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DISCUSSION => Engine + Driveline => Topic started by: speedy8ty7 on February 06, 2009, 01:55:14 PM

Title: m47 Main cap
Post by: speedy8ty7 on February 06, 2009, 01:55:14 PM

i was doing a little research on the m42 and read about the 180* thrust bearing. i was wondering if a m47 Main cap would work with the m42 block therefore getting a 360* thrust bearing

any help would be greatly appreciated.

Title: m47 Main cap
Post by: cecotto on February 06, 2009, 02:37:23 PM

never mix and match caps like that.

They are linebored/honed together with the block. And as such unique to both the block and placement in the block.

If you read my buildup thread, i supplyed numbers on the bearings to use. Those will provide true 360 degrees of thrust bearing.

Title: m47 Main cap
Post by: peerless on February 06, 2009, 05:29:40 PM

You can also have your original M42 main caps machined by Metric Mechanic to accept the early M20 bearings. You get the 360* thrust bearing AND 360* oiling grooves.

It cost about $125 to have the caps done through MM. I have had them do 2 sets for both my rebuilds. I am sure you could find a competent machinist locally to do the same, probably be about the same price.

Oh ya, also you can go with different main caps from a different engine, BUT you will have to have the block line bored and honed. Thats about a $150-$200 operation. And no, I do not know if the M47 caps would work, not familiar with that engine.

Title: m47 Main cap
Post by: speedy8ty7 on February 06, 2009, 06:22:59 PM

Thanks for the help i think ive got the info i need

Title: m47 Main cap
Post by: forrer13 on November 06, 2009, 10:14:51 AM

I am trying to build 1 running engine out of 2 junk engines and am wondering if I can use the crank and main bearings out of block A (the bearing and crank surfaces look good) and put them into block B using the pistons from block B and new con rod bearings?

Title: m47 Main cap
Post by: kowalski on November 09, 2009, 06:15:50 PM

Quote from: cecotto;66021

never mix and match caps like that.

They are linebored/honed together with the block. And as such unique to both the block and placement in the block.

If you read my buildup thread, i supplyed numbers on the bearings to use. Those will provide true 360 degrees of thrust bearing.

you could get the block line-bored again. I've done this to swap caps on other motors, so I don't see this being a problem.

Title: m47 Main cap
Post by: kowalski on November 09, 2009, 06:19:04 PM

Quote from: forrer13;80994

I am trying to build 1 running engine out of 2 junk engines and am wondering if I can use the crank and main bearings out of block A (the bearing and crank surfaces look good) and put them into block B using the pistons from block B and new con rod bearings?

you want to swap used main bearings from one block to another? they're not that expensive man....

Title: m47 Main cap
Post by: bwawuz02 on November 10, 2009, 10:52:59 PM

Quote from: cecotto;66021

They are linebored/honed together with the block. And as such unique to both the block and placement in the block.

So i misplaced the main bearing caps during disassembly, is there anyway to get them back in the right spot without having them line bored again?

are the markings on them helpful like the camshaft bearing caps?