Re: 750S Rebuild merged
« Reply #70 on: March 16, 2016, 06:39:17 PM »
Beautiful :grin:
Oz
04 Cali
As ye practice, so do ye teach.

canuck750

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Re: 750S Rebuild merged
« Reply #71 on: March 16, 2016, 10:32:55 PM »
Like the old saying goes you learn something new every day, fitting the triple clamps and forks I go looking for the ignition switch lock plate that fits beneath the upper triple clamp... except there isn't one with this bike.

The 750S being a 1974 model (V7Sport in North America), the steering lock is reported to be identical to the V7 Sport using the ignition switch drop pin as the lock. But on this bike there is a frame mounted steering lock like the 850T and later Tonti frame bikes. The serial number stamped into the frame is clearly a 750S and the underside of the triple has the indent to take the lock plate. So to reduce the gap between the top of the upper bearing cap and the triple I made up a spacer equal in thickness to the lock plate.



In go the forks, the swan necks and the head light brackets



A few more bits and pieces back together, if I squint it's starting to resemble a motorcycle, well maybe not yet.....



canuck750

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Re: 750S Rebuild merged
« Reply #72 on: March 17, 2016, 09:52:03 PM »
The machine shop called to say the crank grind is done, perfect!

I am lucky to have such a great machine shop in my town, these guys build race engines and have been at it for decades



And they balanced the rods too



Swap out the oil tubes from  he old bearings





Lock a new sludge trap plug into the crank



Fit the new front bearing, torque down the six bolts and lock the tabs over the bolts



Fit a new rear main gasket with just a trace of sealant on the bottom half, heat up the block and fit two studs in to guide the bearing in



Then tabs,, torque the bolts and thread sealant on the two bottom bolts





A new rear seal oiled up and then pressed in with a special tool



Fit the breather pipes



Fitted new shells, rod bolts and nuts and then torque in the rods





And the new B10 cam came in the mail today from John, thanks mate!



Hopefully the heads will be ready by Saturday and I can button the engine up this weekend.


Offline balvenie

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Re: 750S Rebuild merged
« Reply #73 on: March 17, 2016, 10:08:39 PM »
Love it. You could sell tickets :grin:
Oz
04 Cali
As ye practice, so do ye teach.

canuck750

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Re: 750S Rebuild merged
« Reply #74 on: March 17, 2016, 10:19:11 PM »
Love it. You could sell tickets :grin:

Glad to share my gearhead porn!

If anyone has a NEW oil pump for sale to fit a V7 Sport / Eldorado please send me a pm, I am having a tough time finding one 4 sale.

PS - Some on-line venders advertise the 750S oil pump as being equal to the T3 but the 750S is the same as the V7 Sport.

Offline ailgev

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Re: 750S Rebuild merged
« Reply #75 on: March 20, 2016, 05:54:42 PM »
Hey Jim,

Love your work and detail.
I just noticed on your gearbox that a couple of he bearings you have installed from the HMB kit look like they have polymid cages.
I recently bought a N303 bearing from HMB and received the same one (polymid caged).
Im not sure if Im going to use it as I removed a couple which had cracked plastic cages and the balls were about to let loose in the box.
Michael says that the polymid are different than original plastic caged ones Guzzi used and are better than the steel caged ones.

Are these ones different than the original plastic caged bearings do you know?

Paul.

Offline smdl

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Re: 750S Rebuild merged
« Reply #76 on: March 20, 2016, 06:00:54 PM »
Fantastic work, Jim!  I'm really enjoying this one.

My progress is slower, but there is some.  Will have another update soon.

