16 valve B motor - living the dream

[Luke]

Looks nice. Is the flange that was left behind on the jackshaft (and corresponding larger diameter feature in the bronze bearing) just a surface contact for the plate that locates and secures the jackshaft?

Yep, the groove has to be kept in the jackshaft to secure it axially with the plate. The notch in the bronze bearing is just to clear the small shoulder that remains of the original jackshaft OD.

[Luke]

The next step was to press the bearing into the block. As I mentioned before I sized it to be an interferance fit. I ended up with a smidge more than .003" inches interference, of course its enough to make it very difficult to install, as it physically dosent fit!

I decided to let the laws of thermal expansion assist me here.

I stoked up the nice coal stove that I already had heating the shop, and placed the block on top.






and waited until the whole block got nice and toasty:





Meanwhile, I put the bearing in a cold freezer (around 0 farenheit)




When I pulled block down off the stove and bearing out the freezer to my suprise the bearing dropped right into block about 1/3 of the way. The temperatures started to equalize quick though and it needed to be tapped home of rest of the way.

[Luke]

The installed bearing, you can see the supply hole for the oil:





The reason the bushing needs to be no smaller than 37.00:



Thats the OD of the distributor drive gear which needs to pass through the bearing!


This was a little bit of a moment of truth... If I had made any mistakes in the bushing or the block boring the two journal would no longer be in line and with the tight tolerances there was a chance the jackshaft would not install. Luckily it slid right in perfectly, just a smidge of clearance for oil film and it rotates nicely.


edit - added picture of jackshaft installed

[Krister K]

Nice work!

[GOLFGURU]

WOW Luke, you are a true Saab guru..That engine looks like its gonna put out some serious tork..A work of mechanical art...WOW!

[SwedeSport]

Great Job Luke, wish I was making ANY progress on my projects. You should come to my shop for a weekend so I can say that something got done in my shop this winter!

[DrewP]

I wasn't even thinking about it till you posted up about pressing in your bushing, but did the ID get enough smaller to mess with your planned clearance? I see the drive gear still slides in, but did you measure the bearing ID after install against what it was when you cut it?

With such a thin wall to take the interference I'm not sure I would have remembered that ahead of time too since you'd have to cut it oversize ahead of time and have it compress back down to desired dimension?

Lookin' good man, I still don't even have a roller, and now trying to come up with some projects for my customers and the net to get a little spending money flowing to pay for brakes and things like that.

Drew

[Luke]

I wasn't even thinking about it till you posted up about pressing in your bushing, but did the ID get enough smaller to mess with your planned clearance? I see the drive gear still slides in, but did you measure the bearing ID after install against what it was when you cut it?
With such a thin wall to take the interference I'm not sure I would have remembered that ahead of time too since you'd have to cut it oversize ahead of time and have it compress back down to desired dimension?
Drew

I did take the close-in into consideration - theres actually a formula for calculating it on oillites website. I erred on the slightly small side and had a design in my head for an adjustable reamer on a long piloted shaft just in case, and a very fine grit ball hone at the ready. The close-in ended up being perfect without any reaming which was a nice bonus.

[DrewP]

How much did it close up? (You are awesome).

[Jordan]

While I was digging through my stuff I found an 8-cog oil pump shaft I set aside for you. I think I might actually have two.

[Luke]

How much did it close up? (You are awesome).

It closed up about ~ .0015" on the ID, with a .0035" press fit on the OD.

[Luke]

I have for you all on this fine winter day some rather momentous pictures.

The bulk of the machining on the cylinder head itself is completed!

On the cylinder head base, the combustion cambers are cut, the guides in and seats have a valve job.







Some detail shots:

[spgeebee88]

wow! congrats!

[Luke]

Again I would like to thank Ron at M2race for pulling this off. Him and I have been working on this for many months and without his expertise this never could have been accomplished. A stellar job to say the least. The saab prints left a lot up to interpretation and between his knowledge and mine we were able to sucessfully fill in all the gaps.

[Luke]

And a little before and after just because: