Topic: Sandcast Engine #1770 rebuild - it made it!

[HondaMan]

Mark….. amazing story, must have been a fascinating time! I went through all my old head gaskets and found one (made in the USA, “Best Gasket”, no less) that lined up with all the holes perfectly and had really nice crimped copper rings around each bore hole. I think there’s a photo of it in my project thread. It fit so well, I snipped off the tab from the extra hole and used it. Fingers crossed!

Thanks, maybe I'll take that approach? Certainly the holey one that is the K1 type won't be the best at sealing in that spot without some sort of extraordinary 'help'.

[HondaMan]

The Final Drive bearing saddles for both bearings have some unusual punch-mark-like 'nicks' in them. These were done by someone, not Honda. Since the final-drive bearing (outer side) is also the wrong one (no bearing retainer groove in it) I'm wondering if someone wasn't trying to make these marks to hold the wrong bearing in place? Dunno... I smoothed them back out, flattened them by placing a K4 final-drive set (neither bearings have grooves in he K4/5/6 type) in their saddles, and torqued the cases together to see if it will seal. It looks like it will, now.

I'm supposing: since Honda's parts fiche for the [normal] K0 doesn't show the grooved bearings, the wrong bearing got used on this shaft (no groove, nor retainer in the parts for the engine) and probably had a bad habit of climbing out of the cases after it ran a while, pushing out the seal and making a big oily mess? Maybe...

[PeWe]

My K2 cases had punch marks like that too. I bought cases totally empty.

A friend told me that someone must have done that to make the ball bearings to sit tighter.

He had seen that in other engines too. He has restored many engines for other people.

I did not smooth out the surfaces. The cases had been assembled like this earlier.

I can understand if the bearing surface on the primary chain hub had those since that wide bearing sometimes do not sit crimp tight, possible to be lifted by fingers.

[69cb750]

These were done by someone, not Honda. Since the final-drive bearing (outer side) is also the wrong one (no bearing retainer groove in it) I'm wondering if someone wasn't trying to make these marks to hold the wrong bearing in place?

Yes, that was the plan and bad.

I'm supposing: since Honda's parts fiche for the [normal] K0 doesn't show the grooved bearings,

Parts manual shows the groove and retainer, [/quote]
Inner bearing 91002-300-008 retainer 13495-300-000
Outer bearing 91003-259-000 retainer 13491-259-000
"259" is a CB77 superhawk

[MRieck]

My K2 cases had punch marks like that too. I bought cases totally empty.

A friend told me that someone must have done that to make the ball bearings to sit tighter.

He had seen that in other engines too. He has restored many engines for other people.

I did not smooth out the surfaces. The cases had been assembled like this earlier.

I can understand if the bearing surface on the primary chain hub had those since that wide bearing sometimes do not sit crimp tight, possible to be lifted by fingers.

I have seen people use punch marks too....from gasket surfaces to bearing saddles. If you need insurance use some green Loctite.

[PeWe]

My K2 cases had punch marks like that too. I bought cases totally empty.

A friend told me that someone must have done that to make the ball bearings to sit tighter.

He had seen that in other engines too. He has restored many engines for other people.

I did not smooth out the surfaces. The cases had been assembled like this earlier.

I can understand if the bearing surface on the primary chain hub had those since that wide bearing sometimes do not sit crimp tight, possible to be lifted by fingers.

I have seen people use punch marks too....from gasket surfaces to bearing saddles. If you need insurance use some green Loctite.

Loctite on the primary hub ball bearing is something I consider on one additional unit I have.
Loctite 648 low viscosity.
I have also 638 wich is thicker, up to 0.25mm gap, not for a rather tight bearing.

[HondaMan]

When I bolted the cases with the normal K4 final-drive setup I have on hand, it held the bearings tight as a clamp. I might Plastigage them when I get the actual outer bearing, it is enroute.
    I'm supposing: since Honda's parts fiche for the [normal] K0 doesn't show the grooved bearings,

Parts manual shows the groove and retainer,
Inner bearing 91002-300-008 retainer 13495-300-000
Outer bearing 91003-259-000 retainer 13491-259-000
"259" is a CB77 superhawk

Thanks for the tips!
Honda's 'unified' partnumbers (these began in 2002 or so) changed from the old manuals and have had me 'chasing numbers' for almost a month now.
What my trail led to for the K0 "up to 1044805" was their current #91003259000, which has again been subbed to #91004438003, and I ordered: I got an ungrooved bearing.

But...I don't think the K0 manuals include the sandcast, especially since I've seen sandcasts with these retainers in them, and not so, both kinds. 

