I believe that was the rear counterweight kissing the#4 main webbing,another issue different to the thrust bearing
Tom Righter, I have a 4 Toms here right now, one is a freshen up and I can see what Roydens guy is saying. The Radius on the crower crank is too wide causing it to catch the edge of the main bearings. I ran into this on a rebuild that another builder did and it was the same on that 470 also.
Yes, 3 on them are 3 inch mains. It had Clevite's in the one, it seems on the one block that its only on 1 and 4 mains and its on the cap side only. It will look closer tomorrow.
Being that it looks like its only on the cap side, the bearings in the block side look ok I am thinking its a alignment issue but I really need to investigate with a closer look before committing to the findings.
I have the 3 inch main and I am using king race bearings. I did not notice a problem but I will look more closely before I do my final assembly.Thanks for the heads up,Tom
Tom, Are you going to continue building the engine you have for sale? Will it still be for sale later or is that done? Picked a cam and heads yet? Just curious... Thanks, Philip T.
I have all the short block parts except for the camshaft which I’m finishing the cylinder heads now,once I get the flow numbers I will pick a camshaft and put it together. Didn’t seem to be much interest on selling it so for now I’m finishing it.Also waiting for the new cast head to come out.
It looks like a indexing issue, its a easy fix. Its mostly on the cap side on 1 and 4. It also has a odd wear pattern on the bearings that I need to sort out.
It’s very important that the caps are cycled on and off at least four to five times prior to the final line HONE as the sizes will change.Also be sure to chamfer corners on caps as they are sharp and will dig into the block and will not seat properly. when using a aftermarket Race or Performance crankshaft like crower be sure to use bearings that have a large chamfer for clearance. Not to say that there is not a alignment issue with the caps I have not looked into that yet,but just good info.
Just looking at your pictures of your bearings I can see that the king bearings definitely have a larger Chamfer for crankshaft clearance
It didn’t fit tight on the Cap,it fit tight in the block,you would literally have to beat it off with a mallet or something soft against the bearing shell and you had to hit it pretty hard to get it to come off!I Worked it out now so that it slips on and off with just light pressure with your hand.
Not a problem Tom. My thrust bearing fit a bit tight onto the cap so I thought that may have cause an issue.
Good thread... getting this info out there will help the community, and it explains why I charge $500 more to put together one of these, vs an iron motor.. it's a lot more work. King HP bearings are the only way to go with the 3" mains. Watch for it thrusting on the number 4 cap with a 3.25" main and stock crank, and with the 3.25 mains, pay careful attention to the rear seal fit. I was hoping they would have tightened up the machining program by now, especially on that center main.. maybe in the next run.. JW
I am just starting a redo on someone else's build. I would say the thrust is too tight because of the wear pattern and it took a big bar to remove the old bearing. The bearings on the cap side is staggered/offset to the bearings in the block hence why I think the bearings on the cap side are are riding up the radius. I will try some different bearings also to see if that helps.
