A few engine questions...

[true_w]

First of all, this is my first time tearing into a motorcycle engine, so I'm here to learn. Obviously my experience is lacking. I have a 72 CB350 with about 10,000 miles on it. I believe the top end has been done before based on scrape marks I found under the gasket material. The bottom end still had asbestos gaskets on that I believe are factory installed. One of my spark plug threads was semi stripped, which is one of the reasons I took the top end down. I found this small very thin piece of metal during disassembly. I don't believe it's off any of the piston rings. They seemed intact when I removed them. Any guesses as to what it's from? I thought maybe off the camshaft shims, but they look OK too.

A question about the cam box. There are some what I'd call imperfections in the mold or possibly stress fractures, but they don't seem to run that deep. Anything I should be worried about?

I want to split the crankcase and I was going to remove the rotor, but she won't come off with the rotor puller tool. I tighten it down and I can't get it to come off. Impact driver? Any tips?

 

[LongDistanceRider]

I don't recognize either of the 2 extra metal pieces so no help there.
The cracking in the aluminum is just casting flaws, zero concerns there.
Stick a penny in the drive to clutch basket gears to lock the crankshaft while continuing to tighten the rotor removal bolt. Do Not hit the rotor with a hammer! It will cause the rotor to lose magnetism.​

 

[true_w]

The one piece is not metallic (bronze looking piece) and I believe it's part of whatever bonding material was used to seal the crankcase. I should have stated that the thin metal piece was found after I removed the oil drain plug and oil and reached up in there with my finger. So it came out of the lower crankcase. Another reason why I thought it was a good idea to split the case.

Good to know on the cam box. Thanks.

I've tightened the rotor removal tool all the way down and I can't get the rotor off. I had no intentions of hitting the rotor with a hammer. I was wondering about using an impact driver on the rotor removal bolt tool or is that overkill?

 

[ancientdad]

If you tap moderately on the "puller" bolt, then tighten it a bit more and tap a little more and repeat, it will pop loose from the taper. Just don't be too aggressive with the hammer on the puller bolt

 

[MrPepper]

For the rotor, I have a flat piece of aluminum with holes drilled to match the rotor) and use that to hold it. Some rotors don't have those holes so I jam the penny as longdistancerider mentions. You could maybe try wood but it might split.
How many lbs pressure you putting on the bolt to remove it?


Those stray pieces in the image.
Thin metal def looks like a cam shim.
Bronze stuff is case sealer.

 

[true_w]

I can keep the rotor from moving with the rubber strap wrench seen in the photo. The problem continues to be that no matter how tight I ratchet in the rotor puller tool it won't pop off. The Chilton manual I had recommended threading in the rear axle and putting a rod through the hole and tapping the rod with a hammer. I tried that this morning, but it didn't work. Maybe I need a better t handle rotor puller tool, instead of this one I've been using from CMC?

I'll check the cam shims again.

 

[ancientdad]

The one you're using is the same as the one I have, except mine is a double-ended bolt with the hex in the middle of 2 different size threaded ends for different rotors. I used it on my 450 and had no problem getting the rotor off. If you have a cordless impact or air impact, you can gently tighten the bolt with that and it will provide enough "hammering" action to pop it off. If you don't have any form of impact wrench, you simply tighten the bolt and tap on the end of it with a hammer moderately, then tighten the bolt a little more and repeat. It will eventually get the rotor to pop loose from the taper. You just don't want to beat the hell out of the bolt so you don't affect the magnetism in the rotor

 

[film495]

I don't know if it is recommended, but I've had good luck pulling small flywheels and such - by getting the puller bolt pretty tight, then whapping firmly around the wheel - rotor in this case, with a rubber mallet, not hard - but enough to put a little quick jolt of nrg into the mechanism and if the puller bolt is tight enough, the flywheel or whatever lets go and pops off. if it is stubborn, tighten it to a torque spec that is very firm, but not too crazy, and just tighten and loosen it several times, inside where it doesn't want to let go, this has the same affect as working a stuck bolt back and forth and it loosens the bond you're trying to free up without breaking anything. One time I had a really stubborn flywheel that just would not let go. I heated it up several times with a torch, whacked it, you name it, penetrating oil, just kept going at it and it would not let go. Eventually it popped off with me - at 280 lbs, lifting all my weight on it on a breaker wrench and bouncing up and down on it for about 10 minutes, and it cracked free. Someone had put lock tight on the mating surfaces.

 

[LongDistanceRider]

I don't know if it is recommended, but I've had good luck pulling small flywheels and such - by getting the puller bolt pretty tight, then whapping firmly around the wheel - rotor in this case, with a rubber mallet, not hard - but enough to put a little quick jolt of nrg into the mechanism and if the puller bolt is tight enough, the flywheel or whatever lets go and pops off. if it is stubborn, tighten it to a torque spec that is very firm, but not too crazy, and just tighten and loosen it several times, inside where it doesn't want to let go, this has the same affect as working a stuck bolt back and forth and it loosens the bond you're trying to free up without breaking anything. One time I had a really stubborn flywheel that just would not let go. I heated it up several times with a torch, whacked it, you name it, penetrating oil, just kept going at it and it would not let go. Eventually it popped off with me - at 280 lbs, lifting all my weight on it on a breaker wrench and bouncing up and down on it for about 10 minutes, and it cracked free. Someone had put lock tight on the mating surfaces.

Hitting the rotor is a sure fire way to cause it to lose magnetism, fastest way is to drop it. Even a rubber hammer can cause it because you're disturbing the the magnetic fields with each blow.

 

[LongDistanceRider]

When I removed the rotor from the last engine I had to tie the engine down to limit movement and then with a 1/2" drive 20" length torque wrench set to 200 ft. lbs. it clicked, meaning I hit 200, and then came loose. I've long suspected that Honda has some sort of glue used during assembly but I've never found any trace of it, 1st time off is always a booger.

 

[MrPepper]

OP, can you get a helper to hold the rotor while you bounce around on the bar?
I realize this is a little trickier since you're doing it out of the frame

 

[true_w]

MrPepper --- I believe you are correct in that it was a cam shim. I only found one.

Ancientdad ---I tried my cordless impact driver on the lowest setting and it didn't work.

LDR --- I can get somebody to assist me and try that method. I have a breaker bar and multiple torque wrenches. Not sure if I have one that goes up to 200 ft/lbs, but I'll check.

Looking at my cam shaft here and the lobes. I see some pitting. I assume I need to send this out for service? If so, any recommendations?

 

[MrPepper]

How do the followers (rocker arms) that went to the pitted lobe look? Their pad thickness and wear about the same as others? If so then I would run the cam as is.

 

[true_w]

The long torque wrench did the trick. It didn't come without a price though, the the fly wheel separated from the rotor at the exact moment it popped. A few of the internals popped out. So I'll be looking into how to put that back together correctly. Thanks to everyone for their help this weekend. It's much appreciated.

I'll take some pictures of the rocker arms this week.

 

[ancientdad]

What you described as a flywheel is really just the starter clutch, so not likely any damage was done. Here's the visual. #2 in the first fiche goes into #1 on the back of the alternator rotor in the second fiche, along with the assorted parts shown (caps, springs and rollers).

 

[LongDistanceRider]

Torque wrench was the longest thing I had to use, my sons borrowed the monster breaker bar years ago and still haven't returned it. I was about to buy another one and a 3' section of pipe if it didn't come loose.

 

[Ribrickulous]

AFAIK the two options out there are Delta and Web Cam.

Delta is affordable, but I’ve had communication issues with them, Web is astronomically expensive, especially for rocker arm resurfacing ($75 per rocker!!!).

My camshaft and rockers are out with Delta now. I should know if they’re timely by the end of the week.


Ed
1972 Honda CL350

 

[DoctorRuckus]

Sorry to be late but that is 100% your cam shim. Mine was same condition with only 4k miles on the bike so I replaced it when I did the top end.

Delta cam is the best of the best I think. Easy to send and get back. Just call them a few days after they arrived to make sure you pay so they start on them. Came back like new along with perfect rocker arms surfaces. Just checked my receipt from them. It was $95.40 which included return shipping. 253-383-4152 is their local number

 

[DoctorRuckus]

AFAIK the two options out there are Delta and Web Cam.

Delta is affordable, but I’ve had communication issues with them, Web is astronomically expensive, especially for rocker arm resurfacing ($75 per rocker!!!).

My camshaft and rockers are out with Delta now. I should know if they’re timely by the end of the week.


Ed
1972 Honda CL350

Delta only charged me $18 for resurfacing all 4 rockers.

 

[Ribrickulous]

Yes, they’re to my knowledge the most affordable option around.

LDR found a place on the left coast - California j think, that will do them for $25 a pop.

If a NOS cam surfaces for Oregon Cam to scan, there will be a third (hopefully in between) option for cam regrinds.


Ed
1972 Honda CL350

 

[LongDistanceRider]

Yes, they’re to my knowledge the most affordable option around.

LDR found a place on the left coast - California j think, that will do them for $25 a pop.

If a NOS cam surfaces for Oregon Cam to scan, there will be a third (hopefully in between) option for cam regrinds.


Ed
1972 Honda CL350

Yes, they're based in Redding CA http://www.rockerarms.com/ and after talking to Gary(owner) it sounds like a viable option for us.

 

[RockReef]

If the goal is just to split cases the rotor does not need to come off.
+1 for Delta as well. They recently did my cam and rockers for less than $100. But seeing other posts from this morning I guess I ought to reserve wholehearted endorsement until I actually put my motor back together. Surface finishes do look nice though.
Anyone know the part number for the cam’s side shims? Destroyed one during disassembly because I didn’t expect there to be any shims (first timer)


Sent from my iPhone using Tapatalk

 

[Ribrickulous]

P/N will be found here:

https://www.cmsnl.com/honda-cl350-scrambler-1972-k4-usa_model549/partslist/E03.html#.X1FDOCRq0lQ

You can also make them ?or order them) from shim stock. Put your top end together (including torquing the side covers with gaskets on) to measure the end play, and order a shin that gets you within spec. I believe it’s .1-.3mm, but check the FSM for sure.

I had thought I bungled up the cam by using regular assembly lube and switching to synthetic too soon. Hearing that another grinder won’t touch their cams is worrying, though.


Ed
1972 Honda CL350

 

[true_w]

My apologies for the slow response. I appreciate all the input everyone is providing.

Mr. Pepper... A picture of each of the rocker arms.

Ancientdad... Thanks for the link. I'll attempt to put that back together this weekend.

Delta sounds like the way to go. That's a fair price.

I measured my one good cam shim and it came out to 0.2mm basically. I did a quick search and can't find a replacement in that size. Only for the 0.1mm shim. I don't know about making my own. I guess I'll have to look into it.

 

[DoctorRuckus]

My apologies for the slow response. I appreciate all the input everyone is providing.

Mr. Pepper... A picture of each of the rocker arms.

Ancientdad... Thanks for the link. I'll attempt to put that back together this weekend.

Delta sounds like the way to go. That's a fair price.

I measured my one good cam shim and it came out to 0.2mm basically. I did a quick search and can't find a replacement in that size. Only for the 0.1mm shim. I don't know about making my own. I guess I'll have to look into it.

You plugged the part number into eBay right? I found one of each a few months ago when I was doing my rebuild and bought both. Can’t find the extra in the move and can’t remember which I used

 

[ancientdad]

My apologies for the slow response. I appreciate all the input everyone is providing.

Mr. Pepper... A picture of each of the rocker arms.


Ancientdad... Thanks for the link. I'll attempt to put that back together this weekend.

Delta sounds like the way to go. That's a fair price.

I measured my one good cam shim and it came out to 0.2mm basically. I did a quick search and can't find a replacement in that size. Only for the 0.1mm shim. I don't know about making my own. I guess I'll have to look into it.

Honestly, in the pictures you posted only one of them looks to have pits in it (though the pics don't display the face of them as well as I'd like to see in a couple). In a case like that I'd leave the others as is and get the cam cleaned up, then either look for a good used rocker or just have Delta do the pitted one.

 

[true_w]

Pitting on the left intake and just a hint on the right exhaust rocker. I'll post some better pictures tomorrow.

I did and only found the 0.1mm shim. I'll keep looking. I assume I'll need an 0.2mm to go with my good 0.2mm shim. (I found the correct shims).

 

[LongDistanceRider]

Look carefully at the unpitted rockers. The cam pad should have a nice even arc, typically the center of the pad flat spots to a degree and that would require a resurface as well as the pitted ones.

 

[LongDistanceRider]

Pitting on the left intake and just a hint on the right exhaust rocker. I'll post some better pictures tomorrow.

I did and only found the 0.1mm shim. I'll keep looking. I assume I'll need an 0.2mm to go with my good 0.2mm shim.

There's no rules about stacking shims to get the right clearance so use two .1's to get a .2

 

[true_w]

Thanks, LDR. I'll check tomorrow and provide better pictures.