So, I last ordered (this week) the #91007300008, again now subbed to #9101071003, supposedly to require also the retainer, which [hopefully] means it is grooved: we'll see how it goes?

I have lots of ungrooved final-drive bearings, now, probably a lifetime supply...

[HondaMan]

My K2 cases had punch marks like that too. I bought cases totally empty.

A friend told me that someone must have done that to make the ball bearings to sit tighter.

He had seen that in other engines too. He has restored many engines for other people.

I did not smooth out the surfaces. The cases had been assembled like this earlier.

I can understand if the bearing surface on the primary chain hub had those since that wide bearing sometimes do not sit crimp tight, possible to be lifted by fingers.

I have seen people use punch marks too....from gasket surfaces to bearing saddles. If you need insurance use some green Loctite.

I hope it doesn't come to that!
I remember an uncle of mine (he was a lifelong Ford mechanic, and excellent, highly desired) telling me how they had to do that in flathead Fords during WWII because they couldn't get bearings of the right oversizes then, only standard ones. I worry because he told me "it works, but doesn't last very long".

[newday777]

When I bolted the cases with the normal K4 final-drive setup I have on hand, it held the bearings tight as a clamp. I might Plastigage them when I get the actual outer bearing, it is enroute.
    I'm supposing: since Honda's parts fiche for the [normal] K0 doesn't show the grooved bearings,

Parts manual shows the groove and retainer,
Inner bearing 91002-300-008 retainer 13495-300-000
Outer bearing 91003-259-000 retainer 13491-259-000
"259" is a CB77 superhawk

Thanks for the tips!
Honda's 'unified' partnumbers (these began in 2002 or so) changed from the old manuals and have had me 'chasing numbers' for almost a month now.
What my trail led to for the K0 "up to 1044805" was their current #91003259000, which has again been subbed to #91004438003, and I ordered: I got an ungrooved bearing.

But...I don't think the K0 manuals include the sandcast, especially since I've seen sandcasts with these retainers in them, and not so, both kinds. 

So, I last ordered (this week) the #91007300008, again now subbed to #9101071003, supposedly to require also the retainer, which [hopefully] means it is grooved: we'll see how it goes?

I have lots of ungrooved final-drive bearings, now, probably a lifetime supply...

Mark
Hmmmm.
South Sound shows 91007-300-008 as for K1-K2 not the sandy so it may not have the groove.....

Looking at CMS, they show 91003-259-000 was subbed to 91004-438-003, was subbed to 91003-KY2-003. Is 91003-KY2-003 what you got last that was ungrooved? as it shows the groove in the bearing picture.

[PeWe]

Yamiya has lots of ball bearings too.
I ordered 2 complete sets several years ago when it was much cheaper, shipping too.

https://www.yamiya750.com/index.php?main_page=index&cPath=21_250_53
These bearings with friends for K0?
Item 20 etc? With nick and without.

Or was it different earlier, before K0?

[HondaMan]

When I bolted the cases with the normal K4 final-drive setup I have on hand, it held the bearings tight as a clamp. I might Plastigage them when I get the actual outer bearing, it is enroute.
    I'm supposing: since Honda's parts fiche for the [normal] K0 doesn't show the grooved bearings,

Parts manual shows the groove and retainer,
Inner bearing 91002-300-008 retainer 13495-300-000
Outer bearing 91003-259-000 retainer 13491-259-000
"259" is a CB77 superhawk

Thanks for the tips!
Honda's 'unified' partnumbers (these began in 2002 or so) changed from the old manuals and have had me 'chasing numbers' for almost a month now.
What my trail led to for the K0 "up to 1044805" was their current #91003259000, which has again been subbed to #91004438003, and I ordered: I got an ungrooved bearing.

But...I don't think the K0 manuals include the sandcast, especially since I've seen sandcasts with these retainers in them, and not so, both kinds. 

So, I last ordered (this week) the #91007300008, again now subbed to #9101071003, supposedly to require also the retainer, which [hopefully] means it is grooved: we'll see how it goes?

I have lots of ungrooved final-drive bearings, now, probably a lifetime supply...

Mark
Hmmmm.
South Sound shows 91007-300-008 as for K1-K2 not the sandy so it may not have the groove.....

Looking at CMS, they show 91003-259-000 was subbed to 91004-438-003, was subbed to 91003-KY2-003. Is 91003-KY2-003 what you got last that was ungrooved? as it shows the groove in the bearing picture.

What I got from them in the end is #91001-071-003, ungrooved.