Cheers,
Shaun
« Last Edit: March 20, 2016, 06:01:23 PM by smdl »
'74 Eldorado Police
'74 Eldorado Civilian
'75 850-T
'12 Stelvio NTX
'20 V85 TT

'71 Honda CB175 Super Sport
'10 Kawasaki Ninja 250

canuck750

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Re: 750S Rebuild merged
« Reply #77 on: March 20, 2016, 06:44:07 PM »
Hey Jim,

Love your work and detail.
I just noticed on your gearbox that a couple of he bearings you have installed from the HMB kit look like they have polymid cages.
I recently bought a N303 bearing from HMB and received the same one (polymid caged).
Im not sure if Im going to use it as I removed a couple which had cracked plastic cages and the balls were about to let loose in the box.
Michael says that the polymid are different than original plastic caged ones Guzzi used and are better than the steel caged ones.

Are these ones different than the original plastic caged bearings do you know?

Paul.

Hi Paul,

I was disappointed to find the bearings had the polymer cages, HMB assured me these new bearings are top quality and not the same as the earlier plastic caged bearings, I am trusting the experts on this one.

canuck750

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Re: 750S Rebuild merged
« Reply #78 on: March 20, 2016, 07:02:08 PM »
Fantastic work, Jim!  I'm really enjoying this one.

My progress is slower, but there is some.  Will have another update soon.

Cheers,
Shaun

Any progress is still progress! Your 750S tribute is going to be a very cool bike!

I spent most of the weekend in the office, damn work keeps getting in the way of important things, like engine assembly,

I got a couple hours in this afternoon,

Stripped and cleaned the oil delivery pipe and pressure release valve



My home made pressure tester indicates valve opening at just over 55 psi, within spec so that's good



I re-measured the oil pump.one shaft is good, the other one is just a couple thou under so due to no new ones available I am going to use this one and fit a pressure gauge, worst case I will need to replace it but |I can do that with the engine in the frame, I used a liberal pasting of assembly lube on everything that rotates



In goes the pump. pick up screen and oil tube





I salvaged all the sheet steel tabs and had them zinc plated



Bend over and peen the lock tabs



I measured the cam I got in the mail this week, it checks out to be a B-10, consistent lift on all 4 lobes, a coating of assembly lube



Some locktite and shnoor wwashers



Cam is back in with a new thrust bearing



Alloy gear set goes back on with new hardware



A brass rod machined to the small end bush diameter safely hold the crank in place and the special tool is bolted tight to the crank shaft end



Torque the crank nut on and bend over the lock tab

Then fit the cam sprocket, align the marks, hold the crank steady and torque the cam shaft nut



Lube the cam followers and drop them into the block





Install new base gaskets and O rings at 6 and 12 o'clock



Heat the pistons, fit the pins to the rods and install new clips



Oil the piston and rings, Compress the rings



Drop the cylinders on



That's all for now, waiting on heads to come back from the machine shop





Offline balvenie

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Re: 750S Rebuild merged
« Reply #79 on: March 20, 2016, 10:42:06 PM »
Great :grin:
Oz
04 Cali
As ye practice, so do ye teach.

canuck750

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Re: 750S Rebuild merged
« Reply #80 on: March 24, 2016, 07:30:01 PM »
Working on these old machines with an unclear history, previously modified, rebuilt etc, can be very confusing, it's a bit of archeology and some detective work. The 750S, at least the engine in this one did not come with an oil filter, the engine appears to be identical to the V7 Sport engines I have rebuilt. Some literature claims that the 750S came with a timing chain as opposed to gears, this is plausible for this motor as it now wears aluminum timing gears and no chain. All of that said, the oil pump in the V7 Sport is the same as the Eldorado and I assumed that this motor would use the same non oil filter pump.

I could not find a new V7 Sport / Eldorado pump for sale so opted to risk reinstalling the slightly worn original. After I reinstalled the original pump I realized it is not the same as the ones in the V7 Sport. I found it mnatches this one, designed for the 850 T3 an onward.

http://hmb-guzzi.de/Oil-Pump-Cali-1100-V11-etc

So I have ordered one of these to fit into the 750S and now I am questioning if the oil pump I have in the 750S motor is correct? Perhaps it is or maybe the previous owner installed this later model oil pump along with the timing gear set and Giladorni pistons when the bike was rebuilt in the 90's.

