Groove in Main Bearings

[joelittel]

Are the two bearings that do not have the groove supposed to go on the ends (crank pulley & flywheel side) of the crank?

[DieselSpider]

All I found in the engine rebuild section of the manual was a notation to match the numbers on the bearing caps with the numbers on the block and a reference to notches indicating that starting from the front you use the cap with no notch and then progress from 1 to 4 going back.

Memory from other 4 cylinder engines is that the solid bearings go front and rear with some having pressure relief notches to direct oil back into the crankcase to minimize seepage through the seals. The download I got was not done in gray scale so the pictures are not very clear and do not show the placement of the bearings with the grooves.

[joelittel]

Thanks diesel, that's helpful.

In Croft's book, the Building Up The Block section, he mentions that the "large" bearing goes on the center journal. I don't recall exactly how he phrased it, but it's similar. I'll have to check my new bearings when they come in tomorrow to see if one is in fact wider than the others.

[aj81spider]

I'm the farthest thing from an expert, but the service manual for the later Spiders says (page 10-52) the center bearing is the one without the groove and 1,2,4, and 5 all have grooves. I have an electronic version if you PM me your email address and I'll email it to you.

[So Cal Mark]

what do the thrust bearings look like? I'd be really concerned with the way your mains look. Those dark/shiny spots indicate either a line bore issue or a crank that's bent or not flat on the journals

[joelittel]

PM sent, many thanks for the reference material.

[joelittel]

The thrust bearings are new and look new, no dark spots, no scuffs. But just to be sure I'll check them again.

The connecting rod bearings looks good too.

One step forward, two steps back though. I do have a crank that worked great in my stock block, maybe I should plastigauge it and put that one in instead.

Also of note, the bearings and crank combination in question was used for 100 miles with incorrect tolerance. I'm to blame for it and have been paying the price for a few weeks now. Could the dark and shiny spots on the mains be caused by .003"+ clearance?

[So Cal Mark]

that's about double the clearance I would want. You'll have low oil pressure with that much clearance

[joelittel]

Thanks guys, for all the input.

Yep, low oil pressure started this whole mess. But I've learned so much in the process of fixing my issues that I'll dare to say it's been worth it.

When I built this engine up I rushed the final stages and made some assumptions that I wish I hadn't. I should have taken my time and gone through it twice but my wife wanted it out of the dining room.

The best part of this entire experience has been the help I've gotten along the way. I truly hope that I can return the favor for someone in need down the road.