Yeah, I'm not sure what happened between the time I ordered a [picture of a] grooved set and the time it shipped. The number(s) I ordered from CMSNL were the numbers with the correct images, but of that pair I got a grooved inner (smaller) one and an ungrooved (larger) outer one. That one also fits in the tranny, so I have a 'spare' of it, now(?). I ordered the other one last, so maybe it will come grooved. This issue with the grooved and ungrooved final-drive bearings has long been a tangle. I think Honda even got THEMSELVES tangled up in it during the late K2 and the whole K3, because the final-drive output saddle has 2 grooves in it in many of those cases. This was when they were switching from the 1-row output bearing to the dual-row version, and the late K2 and all the K3 came both ways. I have seen K3 bikes with the output shaft seal recessed about 1cm into the cases when the narrower 1-row bearing was installed (at Honda) because the seal has to sit against a flat surface, so they used a full-round retainer (the seal sits against it, as does the bearing face). I've also seen the K7 (early ones) engine this way when a single-row bearing was installed and an additional full-round groove cut for a full-round retainer, also leaving the shaft seal sitting about 0.5 cm into the hole. This area of these engines probably received more mods and attention than any other over the 750's tenure. I still remember reading Honda's [unofficial] 'shop notes' about the new 2-row bearing coming out, and realizing they didn't understand where the failures were coming from - while obviously their Engineering Group couldn't decide on the best way to hold in the final drive shaft! The failures were due to people using the (then new) "Tagalong" motorcycle carrier that mounted to the family station wagon's bumper hitch ball, holding the bike's front tire about 8" off the ground, pulling the bike behind the car. This burned up the 750's final-drive bearing for lack of oil, while almost all other bikes had wet-sump oiling that would just move the oil to that shaft when the bike was raised. This probably prompted the switch to the 630 chain with master link in place in place of the endless style 530 chain, when (somewhere around) 1976 they issued a statement telling Sales to advise the customers to not tow the 750 behind their vehicles unless the drive chain was first removed.

Honda truly paid a price for making both the first mass-production Four and creating a whole market for it out of thin air. Kawi and Suzuki (and later, the straggling Yamaha) all benefited greatly from watching Honda get beat up over these things, yet still the latecomers could not make 100,000 mile I-4 bikes. These are the things legends are built on!

[newday777]

Yamiya has lots of ball bearings too.
I ordered 2 complete sets several years ago when it was much cheaper, shipping too.

https://www.yamiya750.com/index.php?main_page=index&cPath=21_250_53
These bearings with friends for K0?
Item 20 etc? With nick and without.

Or was it different earlier, before K0?

Yes Per, same on sandy and early K0.
#20
Yamiya E102 bearing number. Too bad they don't reference the Honda numbers or that it's the sandy. At least they show the second edition without the retainer groove next, same bearing dimensions.

[HondaMan]

Yamiya has lots of ball bearings too.
I ordered 2 complete sets several years ago when it was much cheaper, shipping too.

https://www.yamiya750.com/index.php?main_page=index&cPath=21_250_53
These bearings with friends for K0?
Item 20 etc? With nick and without.

Or was it different earlier, before K0?

I think there is as much confusion about the groove vs. no-groove bearings in the sandcasts mostly because they came both ways and the parts listings were changed so often that no one knew what was correct. It wasn't until the early 1980s that corrected drawings appeared for the Parts Lists: in all 3 shops were I worked in the 1970s we had to just read the parts lists' typed descriptions (no pictures nor drawings) to find the parts we needed. The standing joke back then was, "This is how Honda stocks up its dealer's Part Departments, by getting the wrong parts all the time." There was quite a bit of truth in this, and guys like JTMarks77 on eBay have gone around and collected all those leftover 750 and 500/550 NOS parts from those dealers where they've been lying around for decades, now our gold mines.

[HondaMan]

Yamiya has lots of ball bearings too.
I ordered 2 complete sets several years ago when it was much cheaper, shipping too.

https://www.yamiya750.com/index.php?main_page=index&cPath=21_250_53
These bearings with friends for K0?
Item 20 etc? With nick and without.

Or was it different earlier, before K0?

Yes Per, same on sandy and early K0.
#20
Yamiya E102 bearing number. Too bad they don't reference the Honda numbers or that it's the sandy. At least they show the second edition without the retainer groove next, same bearing dimensions.

That's an interesting listing that contains another clue: "Manufactured by Honda". Notice the flat-ground face of the grooved bearing: I suspect I may be ordering one of those next if the one enroute from CMSNL isn't the ground face. I really don't want to try to remove 0.5mm of hardened bearing race to get a fully-seated shaft seal fitted! It's probably bearings that Honda had sent out for additional work, which would be the JIS-groove and the flattened race face. The JIS grooves disappeared as an industry standard in 2002 when Japan joined the EU's standards and went DIN on everything instead.

