The Stovebolt Site Forums The Shop Area Engine Shop CAMSHAFT AGAIN !!!!!

Got new timing gear and plate installed on cam for my 235 put new cam bearings in but can't get the cam in it looks like it is bent off by about 1/64 of an inch. 3 questions can a cam be straightened? can I use a cam from one of the 216's for the journals are the same? can I take a newer 235 cam and have the journals turned down to fit my block?

Who installed the cam bearings? It's not uncommon to get a cam bearing installed a little crooked and be unable to get the cam back in the block. I have a cam bearing driver that uses the full length of the block to assure the bearings go in straight, but I trashed several bearing sets before I bit the bullet and got the right tool. Don't assume the cam is bent unless you set it up between centers in a lathe and confirm the runout with a dial indicator.
Jerry

I installed the bearings myself bought a Lisle cam installation tool the way they work it would be pretty hard to get a bearing in crooked. plus it is on the 3rd journal that seems to be tight and when you look in the last journal there is a gape at the bottom looks like the top of the journal is about even with the outside of the bearing.

Crankshafts can be straightened, I suppose a cam could be to. A press and two arbors would work, just go slow and steady, checking often. It's junk now, so you really have nothing to loose.

I have checked cams by clamping pointed rods to 2x4's which are then clamped to a work bench. The rods go in the machined centers of the camshaft. Then using a cheap-o dial indicator, I could rotate the camshaft and tell if it was out of round or check lobe lifts. As long as you are not checking one lobe to the other, a flat true surface is not needed. All you are looking for is out of round, even a pin held tight on a fixed object would show out of round.

If thats to tough, find a large flat piece of glass and roll it across, that will tell you the same thing.

Joe

are you sure the bearings and the cam are the same size? Had to get my cam ground down .010 once.

Tried the bearings on the cam before I installed them.

Did you distort the cam when you pressed the cam gear on? I have seen once before a cam bent from an over zealous guy on the press.

there could be several scenarios, once installed there is the possibility the bearings are too small, press fits commonly reduce the inner dimension of a thin item such as cam bearings. Are you sure you have a 235 cam? I had delta cam do some work on my cam, and they somehow lost MY cam, and sent me a GMC cam, which didn't fit, but it doesn't really sound like your problem. Whatever the case, if it is a GMC cam it will have GMC cast into it. Yes you can get the journals ground, just make sure the lobes all fit through the holes, (this is why I had sent my cam to delta in the first place, to have it reground to fit through all the holes). If you have pre-54 235, (small journal) the cams for a 216 and 235 will fit, I think they are actually the same grind. Or it might just be bent, and you can straighten the cam, I believe the manual actually gives instructions on how to accomplish this.

Brokenhead I used a digital calipers to check the journals and they were all what they were supposed to be. I think I'll try to pull a cam out of a 216 just to see if it will fit both of the 216's run so the cam should be half way decent. If that works then I'll take the cam to the machine shop to have it checked to see if it is bent.The journal that it seemed to stick on was a very tight fit so if it does shrink up when installed then that could be the problem I'll have to see if I can find a inside mic to check it. Could you use a hone to remove a few .000's from the bearing?

You usually have to scrape the bearings to remove tight-spot distortions after install. Guys who rebuild these on a regular basis will modify an old cam to have a "cutters" carved into the cam journals, so as you install and rotate it, it will cut the proper bearing clearance. Careful work with a razor blade will shave down the high spots in the bearings that will show up shiny after a tight cam install. Scuff lightly with green Scotchbrite pad after shaving so you can see the next round of adjustments that will be necessary.

A 216 cam will fit in a small journal 235 but the connecting rods will hit it. 235 cams are either notched or turned down between the lobes(depending on the cam) to clear the rods.

Dave can I take the 235 cam that I have and have the journals turned down so they fit in the 235 block that I have? I think the cam I am trying to install is for a 216 because it has a heavier body between lobes than the other cam that I have.

I would need to study both cams but I feel quite sure it could be done.
On the other hand, Grinding notches in a 216 cam to clear the rods may be a lot easier.

Those early cams are forged steel and I would think could be straightened.

Forged shafts can be straightened in a press- - - -don't try it with a cast iron shaft, as it will be straight, but cracked when you're done. On a cast shaft, either crank or cam, find the area of max bend and get it pointing straight up with the shaft supported at the ends on wooden V blocks and smack it with a piece of 4X4 hardwood or maybe a Louisville Slugger. Good luck!
Jerry

First I going to see if I can get the cam in a lathe and see if it is bent then decide what to do in fact I will check both cams. What years were cast? I think this weekend I am going to forget about the cam and work on frame. Maybe put the 216 back in the truck!!!!!

Some 1954's had steel and some had cast. After that they are all cast.