New 4.6L stroker build

[strokedzj]

was this an isky cam this time or a comp? and are you running the exact same bearing brand every time? if so maybe a defective batch of bearings? or defective batch of cams? i know it sucks to throw away all that time/money by switching blocks but i think you'll be a lot farther ahead in the long run especially seeing how this one is obviously jinxed.

[SilverXJ]

Its a clay smith cam. Last time, IIRC, we used speed pro. This time durabond. From what I have seem most cam bearings for the 4.0L are made by durabond.

[92tank]

well one thing thats for sure is that you will be able to pull engines like a pit crew can change tires!

i know you have all that money into this block with the machineing and all but you have to draw the line some where

wish you luck with the next one

[strokedzj]

i have to agree with 92tank on the new block idea. it seems that the block you have only wants to eat parts.

as for my engine noise i guess i'll live with it for now, the machine shop don't have the part number for the valve spring that was used. he also said i shouldn't be running synthetic oil which makes no sense to me when i run it in everything else and have had no problems. i will try what comp said and use conventional oil for a bit and see if the lifter noise quiets or goes away. if it doesn't i will just go back to syn and save for a new cam/lifter/spring setup.

[SilverXJ]

Even I have doubts about another block as all the three i have had all exhibited that knocking noise.

[strokedzj]

low end knock or high end? so you've had 3 different blocks? i was thinking all these builds were on the same block, guess that's what i get for not reading the entire post!

your working with a late model block though aren't you? like 99 up. to me those seem to have issues even stock. and it's not to easy to come by a good used one at least where i'm at. a good used 4.0l from 99 up is at best 1,000 but more commonly 12-1300. and it looks like a bear to swap a early 4.0 block into the late models.

[SilverXJ]

low end knock. I never really figured it out. Hesco though the crank was ground with a taper, so that was fixed. Noise was still there. One person I have been talking to mentioned cam bearing noise, which sounds like what I have.

[strokedzj]

low end knock indicates main bearings to me. i can't recall ever having a cam make noise, just worn lobes.

[SilverXJ]

No, it wasn't main bearings or worn out lobes. It wasn't anything in the valve train, or rods, or crank, or timing chain, or oil pump. Only thing left is the cam.

[strokedzj]

strange. that's wild that you had the same problem/noise in three seperate blocks with all different parts.

[SilverXJ]

I am pretty sure that all the blocks I have include some sort of issue with their cam bearing tunnels. Every one had that knock that couldn't be figured out, even the ones that didn't eat the bearings. I took a look at a block that wasn't worked on by machine shop and still had the cam bearings intact. It had that knock as well. That block has about 5000 miles on it. All the bearings showed some wear, not torn up like the ones in the current block, but still more wear than I would expect for 5000 miles. The #3, which has the ID groove was nearly down past the groove.

[92tank]

this issue sounds to me like the newer blocks are having cam issues im wondering if you could go with an older block that would not be from the years you are trying to build. and then put all you sensors it that older block. the 92 block that was in my jeep from stock had over 255,000 miles on it and had no noises, no doubt a little blowby but no knocks. and the 95 stroker block had 183,000 miles and had no knocks and all the bearings were good yet. might be worth the try

[SilverXJ]

I've found someone that can hone/ream the cam bearings. It would be cheaper to do that than to do all the machine work on a new block. And I get bearings custom fit to the camshaft. I'll probably go that route as I don't think the coated bearings would reduce the clearance on #3 that much.

[strokedzj]

you would have quite a bit of work getting an older series block to fit anyways. good luck on it. hopefully you get more than 1000 miles out of this one.

[SilverXJ]

I'm dropping the block off this Saturday at Motion Machine in Danville. Its the closest place I found that will resize the cam bearings.