EJC

Just noticed this issue when I got my block back from the machine shop. Anyone dealt with this before? I bought this block with no cam so I didn't notice the wear until I got it back and part of the machine work was having the bearings set in. The edge of the cam bearing was sticking out and then i noticed the wear. Is there a fix for this, shim for olds???

TripDeuces

Two things I see right off the bat:
1) Having wear there is not uncommon as the twist on the distributor gear is constantly pulling the camshaft to the rear. There are cam thrust washers made and I know of two different types. Some are just a bronze washer that basically saves the block from wear. Of course it's bronze and is designed to sacrifice itself instead of the block or camshaft. The other is a roller bearing set up that uses needle bearings in a fan type cage. It requires the block to be machined to fit.
That front cam bearing is too far out and will rub against the back of the camshaft. That's a recipe for disaster. It needs to be set deeper in its bore.

2) That pipe plug is incorrect. That hole uses a 'straight' cut thread and not a tapered thread like a pipe plug. It has its own special plug and is a different diameter than the passenger side so there is no way to switch the two and keeps the oil squirt hole on the passenger side. More than likely your machine shop lost it and put that incorrect pipe plug in. They also socked it down so much it probably ruined the threads. The other problem is it may be blocking the oil feed hole from the mains. You can clearly see the passage formed in the block coming up from the main journal. The original plug had shallow threads on it for a reason: It won't block off that passage and allows oil to flow to the lifter galley. Who knows how far that pipe plug extends into that hole? That needs to be fixed.

TripDeuces

Here's a pic of the thrust bearing. The picture also clearly shows the different size holes for the two plugs.

EJC

I just pulled that plug out to see what the threads looked like and I think I got lucky. The plug was a lot shallower than the factory one. I have a couple factory plugs from another block i have and switched it over. Have you used both and what one do you think works better. Would the shim have to be machined into the block as well? Thanks for help by the way.

TripDeuces

I have used both. The shim needs no machining and just sits behind the thrust face on the cam.
The bearing is in my new block and haven't run that yet.

cutlassefi

EJC

Correct me if I'm wrong. I need to have the bearing tapped in flush to the worn out level and add a shim that is flush with the original thrust level? Or machine in a thurst bearing which I would have to find someone to do.

EJC

Or with the crank shim will the cam shim ride over the worn area and dont tap in the bearing any more?

BillK

EJ,

I dont do a lot of Olds engines but having wear in that spot is very common on Big Block Chevys and either a shim or a bearing can solve the problem BUT .... I dont see how anyone can say that you dont need to do some type of machining to make it work correctly. The camshaft sprocket needs to end up in the same position that is was from the factory or you will have a misaligned chain. On the Chevy engines we cut the front of the block so that once the shim is installed the cam sprocket will end up in the correct position. I simply cannot see any other correct way to do this.

Also, I hate to say this but I would really have to wonder about a machine shop that did not see this and tell you about it before installing the cam bearings, if not even earlier in the job.

EJC

I picked the wrong shop foe sure. Block was dropped of 8
Weeks ago. Asked to have it inspected and give me an idea of what it needs.Lesson learned.

cutlassefi

BillK

Yes but I dont know if I would ever put a shim behind the crank pulley also. Now you are messing with belt alignment

Either way, his is not correct and needs to be fixed.

rad

if you use the non-roller thrust washer im sure it won't be enough of an offset to affect the belts too much, id be more concerned with the lack of attention on the front bearing and the galley plugs the the other cam bearings might not be seated right as far as the oil holes lining up or something stupid like that.

EJC

I think I want to go the thrust bearing route that was pictured. TripDueces can you point me in the right direction in a part# or who sells that. I cant find one yet? Thanks,

Eric

TripDeuces

http://www.oldsperformanceproducts.c...d%20Components

http://www.btrperformance.com/products.html

OPP sells it and their thrust bushing/bolt is a quality piece also. I got mine from BTR but didn't see it listed on their site. The bolt might be overkill for a regular flat tappet hydraulic cam but I just threw it out there.
Smitty, OPP, BTR, J&S (closed now), Cutlassefi and maybe a couple others are quality suppliers and good people. Mondello (Lynn not Bernard) and Dick Miller were complete jerks to me and others so you won't find me touting them anytime soon.

EJC

See it now on OPP. Encased Torington Roller. Greatly appreciate your help. I would get from Cutlassefi for sure he was nice enough to walk me through a few things in the past.

EJC

Hi everyone. Have a question or two. TripDueces,did you have your bearing machined in or just put in flush and grind down the cam for clearance. Also, the cam bearing that is sticking out a bit really seems to be fully seated but doesn't look seated because of the previous cam thrust wear. What should I do with that? Or should I not worry about that because the new bearing will be seated over it? Just asking because I think yours might have been done differently than the instructions sent with my bearing.

