View Full Version : Cam bearing question and FO8 question

08-17-2009, 08:04 PM
I got my block back the other day from the machine shop and after a close inspection I found two problem areas. Alignment for the oil holes in the Cam bearings, and pitting on one of the faces for the cylinder liners were the FO8s would go. Has any body installed cam bearings and found the holes don't line up very well after you get the retaining bolts in place? 30 60% blockage in some of the holes. And does the first bearing back from the front bearing have one or two oiling holes. Both the 2nd and 4th bearings have two holes in them for oiling, and one for the retaining bolt. I know the forth bearing has an extra hole for the valve train oiling. Did they do this to keep production cost down or did the machine shop block one hole in the block? This was the only work other than machining that the shop was going to do. I'm sure glad they did not put the engine together for me. (KA BLAMO)

Next problem, After close inspection I found that one of the cylinder liner bores has some pitting on the bottom were the FO8 gasket would sit for the liner. Has anybody had to deal with this or is it time to be looking for a new block. Is there a way to turn a few thousands of the ridge and go with a thicker gasket, or will the blue Hylomar or Wellseal take care of it?

08-17-2009, 11:22 PM
Can you post a picture of the pitting?

08-18-2009, 12:57 AM
The cam bearing inserts I got were all identical (except for the front one of course, which doesn't come with the set) which means that one hole was unused on all but the last one. The extra hole in the last bearing is what feeds low pressure oil to the head & rocker shaft.

The holes lined up pretty good as I recall, once I got the inserts oriented properly. Seems like I even recall that one orientation was "close but no cigar"; but that was a long time ago and I'm not certain of the details.

My Fo8 seats also have some pits; a generous coating of Permatex #3 seemed to deal with it. But if you want to have them machined, I believe you can get thicker gaskets from Mordy Dunst.

08-18-2009, 07:25 AM
I'll get a picture after work tonight.

08-18-2009, 07:35 AM
I don't think that some pitting, or dimpling on the shoulders that the inserts rest on is too much to worry about. It's almost inevitable that the internal waterways and associated areas of a 45 year old engine block will have some corrosion. After having restored two of these blocks in the last few months, I learned a few ways to deal with it. The important thing to remember is that you're not preparing a highly technical engine for use in an F-1 car, but merely attempting to help out an old tractor engine live a few more years.

If you go to Lowes or Home Depot, go to the area where they sell the grinders, drill bits, saw blades, etc. There you will find some 4-1/2" Clean & Strip rust and paint removal wheels by 3M and other brands as well. These pad like discs attach to the end of your drill and look like some type of molded, web type abrasive. As I recall, with a little persuasion, the 4.5" disc fits quite nicely into and on top of the area you’re concerned about. If you work this disc carefully and evenly over these areas it cleans them up very well. You can then finish the areas off with the smaller abrasive type pads that screw into a little backing pad attached to your drill. These are also sold in the same area of Lowes or HD. With a little experimentation and patience, I was able to really clean and polish these little shelves quite well. These soft abrasive coated pads are great because they conform to the steel rather than trying to cut into it.


It's also very important that the oiling holes in the cam bearings line up. You need to remove the bearings and put them in properly. A "good" machine shop should be able to do this without trashing your present bearings, but a new set, especially since they're so cheap, would be worth it in my opinion. Be sure to install a new front cam bearing as well if the old bearings had a good bit of wear on them. Most places charge way too much (over 100 bucks) for the front bearing, which is actually more of a bushing. I found a place in Germany by the name of "Bastuck" https://www.bastuck.de/web/liste_classic.asp?untergruppe=11801&id_hg=11800 that sells them for about 18.50 Euro or about $26.00 US. The shipping charge is reasonable and is worth it especially if you get a few other things from them.

08-18-2009, 07:56 PM
Here is a picture of the area of concern. The block was hot tank cleaned and wire wheeled on the inside. I may be more concerned than I should be about this but it looks like a large area to me. This engine sat for 20 years before I took it apart. When I removed the head that cylinder had a film of oily rust on the liner walls. I think the gaskets failed some time while the car was sitting with the coolant still in it.

I did order a new set of bearings on Monday. The machine shop installed the bearings for me. I think the holes in the bearings were not correct, because the retaining bolts all lined up great. I will see what the new bearings look like from BPNW. The others were older stock from an other vendor.

Tab that is a great price on the front bearing. Thank you for the link. I don't speak or read German but the web site was still easy to use.

08-18-2009, 08:10 PM
I second Randall's suggestion. A smear of Permatex Aviation #3 non-hardening under the fo8 will seal fine.

08-18-2009, 10:34 PM
I think the holes in the bearings were not correct, because the retaining bolts all lined up great. Three holes, times two sides, means six different ways they can go in and line up with the retaining bolts. Only one is correct.

08-19-2009, 07:34 AM
The orientation of all the holes is correct. You can tell this by the fact that the holes are offset to one side. If you had them in backwards only one hole would line up and they would not be in the journals correctly. New bearings should be here Thursday then I will see whats going on.

08-19-2009, 07:53 PM

My block looked worse than yours before I cleaned it up, but with the method i described, I finally got it to look like this...


08-20-2009, 07:29 AM
Tab Very good results, what did you paint the inside of the block with?