My What Am I Getting Myself Into Combat Build Thread

So got the case all sealed up, then found these. Wonder where they go?

IMG_2849sm.jpg
 
Don't worry about it, its only 'nut and bolts.

Split the cases (no big deal) and do a 'Take two.
 
Yep. Split the cases, installed the studs and cam washer, cleaned the sealer, resealed and bolted back up. I then realized i had the CNW bolt kit for the case which replaces the studs with bolts. First reaction is i have to re-split the case if i want to change out the studs with the bolts :oops:. Then my mind cleared up and i realized i could just unscrew the studs using the portion that protrudes from the case. Whew.

Ok, back on track. Next up is attaching the barrels. I thought Jim Comstock's method of placing the pistons in the barrels and then attaching the pistons to the connecting rods with the barrel suspended on sockets over the crankcase was the way to go versus the more traditional method of attaching the pistons to the rods and then trying to get the rings from both pistons into the cylinder bores. The only downside with Jim's approach is tying to get the wrist pin clips in with the barrel on top of the rods, especially aftermarket clips in short skirted pistons. I placed some paper towels in the case in case the clip were to fall so they wouldn't fall in the case and proceeded to attach the clips. I previously installed the clips on the inboard side of the pistons so all i had to attach in-situ were the outboard clips. I got one clip in so i'm feeling pretty good. However, the next one was when everything went to hell. My son was helping me and was holding the barrel when i was pushing the clip in. Well i was pushing pretty hard (those clips are a bitch) and pushed the barrel off the sockets. My son, with reflex reaction, went to catch the barrel (not knowing it wasn't really going anywhere because one of the connecting rods was attached) and in doing so also pulled enough of the paper towel to allow the clip, which by now fell out, to fall in the case :eek:

F*#@K

So i pulled the barrel off the one connected piston so i could see if i could see the clip in the case. I couldn't. Next step was to place the case on the side and gently tap it to see if the clip would moved to where i could see it. Nope. Crap! Do i have to re-split the case again to get the effer out? Luckily, I remembered i had a boroscope so i put that into action to see if i could find it. Sure enough

IMG_0002sm.jpg


Looks like it's stuck pretty good in oil/sealant

I tried banging it on it's side, but it didn't budge. So, I cut off a piece of a wire coat hanger and using the boroscope i was able to push it enough from out under the flywheel so i could get to it with a long set of needle noose pliers. Whew!

So with the barrel off and one piston connected to the connecting rod, do i pull that out and go back to step one with trying to get those damned clips installed in situ, or do i forgo the Comstock method and use the more traditional approach of attaching the pistons to the rods first and then attaching the barrel. I decided to go the later route. I also read that the rings could be pushed in the bores with your fingers. It seemed i needed four hands to get the rings in on one piston, let alone two. I gave it a try though but it seemed i was squeezing a ballon. When i pushed on one side, the rings would pop out on the other side. I ended up giving up on this approach and pulled out some old hose clamps to use as ring compressors. I made sure that when tighted down, they rotated freely (i.e. none of the rings were somehow not in their grooves). Still though, you don't know if the ring may bend when sliding in the bores. After i got them in, i rotated the assembely and it didn't seem like there was anything amiss with the rings, so i hope i'm good. Oh, and the gaps are supposed to be orientated in a certain way. That went out the window in all of this. And i used sealant on the base, not a gasket, so by this point i had sealant all over the place. All in all, this entire process was a pain in the butt.

Barrel on!

IMG_2844sm.jpg
 
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I applaud you airing your mistakes/misfortunes so publicly. As the saying goes: 'Those who have never done anything wrong have probably never done anything'

As someone who has just this morning fitted a new bicycle chain successfully on the third attempt, I'm sure the feeling of smug satisfaction when it eventually goes right makes the learning curve (however steep) worth it :)
(Mind you, did manage to replace a broken nut on a 12 string acoustic without the aid of a spanner... And keep the same strings on!)
 
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Tom,

If all goes well, you won't ever have to do it again. If you can get the motor in the frame with the head on, put it on. Putting the head on in the frame like I have to is a real class A PITA.

I'm doing my motor for the 4th time, but I did not want to because of the PITA factor. Jim's parts made me do it. Plus, it's my last motor and I want to use my tools before my body parts don't work so good anymore.

You might want to put some tape over that tach drive hole.
 
If I might.. ( I'm not trying to rain on your parade), but I believe that type of piston wrist pin -snap ring or circlip- is an accident waiting to happen as they have been reported to come out from the groove and then score the barrel. There was a thread on this a little while back I believe, and it was suggested that they be discarded and replaced with a different type, even though they are the ones provided with the pistons. Cj
 
cjandme said:
If I might.. ( I'm not trying to rain on your parade), but I believe that type of piston wrist pin -snap ring or circlip- is an accident waiting to happen as they have been reported to come out from the groove and then score the barrel. There was a thread on this a little while back I believe, and it was suggested that they be discarded and replaced with a different type, even though they are the ones provided with the pistons. Cj
Click to expand...

I believe it is the type below (either single or double tang) but I don't think it's the one in TomU's picture?

www.rgmnorton.co.uk

PISTON CIRCLIP ROUND WIRE TYPE, TWINS WITH GPM PISTONS (4)

RGM NORTON 067106 WIRE TYPE CIRCLIPS
www.rgmnorton.co.uk

Edit:

the wrist pin circlip thread

I hate when someone hijacks my thread, so I started a new one about the wristpin circlip question From a physics point of view, I would argue that the weight of the return wire on the ends of the wire circlips can act as a bob-weight to compress the circlip as it changes direction Right...
www.accessnorton.com www.accessnorton.com
 
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TomU said:
Ok, back on track. Next up is attaching the barrels. I thought Jim Comstock's method of placing the pistons in the barrels and then attaching the pistons to the connecting rods with the barrel suspended on sockets over the crankcase was the way to go versus the more traditional method of attaching the pistons to the rods and then trying to get the rings from both pistons into the cylinder bores. T
Click to expand...

