67 Sunroof Engine Build

[FreeBug]

[67 Sunroof]

Double post-sorry

[67 Sunroof]

Ok tonight I went out and double checked the notching of the bearings, set the bearings in place, and marked them in relation to the dowel pins and checked for looseness in the dowel pin holes. All good!
I sat the cam bearings in place and had to notch the case for the double thrust bearings. They fit great.
When do you “set” the cam in place with the bearings? (Tap the cam on both sides to set the thrust?)
After the case is bolted up on mock up or while it’s open? I will also need to put the end bearings on the end of the crank.
Ugh...I have this cb counterweighted 69mm crank here and you guys keep saying 74mm.........

[67 Sunroof]

Ok today I opened the air transfer windows up to reduce turbulence.
The photos I’ve seen of people doing this seem to take the entire ledge down to being flat. It appears there is a “swoop” that directs the air toward the bottom of the pistons. I’ve taken pictures below that helps describe what I am talking about. I’ve left the angled metal in the case for now but will take it down flat if it’s better.

[67rustavenger]

When I set the cam bearing thrust. I laid the cam and closed the case with the cam only in place. Torqued the case as well. I tapped the end of the cam through the cam plug hole rearward. Then tapped the other end of the cam through the oil pump opening. Opened the case up and checked the cam bearing thrust.
Super easy job.
Make sure to lube the bearing surfaces before setting the cam or crankshaft.
Keep your hands clean when working inside the case. It makes a difference.

Good Luck.

[67 Sunroof]

Thanks man! That makes sense. Any thoughts on the “swoop” it almost seems like it’s there for a reason. Does air just transfer between the windows back and forth? If that’s the case (CASE-get it??? ) then I’ll just take it off and make it flat.

[67 Sunroof]

Yesterday I deburred the case, opened the windows up a little more, as well as opened up around the cam journals and top of case for airflow and cleaned the crap out of the case and the oil galleys ready for my first mock-up. Exciting!!!
Set the cam bearings in place and put some assembly lube on them. The cam didn’t exactly “drop” in place. The cam gear end “snapped” into place so I’m thinking it is a bit too snug-or is it because I haven’t “set” the cam yet? (Where people tap both ends to set the double thrust bearing into place)
I tapped both sides but it still feels a bit snug....let me put it this way-it doesn’t turn easily and I’m guessing that isn’t what I want.
Also, I dropped the lifters into place with some assembly lube and most move up and down nicely but 2 are a bit snug as well. Question is: do I sand the lifter bores or the lifters themselves? I would think a lifter could be replaced and the bore cannot.
?

Also, do people deburr the cam? I was thinking a slight bevel on the CORNERS?
I had read that the factory did it on the stock cam and it might be a good idea...
Thoughts?

[Pruneman99]

The CB cam I got was very sharp at the lobes. deburr for sure. I used a Dremel tool with a stone to knock down the edge all the way around.

[67 Sunroof]

Just did. I sat reallllly still on the ground and cradled it like a baby. Haha
Turned out good. Got to go to work.
I used some scotch brite red in the lifter bores and they are great now without any wobbling
So far so good!

[Clatter]

Just because someone else would have built a stroker doesn't mean it's the right thing to do for your first build.

Additionally,
Small strokers like 74 are a waste of time IMHO.
Back in the day, when 'B' pistons were developed,
It was all engineered around an 82 crank and stock length rods.

If you are going to go through the whole deal of buying a stroker crank,
And good rods to match,
and clearance the case,
and doing cylinder trimming or shims,
Plus pushrod trimming, and all of the other stuff that goes along with it,
You're better off going big.

Might as well go 82 if you're building one,
Or,
better yet, go Chevy journals and 84 or 86.
And that leads to all kinds of other things...

Keeping the build simple is priority #1 for your first build.
You want success.

What a 74 crank would get you is a bit more power lower in the rev range,
But if the rest of the build was otherwise the same,
it wouldn't make much more overall power.

I believe in keeping the meat in the crank cheeks,
and long skirts on the pistons for longevity.

What you are building will be mild for driving around town,
and make some beans when you want by spinning it.

So,
don't feel like you're doing anything wrong here.
Small stroker cranks are just the current fad on the Samba.
_________________
Bus Motor Build

What’s That Noise?!?

[Clatter]

Something else -

Try putting one of your cylinders into a hole to check what the bottom of the cylinder looks like in place.

Sometimes you can open up the window only so far before the bottom of the cylinder is blocking the flow anyways..
_________________
Bus Motor Build

What’s That Noise?!?

[67 Sunroof]

This isn’t a small stroker. It’s a 69mm crank.
1776 build. I want it cool running and get decent gas mileage with a little more pep.
I think I’m on the right track don’t you? I just figured while I have the case opened up I may as well clean things up while I am in there.
I think the dellorto drla 40’s might be overkill though for such a small motor.

AND...
I already paid for cb to balance the whole assembly...(crank, rods, pistons, flywheel, clutch,etc...
If I went bigger at this point I would have to send it all back to rebalance again.

[67 Sunroof]

[Clatter]

I'd just be looking and thinking about how the air moves under the pistons..

Adjacent pistons on the same side of the motor move opposite of one another.

The volume of oil/air underneath the piston has to either compress, or go somewhere else when the piston goes 'down'.
Because there is an adjacent piston next to the other on the same side going the opposite way.. The windows are there..

