Due to the fact that the biblical rains continued here today, I got rained out of a gig at the drags. Which sucks because well, I coulda used the dough. Anyway, that gave me some time to screw with the decrepit, crusty excuse for a motor in my basement. The crank is out along with a couple pistons and rods....several are still frozen in their respective bores.
On with the photos!
Here we see Tom running in an apparent panic that the house was going to explode...NOOOOOOOOOOOOOOOOOO (heh!)
I bet my pop that my mangled pushrod was the result of a busted timing chain. I thought the motor may have lost time and the valve ran into a piston, bending the pushrod. I lost this one. There's no timing chain! The big gear is nylon.
Here's the crank next to the crank out of my 283 (which is probably pissed that it's gotten no attention in the couple years I have had it. The 283 crank is on the left for reference.
The only damage I could find on the Stude crank was this. Can this be turned out?
Some 283 Chevy Vs 289 Stude rod and piston comparo shots. The 283 stuff is on the left in all these photos.
Here's something that has nothing to do with the Stude. It's a NOS Prestolite box from the 1940's. When I re-did the ignition on the tractor I scored a bunch of NOS stuff from the old parts company I've talked about before. I kept this box because I think it's cool.
It's funny...as I looked through the pics I kept thinking...the Stude motor has a lot bigger internals....then I saw the piston top shot....Doh....Then it all made sense... What is the bore on a 289 Stude?
I just shot some detail photos of that...uploading now. It seem to me that the mystery bolt (and it is a mystery. I let out an audible WTF when I saw that) clamps down on the wrist pin some how.
I think the steering engineers also did the piston and rod assy stuff as well.
Hmm, I was thinking the piston pin has a groove the screw sits in the groove to keep the pin from sliding out, it'll be interesting if you are able to get any of those out with the rust.
The knurling on the piston makes me think this engine has had a "budget" rebuild in it's past - that's an old school rebuilders trick to try to prevent piston slap - and make the piston act "bigger" in it's bore....
As far as that bolt at the piston pin - looking closely at the nut end - it appears as if the stud is not completely round - it's flad on the pin side.... isn't it? That makes me think that the bolt is a type of locking mechanism?
Certainly that crank is a stout piece - those main bearings are WAY bigger than than the chevy.
I hope you can rebuild this thing ... it doesn't look THAT bad considering it's previous life.
As far as the steering.... it aint that bad compared to the '54 belair - and Seth can attest to the fact that --- it works well enough to get around the block at 45mph.
It's got Clevite rod bearings in it too. When I saw that I was thinking that it may have bee rebuilt in the past. Think those were factory spec in the mid 1950's?
Yes - the knurl is a clear indication of a previous rebuild, but not necessarily a "budget" rebuild. When I went to Auto Machine school at Ferris State (as it was called then) this was taught as a perfectly appropriate rebuild technique if the bores were within a certain tolerance of stock. It was thought that the crosshatch would hold oil on the lower part of the bore and slow further wear, and that the smaller crown (for the slightly increased bore) was insignificant. This technique was generally used with a hard hone (as opposed to a glaze breaker), which had the ability to somewhat correct a tapered, out or round, or other imperfect bore. I've done a few myself. The piston was knurled considerably oversized and filed by hand to the specified drag fit. I haven't put in specific tolerances as I don't recall them.
The bolt on the rod small end is to retain the pin. Instead of a press fit into the rod like most modern rods, the pin was installed in the rod and then bolted down. It was considered "better" than a "heat and push", modern style pin because you didn't have to heat the rod, which could effect the heat treatment of the rod (or so it was thought at the time). In some of the older engines, I've seen them as pinch bolts, and some were essentially a bolted-in cross pin - I don't recall which on the Study. Of course, in modern engines the increased mass is known to be more of a detriment than any perceived effect on the heat treat - or we use full floaters.
On the bellcrank steering - As you have likely figured out, the bellcrank is there to change the direction of the steering box - the Pitman arm moves fore and aft instead of side to side. Studebaker, like Rambler/AMC, built many parts of the car out of someone else's parts box, and it was likely cheaper to change the direction the box with linkage than to commission a steering box that went the other way - so they did. As others have noted, this style of steering was not all that unusual at that time.
look at the bearings carefully, there is probably a date code stamped on each one such as 8 65 which would be August 1965.
I love this detective stuff
and it's been a long time since I've seen a knurled piston! but yeah it was what the cheapskates did instead of paying $4 a piece for new ones. Doesn't help the ring land wear, either.
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