[HondaMan]

Cleaning up the gearbox, found there were 6 water-damaged teeth on the C2 gear(!). In closeup looks it appears that 2 of them could shear off their tips with a good hard shift. Gotta go get one from my collection - starting to run out of these!

[newday777]

So this is the damage area?

[RAFster122s]

I take it that is tiny chunks missing from the face of the gear teeth…

[HondaMan]

So this is the damage area?

Yeah, it's hard to see in the picture, but there are 6 teeth in a row there with the damage on them, and it is deep enough that the tips of at least 2 of them will come off after not-too-far-down-the-road, There is a 'high water mark' across the clutch housing and the back of the primary gear, and this was sitting in that water at some point. The other gears were, too, but they were protected with oil (good oil) and had collected a crust of mud on top of the oil instead of wetting the gears. Had to clean each tooth individually on every countershaft gear, this one was in the deepest part of the water. The engine appears to have been sitting tilted over toward its right side when the water got it in, about 30 degree angle, it seems. Here's some more shots of that high-water mark on other parts.

[HondaMan]

The water got into the clutch hub's cushion and froze up those 2 thin bearings inside, so I had to pull those out and scrap them. They are very rusty!
The clutch hub itself is missing the outer ring that is a separate part in these early ones, which Honda supposed would help lift the top plate (or 2, if so mounted) from the stack when the clutch was pulled, reducing its ON-OFF box feeling a little bit. I found one in Canada, so it's enroute.

[HondaMan]

The next problem I just discovered on Friday is: the oil plug's hole is stripped! There is also a minor crack along the flat bottom of the oil pan that I didn't notice until after the paint. I need to look closely to see if I need to get that welded. too. Might be a good idea. It looks like the engine was dropped (multiple times) on the flat bottom, probably when it was being moved around. The later oil pan's shape (K0 and onward) tends to roll the engine forward and cause a 3-point landing when set down hard (on the oil drain bolt and 2 places toward the front of the more-raised pan). Those don't crack and crater this cover so much.

[grcamna2]

The next problem I just discovered on Friday is: the oil plug's hole is stripped! There is also a minor crack along the flat bottom of the oil pan that I didn't notice until after the paint. I need to look closely to see if I need to get that welded. too. Might be a good idea. It looks like the engine was dropped (multiple times) on the flat bottom, probably when it was being moved around. The later oil pan's shape (K0 and onward) tends to roll the engine forward and cause a 3-point landing when set down hard (on the oil drain bolt and 2 places toward the front of the more-raised pan). Those don't crack and crater this cover so much.

Could the owner of this K0 engine live with a small bead of weld on the bottom of his original K0 oil pan ? ! 

[HondaMan]

The next problem I just discovered on Friday is: the oil plug's hole is stripped! There is also a minor crack along the flat bottom of the oil pan that I didn't notice until after the paint. I need to look closely to see if I need to get that welded. too. Might be a good idea. It looks like the engine was dropped (multiple times) on the flat bottom, probably when it was being moved around. The later oil pan's shape (K0 and onward) tends to roll the engine forward and cause a 3-point landing when set down hard (on the oil drain bolt and 2 places toward the front of the more-raised pan). Those don't crack and crater this cover so much.

Could the owner of this K0 engine live with a small bead of weld on the bottom of his original K0 oil pan ? ! 

It may come to that!
But, I'd finish it smooth anyway, so all that would be there would be a smooth line, under the [re]paint. These oil pans are unobtainium now.

[HondaMan]

The hole for the oil bolt had very buggered-up threads, so I got a new 12x1.5 tap for it yesterday and fixed that.

Then came the chains. The old primary chains are toast (rust, actually) and the cam chain is MIA. I have a set of chains that came from a K4 engine that had 6k miles on it and a hole thru the cases where the final-drive chain obtained unauthorized entry one day, and I've been saving them for just the right place and time: this is it!

So, I installed the crank, rods and chains last night.

I still have to find 2 of the roller bearings inside the clutch. Honda listed them until I actually ordered them, then they sent an e-mail telling me "Nope...", so I'm back to shopping for those two. Honda appears to be ignoring the statement they made almost 2 years ago that they will support these. Maybe it's a good time to start making some of these parts for sale in these forums, from their OEM vendors? Just a thought...or, if I can ever get SOHC4shop.com back 'up' again, maybe I'll start doing that there.

[HondaMan]

Interesting place to get oriental bearings:
https://bearingsdirect.com/

[HondaMan]

Today it got a better C5 gear and C4 gear, both had bad teeth in them.