 

[true_w]

There are some flat spots. The question now is should I trust Delta to do the work? I see in another thread that not everyone is thrilled with the work done.

 

[ancientdad]

Much better pictures, and all of them shown need work. It's a toss-up on Delta right now AFAIK based on some good and some below-average experiences. I had them do some stuff for me a couple years ago and timely communication was their biggest issue then, but some more recently have had less than stellar results with the work done. One thing for sure is their pricing is as good as it gets for the type of work done, given that you get a quality effort.

 

[MrPepper]

Sorry, didn't see this update.
I'd be more curious about a profile pic of the rockers, to see the pad thickness and contour.
Particularly the rocker that mates with the pitted cam lobe.
If you do end up replacing, I would buy a good one off eBay.
Personally I would use your cam (and maybe rockers) as is.
I don't know what your plans are for the bike, but with 10k done I'm sure you can get 30k with the current cam and rockers as long as oil is kept tip top and not allowed to dilute or starve the top end

 

[66Sprint]

Don't use this one (even temporarily)....
It shows deep concave wear and overheating discoloration indicating the eccentric was probably set with the secondary index in the wrong location.....
The matching lobe is likely burnt as well......

 

[true_w]

66Sprint... Can it be reground by Delta or another company? I've made up my mind that I'm going to have the cam shaft and rockers worked on. I hope I'm not misunderstanding you that they need to be replaced entirely?

I can't speak to what the previous owner did or didn't do correctly. I have found other issues when disassembling the bike though.

 

[66Sprint]

I am neither a machinist nor a metallurgist so I probably can't adequately answer that question.....
I do know that when you see a spall (holed defect) showing the original brownish coloration that it is due to an imperfection in the original forging, aggravated by excessive heat and/or pressure that has caused the internal fracture imperfection to expand, resulting in the loss of a "chunk" of the hardened surface material....
Presumably, this could be repaired by adding a "hardface" (high carbon steel?) weld, re-contouring and then heat-treating the part to correctly re-harden it.....
Again, I can't say for sure because I'm not qualified in that arena.....

Best to leave that determination to the people with experience in that process......

 

[DoctorRuckus]

66Sprint... Can it be reground by Delta or another company? I've made up my mind that I'm going to have the cam shaft and rockers worked on. I hope I'm not misunderstanding you that they need to be replaced entirely?

I can't speak to what the previous owner did or didn't do correctly. I have found other issues when disassembling the bike though.

Delta cam will tell you if you can reuse them or not. They don't look worse than mine when I sent them off and they came back new. They'll most likely put a new surface on them and then grind it down

 

[true_w]

Good to know. Thanks for the information!

 

[true_w]

It's been a while since I updated this thread. Still making progress on the motorcycle, but it's slowly.

AncientDad.. I found a broken cap when inspecting the starter clutch and a scored knock pin. I replaced all the springs, caps, and rollers with a new set.

I split the case. Went fairly smoothly and my initial reaction is to be encouraged, but I have to take measurements. I don't see any excessive wear. It does look like the factory used a ton of sealant and it spread to some areas maybe it shouldn't have.

If you go back to my first photo in this thread I had a pic of this bronze looking stuff I found after removing the oil drain plug. It's obviously sealant.

I assume the oil splash guard doesn't come out (rivets? beside the two JIS screws), so just degrease and hit it with a pressure washer to get underneath that plate?

The shifter forks look pretty good to me. They are not burnt or bent and I only see a slight bit of wear on the left and right one.

Is it safe to reuse the shift fork clips or should these be replaced after pulling them?

The transmission looks pretty good to me as well. No broken teeth or obvious wear on the dogs that I can see. Should I disassemble completely and wash in the parts washer or replace thrust washers or anything like that?

I need to take measurements as the manual describes in inspecting the crankshaft, but I don't see anything that looks obviously worn or incorrect.

Any recommendations are appreciated and Merry Christmas to all.