Its even easier if the engine is stood on its nose and barrel/cylinder with pistons installed on the bench horizontal but same deal rotating the crank so the rods engage the pin bores.
Sockets or spacers was to fiddly for me.
#
The worse circlips were the diameter undersized flat type and one of the reasons I removed the engine again to replace them. (Getting the size recommended by JC )

I am surprised a little that JS does not use KRAMM-Lox wire circlips but those ones will stay in place no doubt.

The wire clips with wings (L.A.B link) are the stock fitment on many Gilardoni pistons and even asked if there had been a failure on one forum (bikes with 100 to 200k miles are common and in my own Moto Guzzi so who knows)
 
Time Warp said:
I am surprised a little that JS does not use KRAMM-Lox wire circlips but those ones will stay in place no doubt.
Click to expand...
JS uses JE Pistons clips, similar to KRAMM-Lox, but without the bend at one end

JE Pistons clips:

JEP-Retainer_2000x2000.jpg


KRAMM-Lox clips:

My What Am I Getting Myself Into Combat Build Thread


The KRAMM-Lox would have been better because the bend allows much easier installation (and you get a special tool). The JE Pistons clips were a bitch (but i don't think they are coming out :)).
 
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Next on to the timing chain. I obtained a RGM lightweight cam sprocket.

IMG_0556sm2.jpg


It provides for multiple timing options and is significantly lighter than the stock sprocket (82g vs 108g). Not sure i needed the timing options, but for the weight savings alone, i opted to give it a go. Only problem was when i went to install the chain, it was very tight. I mean there was no give at all. It was so tight, i couldn't get the tensioner installed. Ok, so is it the sprocket of the chain? The chain was sourced new from AN, but i checked it against the original and it seemed like it was the same size. I also laid the RGM sprocket on the original and it too was the same size. Hmmmm???

I then came across this - "a new chain from Andover norton. It is slightly shorter than the nos chain and usually requires pre-grooving the shoe for the side rails to get enough chain slack"

New hydraulic timing chain tensioner.

Ok here's one more concern about the hydrualic tensioner, Would it dump its oil on long Rough hill climbs over 45' angle and what about wheelies held up close to standing on tail? Throw yourself at the ground and miss! It might loose it's oil if you parked the bike upside-down for a few...
www.accessnorton.com www.accessnorton.com

While the chains looked similar, I should have measured the distance between the pins. My guess is the new chain is slightly smaller. Anywho, I took it over to Greg Marsh to see if he had any ideas (it's great living near someone that knows what they are doing). He pulled the sprocket and filed down the key slightly and reinstalled. That seemed to provide enough slack that i got some slack in the chain, 3/16" slack at the loosest position and 1/16" at the tightest, witthout grooving the tensioner. I think i'm good :)

Installed.

IMG_2756sm.jpg


Also much cleaner than when i started

IMG_1568sm.jpg
 
Now on to the heads

Before:

My What Am I Getting Myself Into Combat Build Thread


After (courtesy of Mr. Marsh):

My What Am I Getting Myself Into Combat Build Thread


Threads look pretty good :)


My What Am I Getting Myself Into Combat Build Thread


I never noticed that a PO drilled for exhaust nut wire. I do not plan on reusing

My What Am I Getting Myself Into Combat Build Thread


I used a JS copper gasket. He supplied some thin copper wire to wrap around the pushrod tunnels and oil drain hole. It's kept in place with pliobond glue as well as the head gasket. The wire was a pain, but i got it glued down and then went to install the head. Jim recommended placing the pushrods in the head before installing the head on the barrel. I had trouble getting the rods in with the studs in the barrel so i pulled the rods out and put them in the barrel. The head went on ok after this, but i though to myself "hmmm, wonder if the rods are seated properly on the valve rockers". I could see the inlet rods through the inlet valve cover and one was off. I could not see the exhaust rods. So i pulled out the boroscope (that thing is becoming handy) and i could see that the exhaust rods were off using the boroscope through the exhaust rocker cover. Ok, lift up the head and try to get a screwdriver in there the move the rods into place. Easier said than done. I really didn't have a small screwdriver that was long enough to reach the rods so i had to pull the head up higher to get a longer (and bigger) screwdriver to reach. It seemed that when i got one in place, another fell out of place. I kept re-lifting the head and fiddling with rods a good dozen time before i got all four seated properly.

Now idiot me, i did not review Mick Hemmings video beforehand on this part of the build. He uses rubber bands on the valve rockers to force the pushrod ends down so that when pushrods aren't dangling around when you try to seat them becasue the rubber band exerts enough pressure to keep the rods in place. Without it, they all just dangle around until the head is seated and (for me) it was just guesswork on how to position the rods before the head was lowered. Also, while checking that the rod were seated by looking through the inlet rocker opening, i noticed i could in fact see (and get to) the exhaust rods through the inlet rocker opening. Now that would have made my life a whole lot easier. In pulling the head off a good dozen times, not sure if the copper wire stayed in the same place i put it in. Also not sure how well the pliobond held up. What i do know is i'm not checking it. Lazy? Probably, but after a good hour (or more) trying to get the damn rods seated, i did not feel like pulling everything apart and starting from scratch. I guess time will tell if i made the right decision (and if i am wrong it will be a whole lot worse than a couple of hours to fix)

All bolted up:

My What Am I Getting Myself Into Combat Build Thread
 
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