Unfortunately,
On the opposite side of the motor, one would hope that there was a piston going the opposite way.
I.E. #1 would see a rising piston at #3 cross the case from it when it was dropping,
But,
Alas,
The opposite side of the motor has a piston dropping as well,
And the windows are the only way to move the air under the pistons as they move..

So,
You basically just make sure that the flow from adjacent cylinders is as free/easy as possible.
You'll want to open up and smooth the windows, and any other places, as much as you can, without weakening the case.

Unlike porting a head, there's not the consideration of velocity at work.
You basically just want to hog it out as big as is practical and polish it up..


I'm glad you went with 1776.
You made a good choice.
Don't let anyone plant a seed of regret..
_________________
Bus Motor Build

What’s That Noise?!?

[67 Sunroof]

Yeah, I’ve been thinking about my choice.
Another well known member pm’ed me and said 1776 is a great choice for what I want.
I have another full motor here to do a wild and crazy build IF I want to in the future.

[67 Sunroof]

Ok, got to get out in the garage for a few hours today. Hot as hell though....
I was unable to get the cam to turn by playing wack-a-mole on the sides of the cam so I had to sand the faces of the bearings down a tad.
I got some wet/dry and a piece of glass and gave each bearing 10 free rides on the bumpy stuff. Cleaned them up and put them back in the case. Torqued the case down and guess what?
It still didn’t turn!
Just kidding.
It turned freely but has like very little endplay? It spins fine though!?
I think too much endplay on a cam will give erratic timing is that correct?
So, getting all excited I put the cam bearings back in the box and decided to check out the oil pump. It’s a cb maxi 5. I wanted to see how well the hole lined up with the hole in the case. I had read where the hole sometimes didn’t line up with the oil pump so I pushed it in.
Uh oh...

BEFORE:

AFTER:

To get it cleaned up I wound up taking my dental pick and running it down inside the hole. I could feel a lip at both ends. I scribed a line and pulled the pump out.
I took my Dremel and a carbide bit and opened it up to match the case. I then opened the case hole up to blend with the pump hole. (I’m deadly with a Dremel I swear!!)
Slid the pump back into the case and it turned out pretty damn good. I then took Clatter’s advice from his thread (scotch brite on a wooden dowel with a slit in it) and cleaned up the pump hole and the case hole.

Since I was on a roll. I put the cam back in with the cam gear and wanted to see if the oil pump bottomed out in the slotted end of the cam. I had read a few things about the cam gear BOLTS hitting the oil pump case sometimes and the drive gear of the oil pump bottoming out in the slotted part of the cam.
Anyway.........
I had no issues with the cam gears hitting-not even close. When do people have issues with them hitting?
And the drive gear sits fine in the cam without bottoming out. Yeahhhhhh!

I put the gears back in the pump and ran the face over more wet/dry and a piece of glass to get it super flat.
I took the pump and cleaned it up really well with hot water and dishwashing detergent. Dried it and put into a ziplock bag.


Ok, I dug the crank out and decided to double check my main bearings.
Ok here is where things start to go weird.
I laid the bearings in their journals and they fit perfectly so I marked the dowel pin hole and the sides with a marker. I checked the dowel pins for looseness and they are good.
I had already notched the bearings for better oil flow and they all looked good.
I decided to test fit the thrust bearing? on the end of the crank and ..........
It doesn’t fit.
In fact I tested all of my bearings and none of them fit.

I chamfered the edges on the cam. Should I do more or is that enough? I also dropped the lifters in their bores and made sure each one fit. Once I had each one moving smooth as butter inscribed the bore and lifter to keep them in order and not mix them up. I also checked the clearance between the cam lobes and lifters. The cam is very mild so didn’t have to worry about clearance issues there.

So that’s where I am. Stupid newbie 1st builder question.
Do people open up the bearing or turn down the crank journals?
Anyway, enough rambling for the night. I’m beat.
Any thoughts or helpful hints would be GREATLY appreciated.
Thanks!

[VW_Jimbo]

What does the bearing box size say?

What size is the crank?

What size is the case bored out to?
_________________
Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!

[67 Sunroof]

The case was bored .020.
111-198-475T is on the box.
M1-4904TP 020 (probably .020)?
I realized I’m gonna have to sand some more off of the cam bearings to allow for expansion. The cam gear is aluminum and the bearings are steel. I believe I need .004-.005 clearance?

Also,
Potential mistake! Putting the cam gear on...dot goes up top and the last lobe must point down. Gotta check on that one. That would suck for sure.
Whew! Got lucky! I’m good.

[67 Sunroof]

Ok, I received the new main bearings and they fit! Yeah!
I also (based on others recommendations) purchased new cam bearings. They haven’t had much luck with the Silverline ones.
I notched the mains last night and installed the Mahle cam bearings. They felt “beefier”. Not sure why.
I DID have to sand the thrust a tiny bit. Cam spins free and I have clearance in the thrust now.
So what’s next? I guess putting the timing gear and bearings on the crank and then putting rods on the crank.
Anyone have a good thread on installing rod bearings?
I have the CB H beam rods with ARP bolts and need to torque them down and check for stretch and whatnot....

[67 Sunroof]

Chugging along with my build! (Thanks to you guys)
Measured the endplay and determined my shim stack. Installed the crank, cam, and sealed the case up with Curil K2, Torqued down the 6 mains to 25ft/lbs and smaller nuts to 15ft/lbs.
This is the stage I am at now:

I torqued the gland nut to 320ft/lbs.
What’s next? Oil pump install, install head studs and fitting cylinders?
And what’s Dirko used for? (I have both)
Any suggestions/help would be greatly appreciated.