Mitch's 72 Engine Rebuild

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I would send cam followers to Megacycle and have them resurfaced. Keep them wired together in pairs, and mark/etch/I.D. them internally L1, L2 and R1, R2.
 
grandpaul said:
Keep them wired together in pairs, and mark/etch/I.D. them internally L1, L2 and R1, R2.
Click to expand...
L, L and R, R will do, unless you fit them 180 degrees wrong :wink:
Give your barrel a slight running in/cleaning hone and get rid of the cylinderbase gasket (tighter joint and stays tight).
 
I thought you would resurface them on the floor like you do your clutch plate's!!

grandpaul said:
I would send cam followers to Megacycle and have them resurfaced.
Click to expand...
 
bill said:
I thought you would resurface them on the floor like you do your clutch plate's!!

grandpaul said:
I would send cam followers to Megacycle and have them resurfaced.
Click to expand...
Click to expand...

Nope, cam followers have a much more precise tolerance.

Definitely more precise than certain "fabrication" operations I've personally seen.
 
More pictures of the pistons. Definitely the short slot type.
Hard to see in this photo but there is a vertical gouge below the pin boss and several on the lower left side.
Mitch's 72 Engine Rebuild

There are also vertical gouges around the crown about 2/3 of the way around.
Mitch's 72 Engine Rebuild

Not sure what caused them. Looks almost like someone tried to force the oil ring expander down.
Here's the markings on the inside
Mitch's 72 Engine Rebuild

Mitch's 72 Engine Rebuild
 
Torontonian said:
I'm not there to inspect but things look acceptable. My 72 uses those pistons and I wail about on them all day, standard bore original ,very little oil consumption,carefull assembly of ring positions helped.Cam and lifters look acceptable but there are others who would disagree I'm sure. Just for fun using a flashlight look for the bronze cam retaining washers with bent over tabs into timing case hole for locating purposes. These have microcracks at tab bendover points that can fail or not. Going to split the cases to clean out the sludgetrap I assume ?
Click to expand...


Here's a long slot piston I unfortunately used in a 72 Combat:

Mitch's 72 Engine Rebuild
 
htown16 said:
Opinions on all the gouges, trash em or use em?
Click to expand...
use em (or trash em to me) Not sure about the piston rings, close up picture?!
 
They are unsatisfactory unless youre severely financially constrained .

Theres Hepolite & Norton pistons around for $ 200 a piar , std bore .

Fitting youres theyll need premature replacement , unless theres a bump in the bore from where the rings stuck ,
you might get a bit of milage out of the , and rebore at 20.000 for new pistons .
 
Ordered some new pistons and rings for this engine. Will clean these up and save them for a beater project I am also building.
 
Got the new pistons and rings in along with a set of Black Diamond valves and bronze guides. Right now I am stripping the timing side so I can split the cases. I had a helluv a time getting the cam nut off. Heat, penetrating oil and a lot of effort finally got it to come off. Now the oil pump worm drive won't unscrew from the end of the crank, yes I know it is LH thread. I'm suspicious maybe someone used red loctite on these. It looks like the timing cover has been off as it now has allen screws. How much heat should I use on the end of the crank? I'm using a MAP bottle. Any other ideas?
 
An air impact wrench should be able to knock that crank nut off in short order. Build up the line pressure to the max before hitting it. You have to secure the crank from turning...
 
Bought an electric impact wrench at Northern Tool. Zipped it right off. Went to use the puller I bought on the crank pinon gear and it won't fit behind the gear. Looks like a little grinding on the puller ears may be needed.
 
The crank pinion puller is specific for the job (works on Nortons and Triumphs), 3 wide, curved jaws in a narrow diameter aperature that JUST slips in place. If you don't have the triangular spacer underneath the pinion, you have a problem!
 
Had to grind a little additional chamfer into the outside edges of the puller ears to get the puller to fit down around the pinion then popped right off. Cases came apart with no problem.
Here's a picture of the cam, no obvious problems that I can see. Has scrolls, so must be post combat, 1973 type. Standard grind?
Mitch's 72 Engine Rebuild

Cam bushing, Has slots cut.
Mitch's 72 Engine Rebuild

Tab washer showing fatigue cracks. Both the inner and outer ones are like this.
Mitch's 72 Engine Rebuild

From what I have gathered on here these tabs need to be clipped off?
 
htown16 said:
Tab washer showing fatigue cracks. Both the inner and outer ones are like this. From what I have gathered on here these tabs need to be clipped off?
Click to expand...

Just order the new ones without the tabs.
 
I have had 2 s cam's with and without the scroll. does you cam have 2 S's on it ??? usually in the center of the shaft. I prefer to not use the washer ( tab or not ) and change the cam bush to the 850 style and as you have a scrolled came it makes it simpler.
 
No 2s markings on the cam. Are you talking about the 2 shouldered bushes that replace the one piece timing side bush, pn 06-5428? Do you still use the steel chamfered washer against the tach drive gear with these? I am assuming because the cam is scrolled they don't need to be grooved. Do they need to aligned bored with the drive side bush?
 
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