If anyone can verify what is the correct pump for the 750S and more importantly is there any problem using this 850T3 type pump in a non oil filter engine????

PS, thanks to Dick for sending me a shift drum detent and spring, Guzzi people are fantastic!

Online Antietam Classic Cycle

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Re: 750S Rebuild merged
« Reply #81 on: March 24, 2016, 08:17:07 PM »
If anyone can verify what is the correct pump for the 750S and more importantly is there any problem using this 850T3 type pump in a non oil filter engine????

I used this pump:
http://www.mgcycle.com/index.php?main_page=product_info&cPath=68_162&products_id=1985
in a non-filter Eldo engine, works perfectly. Don't know if that helps?
Charlie
http://www.AntietamClassicCycle.com
'69 V700
'69 Ambassador
'71 Ambassador
'73 Eldorado
'74 850-T
'76 Convert
'77 Morini 3 1/2 Strada
'81 Ducati 500SL Pantah
'82 V50 III

canuck750

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Re: 750S Rebuild merged
« Reply #82 on: March 24, 2016, 08:20:19 PM »
Thanks Charlie!

It's good to know using this type of pump will function properly in a non filter engine.

Jim

canuck750

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Re: 750S Rebuild merged
« Reply #83 on: March 26, 2016, 06:39:02 PM »
waiting on parts again I stripped the chrome steel rims that the bike came with when I got it, (I have replaced the rims with the correct Borrani aluminum wheels), this is what lies beneath that shiny chrome rim



The corrosion is very deep in many places, junk rims that on the outside looked pretty good!



Even the front one that had a pretty new looking tire has its spots of rot



From the receipts that came with the bike these chrome steel rims were installed in the mid 90's and as was evident by so many other tell tale signs during the disassembly this poor unloved beast spent many a night out in the damp and probably salt air.

Even after some cleaning with a ire brush the rot only goes deeper



Moral of the story is old steel rims, even if they look OK should be inspected, the alternative could be disastrous on the road at speed!





canuck750

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Re: 750S Rebuild merged
« Reply #84 on: April 11, 2016, 10:09:12 PM »
I broke down and bought a new oil pump, having gone in so deep once again I just couldn't leave a borderline part in the engine. The new one came in today so I swapped the new one in.



The machine shop finished the head rebuild today, new valves, springs, valve grind.



Some new hardware and O rings and the heads are back on







Pan back in place



and some new hoses, crush washers and clamps



now just to check the timing with a degree wheel and assemble the flywheel and clutch

Next is a diversion back to my Eldorado, still a slow oil leak out the back of the engine from the bellhousing, I am guessing the oil vent tube sealing washers are not, sealing that is, probably 50 cents in parts and an 8 hour job to pull the transmission, clutch etc to find that damn little leak, I lived with it all last year but it's time to do try and get it solved once and for all.


Offline Air-Cooled

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Re: 750S Rebuild merged
« Reply #85 on: April 12, 2016, 12:01:26 AM »
I seem to recall that Mick Walker's book on Guzzi stated that all 750S bikes were chain, no more gears after the V7 Sport and Eldorado.
'73 V7 Sport, '16 Stornello, '15 Harley Ultra Classic, '14 Harley Wide Glide, '97 Honda XR600R

canuck750

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Re: 750S Rebuild merged
« Reply #86 on: April 13, 2016, 09:54:29 PM »
I seem to recall that Mick Walker's book on Guzzi stated that all 750S bikes were chain, no more gears after the V7 Sport and Eldorado.

I recall reading the same thing, these are aluminum cam and oil pump gears, the crank gear is steel.

I moved the engine over to the lift but first I bolted the engine stand down to the lift, almost tipped the last one over by mistaje and I don't need to risk that again.