TripDeuces

My block was machined so that the bearing sits flush with the original surface

EJC

So I have sent my block to the machine shop to have the Torrington bearing machined into the block which they did. The issue I am having now is the allignment of the timing chain. The gear set being used is part#3113 comp double roller. I wound up buying the comp kit with cam OL XE268H lifters, springs etc. With the Torrington in place the cam sits out to far forcing the crank gear from the back of the crank, floating so to speak. When taking the Torrington out and reinstalling the cam the timing chain fits perfect but the cam journals are not aligned up and are visibly off. This Olds project has taught me how to be more patient person. Any advise would be great.

BillK

Take it back and have them do it right ???? The front of the bearing should be flush with the front of the block when it is installed. Did they have the bearing when the did it ? Not sure how they could do it without having the bearing there.



It either that or machine the back of the cam gear to make it work but that is really not the correct way to do it.

EJC

I did give them the bearing. And with the bearing out the chain is alligned but cam is way off, journal and lobe wise. It looks like they milled a portion of the cam bearing as well because it is flush with the newly milled portion for the bearing. I left the block at the shop and he is saying the cam isn't cut right and I just don't think thats correct.

BillK

I doubt that it is the cam. Just sounds like something is not machined correctly. Is the front of the torrington bearing flush with the front of the block ? Any pictures of it with the bearing installed ? Something just doesn't sound right and its very hard to tell without being there to look at it.



Do you or the machine shop have an old cam to compare to the new one ? I know I have a stack of them on the shelf that I use for checking cam bearing fit etc.

EJC

I asked him and he didn't have an extra Olds cam nor do I. I am going back up there to take a bunch of pictures tomorrow and I will upload them for further review. So stumped right now, I will take a pic of the bearing,milled area, cam in with Torrington and show lobe and journal fitment with cam all the way in. Thanks for taking the time.

BillK

If it will help I can take a picture of a cam with a tape measure next to it so you can see the dimensions and where the lobes are. But I really doubt the cam is the issue. I might go by the shop tomorrow if i do I will try to remember to get a pic, if not Monday for sure.

EJC

Thank you sir.

EJC

Thank you sir.

BillK

ej,
This should give you a pretty good idea on the measurement to the center of the front cam bearing journal. If you need more let me know.

EJC

Thank you, I relayed that to the shop. If that measures up then I will send some pics of the overall fitment.

EJC

Thanks Bill the cam measures out from the dimensions you provided. Now, im not sure whats going on?? Machinest said the crank would have to be shimmed in order to align the gears but I don't think thats right.

BillK

I agree. Thats screws up all your pulley spacing etc. I suggest you get a second opinion.



I have a 455 block I am doing for a customer. I just now took a quick measurement from the front face of the block to the surface where the camshaft hits the front of the block. It is 2.008" The block I have has virtually no wear. That should be the measurement to the front of the torrington bearing when you sit it in the block. The picture I attached shows where the measurement is I took.

OLDSter Ralph

I have been following this thread for a while. From what I was understanding from the posts, it sounded like the area for the bearing was not machined deep enough. Shimming the crank doesn't sound like a good idea to me.
The machinist should be giving you answers, NOT you giving him the answers. It sounds to me like you should at least get a "second opinion" as BillK suggested. Personally, I would be loading up parts and finding someone else.

EJC

So, just got word back that from the measurment of 2.008 mine is way shallow. Thanks for that, I will keep you posted.

EJC

It sits at 1.90 and i'm being told they can't go any deeper than where it is��

BillK

Why not ? Do you know how thick the Torrington bearing is ?

BillK

I just took a better look at the picture of the bearing in its package. It looks like it says to machine .135 off the back of the camshaft flange ?? If so, that is where the problem is. Do you have the instructions for the bearing ? If yours is now at 1.900 then it looks like they will have to cut about .108" of the cam thrust surface to get you at the same dimension as the block I have. I can stick a cam in this block and measure down to the front of the cam if they want that dimension.



Sorry I din't look at that picture earlier. Did they have the instructions with the bearing ??

EJC

Instructions on the Torrington was to ground block flush and remove .135 from flange of cam. I would assume thats the thickness or close to it?

BillK

Sounds that way but . . . if they have machined a lot more off the front of the block you cant really go with that. They are going to have to cut the camshaft flange the appropriate amount to get the cam to sit where it needs to be.



I will measure the one I have in a little while when I get finished with a block I am honing.

EJC

When they put the cam in without the bearing the rhe crank gear is seated proper and the alignment of the timing set is good but the cam to cam journals are not alligned. I may get a different block at this point. IDK??

BillK

Not sure exactly what you mean by this ?????



How about a few pictures ? I think you need to get your block back and get it to someone else to look at.

EJC

I'm going to snag it tomorrow get it home on a stand and I will shoot a few pics.