 

[ancientdad]

Honda did slather on the sealant a little heavy on some engines, clearly nothing to worry about as I've seen plenty look like yours. Highly unlikely you'd ever see any broken teeth on gears in Honda constant-mesh transmissions, but you should inspect the openings in the gears where the dogs engage on those that don't have dogs on both engaging gears. The holes in the gear can have rounded edges from the dogs wearing the holes during engagement. As to the windage tray under the crankshaft, I prefer to try to clean under it with, as you mentioned, pressure washing or if available, a speed shop's hot tank which is what I did with mine. I like to leave it alone rather than drill off the riveted heads of the aluminum posts and then drill and tap them afterward. I'd rinse and inspect the gears and shafts, as well as spin-check the bearings for rough spots during rotation. Though they run in oil they can develop little rough spots on the balls in the larger ball bearings on the load ends of the shafts, and give a good rinse to the needle bearings and caps on the small ends. Also, it's very important to be sure the locating pins on the small end bearing caps on the trans shafts are properly located in the bearing cap itself before clamping down the lower case during reassembly or the pins will get pushed through the upper case aluminum and you'll have a repair to do later, as well as erratic shifting. This shows the pins I'm talking about (along with the set rings for the ball bearings) and the second pic is what can happen when the pins aren't located correctly in the bearing caps, note how far out the cap is protruding and the aluminum popped off the top of the pin



Also, one shift fork does have a small mark on it from a gear rubbing, but it's pretty minor. Just look closely at the gears associated with that fork to be sure the dogs are in good condition

 

[LongDistanceRider]

Yeah, looks like they got real sloppy with the case sealer on yours, mine wasn't quite that bad.
The windage tray can be removed, those "rivets" were actually aluminum bosses on the casting that get smashed down to hold the tray. You grind those off and remove the screws. That way the under side can be cleaned, there's lots of caked on garbage under there. Drill each of the 3 stands and tap them for bolts, 6mm.
Take a look at the small square passage at the oil pickup screen where oil actually flows to the pickup. Mine was partially blocked with casting flash that needed to be removed.

 

[true_w]

Thanks for the heads up on the set rings and dowel pins being installed correctly. We'll do.

LDR... I'll check that area closely. The square screen under the oil pump was actually pretty clean of debris when I removed it, but I'll check that passage.

I don't own a parts washer (maybe I should buy one), but I do have an ultrasonic cleaner. I assume that would be fine for gears, but obviously not for bearings. Would dunking the ball bearings and needle bearings in part washer fluid suffice or do I need to have some psi? I've read in one of the manuals not to use compressed air on the bearings, so as not to gall them. After the parts washer flush, just dunk in some fresh oil (bearings) or should I coat it with assembly lube instead? Or both?

Thanks for the help guys.

 

[ancientdad]

Harbor Freight sells an inexpensive parts washer, I bought one about 4 years ago and it's invaluable. They will tell you that you can't use anything but water-based solvents in it, but it's not true. I tried water-based stuff and you may as well wipe the parts off with a rag, that's how poorly it works. I went to Advance Auto Parts and bought a 5 gallon pail of their parts washing solvent, then a couple years later bought another 5 gallon pail of similar stuff from Tractor Supply and the parts washer is doing just fine. That's the right way to do it and including solvent you can probably get into the whole setup for under $100

 

[mike in idaho]

Never tried water-based cleaning solvents, I hate seeing rust on freshly cleaned parts. I just get five gallons of solvent from the local Standard Oil bulk plant, with a quart of atf dumped in to slow down evaporation and drying of your skin. Kerosene works pretty well too.

 

[true_w]

That's what I'll do. I have a Harbor Freight and Tractor Supply in close proximity to where I live. Thanks for the tip.

 

[true_w]

I've removed all of the head gasket material, but there is what I would refer to as some heat staining from the gasket. Should I leave it alone or should I try to remove the staining with a brass dremel brush? Thanks.

 

[ancientdad]

It reminds me more of light corrosion in the aluminum. If the surface is clean and you can't feel what you're seeing, you should be good.

 

[true_w]

I can't feel anything. Feels smooth. Thx.

 

[LongDistanceRider]

I'll be the first to say that I'm a bit a@#$ retentive about clean gasket surfaces.
Draw a razor blade backwards over all the surfaces, get/use a knife sharpening stone to polish them while cleaning or a 8" long block of wood with sandpaper attached, 400-600 grit. Do Not use any kind of powered brush on a gasket surface.
This will work using oil on the surface, don't use it dry https://www.harborfreight.com/combi...dhShYRf3B0-VxjhEOgHSqSB30nlt1mkYaAu5IEALw_wcB
This is what I consider clean, done with a sharpening stone and oil.

 

[true_w]

That definitely looks much cleaner than mine. Thanks for the tip.