Fitting the flywheel, I remembered to paint the end of the crank and flywheel before disassembly to be sure I reinstalled the flywheel in the correct position



New lock tabs and bolts and some locktite then torque it down to the crank

I don't know if this is good practice but I glued the clutch springs into the flywheel to keep them in position



Then fitted the clutch components





and then the plug



and that's done


canuck750

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Re: 750S Rebuild merged
« Reply #87 on: April 23, 2016, 12:30:12 PM »
As I have stated many times, 'I an not a mechanic', more of a parts replacer with a lot of tools and the audacity to plow into anything that makes up a motorcycle.

The preface of this update is to admit to another lesson learned, albeit the hard way, ...again, ...which is my usual means of education :cry:.

After assembling the engine, clutch, mating the transmission and fitting the valve gear I was checking the valve timing with a dial gauge to verify intake opening as per the factory specs. Now the crank has been rotating as smooth as could be expected with a fresh grind and new bearings and big end shells, spins effortlessly with the heads off. The cam is opening the intake at the right time as measured by a degree wheel and verified by a dial gauge. All is well as I spin the crank with a hex head socket into the rotor bolt... and then its starts to get stiffer, very, very stiff and then the crank shaft just locks up.

hmmm, this is strange, removed the rockers and push rods, no better, still the crank shaft will not rotate. Separate the transmission, still no change. Remove the clutch / flywheel nothing.

Ok so its back to stripping the motor, timing gears removed, no change, cam spins, oil pump spins... crank is stuck.

Remove the pistons and rods, nothing that leaves one or both of the main bearings.

Pulled the rear bearing nope still stuck, damn it's the front main bearing.

I had to use a block of wood and some gentle persuasion to separate crank from bearing and the soft main bearing is ruined. A residue of soft white metal needs to be polished of the front of the crank.

Sorry for the long winded report, but the conclusion is I had not checked if the crank shaft oil passage openings had been chamfered after grinding and not leaving a sharp edge to catch on a bearing, which appears to be the cause to the instantaneous destruction of the front main bearing from a couple of rotations by hand. Had I attempted to start the engine I am sure the result would have been a seizure and soft white metal strewn all about the internals of the motor. It will cost me a new front main bearing and a couple days to put it all back together and set the timing, clutch, etc, back up.

Now to take a good look at the crank oil passage openings and make sure the edges of the openings have no burrs or ridges.

And that is my lesson for the week. :violent1:




Offline smdl

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Re: 750S Rebuild merged
« Reply #88 on: April 23, 2016, 12:52:22 PM »
Ugh!  Sorry to hear it, Jim.  I can fully appreciate the whole "learning motorcycle mechanics through (painful) experience" thing.  Oh, well, your future builds will be that much better for having learned this valuable lesson.

My recent lesson was not to be an idiot and slip/fall on the very last really cold day of the year, and just before real riding weather starts.  Your issue is much more forgivable!   :grin:

Cheers,
Shaun
'74 Eldorado Police
'74 Eldorado Civilian
'75 850-T
'12 Stelvio NTX
'20 V85 TT

'71 Honda CB175 Super Sport
'10 Kawasaki Ninja 250

canuck750

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Re: 750S Rebuild merged
« Reply #89 on: April 24, 2016, 07:55:44 PM »
I hope you are mending well Shaun, summer is just around the corner time to ride.

I crabbed my Eldorado today and pulled the transmission to locate the slow steady drip of engine oil out the bottom of the bellhousing, looks like the breather tube crush washers were not sealing. In the process of pulling the tranny I had to remove the header pipes but one of the threaded exhaust header clamps is seized, probably cross threaded as it turned with much resistance but is now stuck, I had to remove the head with the header as a unit to tip the motor forward. Why is it that every small job, in this case a couple of cheap crush washers leads to a potential head replacement and who knows what else??

I need to lock the head in a vice and try to get the header clamp off without wrecking the head threads, any ideas?

Cheers
Jim

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