Roger Z06

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I am building my LQ4 right now, I have an Eagle 4.00 crank with clevite standard bearings. I just had my block bored and lined bored(I am pretty sure they line bored it) to go from 402 to 408 .030 over from stock. Anyhow I was putting my short block together tonight and I greased up all the main bearings put all of them lock to lock including swapping the #1 main "backwards" like it is supposed to go. Then I hand tightened the ARP studs and put 60 inside and 50lbs of torque on the ARP nuts. The first time I couldn't turn it over with a breaker bar. So I stared to loosen everything up and tried turning it over being slightly successful. Point being that now after I have finally got it turning over at somewhere around 50-60lbs of torque I have a problem. It should be able to spend by hand and spin a little after I let go. #2 and #4 main bearings have a lot of wear on them from turning it over by handI am think one of three problems...
1) When the machine shop line bored it they did not tighted down the mains all the way and it is off.
2) They warped my crank by laying it on the ground for too long horizontal instead of vertical
3) They somehow gave me the wrong/defective bearings.

Any input/suggestions, has anyone else been here before?
Thanks, Roger.
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lucky131969

Plastigage the mains....

Roger Z06

I have plastic gauge, I just know that if I put in under the mains it will smush the hell out of it seeing as it has already worn almost to the copper on my main bearings... It is rubbing on the sides.

lucky131969

Ok, so did you compare the journal size of your crank to the main bearing size?

Either way, sounds like it's back to the shop.

Bill Curlee

WOW! Before I even read Luck131969's reply, I was thinking "Stop right where your at and take it back to the machine shop!



Please let us know what they say and find.

BC

Roger Z06

What do you mean, measure my main bearings with my crank? They are both standard.

motorvation2go

By "sides" I think you probably mean edges of bearing shells?
Aftermarket cranks are often made with radiused fillets (stronger).
This can and will cause edge contact.
My guess is that you will need chamfered bearing shells.
Also, the crank should have been miked by the machine shop to ensure proper shaft diameter. Stuff must always be checked before assembly! Just normal practice.
Eagle can be pretty 'spotty' in the dimension dept.
Like Lucky says... back to the shop (or maybe find a better one).

ctusser

So Is measuring them upon assembly to double check. Mistakes happen.

warriorp

not bashing...but pay a pro to assemble the engine...you will come out ahead in the long run...there is a long list of no no's ive already heard...to properly inspect your bearing clearance you should torque the main caps down with out the crank and use a dial bore gauge to measure the difference...looking for about .0025"-.0035" clearance...plastigauge is ok but not quite as accurate and should be used before you oil the crank for installation...if copper is showing on your main bearings they are already ruined...sounds like you dont have proper clearance or a main cap on backwards...1-4 "point" to the rear and 5 towards the front....good luck

lucky131969

You need to take it back to the shop...


Good luck...

Roger Z06

Yea well I agree they are obviously shot now, and I need new ones. I am just saying that is how hard it is rubbing on the crank, is #5 (the one that is on "backwards") in the front or rear of your engine?

Roger Z06

All of these parts are the exact same parts that came out of the motor when it was running fine(tore it apart because of washed out rings) and I had to bore it to 408 because of excess damage to cylinder walls. All I have is new Diamond pistons.

warriorp

look at the pointed ears on the main caps in the pic and aline them like that....i forget the tang orientation...ill look in the morning when i get to the shop if you need...the ears point to the rear 1-4 and to the front on 5...the ear im talking about is the part of the main cap that touches the side of the block and the side bolts screw in to...good luck

Steve D.

Bearing tangs in the block are facing the driver's side, the tangs in the cap face the passenger side of the block. Most engines, including the small and big block Chevy engines have them facing each other. The LS blocks are different with them facing opposite sides of the block.

Get a new set of bearings, get the caps on there the right way around as shown in the photos then check the bearing clearance preferably with a dial bore gauge which is considerably more accurate than Plastigauge.

Aluminum block main bearing clearance should be .002" nominal (.00175 = .00225) for street use with 5W30 oil. If you get the clearance .0025" or greater, you will have problems with low oil pressure when the engine is up to temp.

Blue Blood

Did you mark the bearing caps so that they all go back in the same location and correct direction? If not...... back to the machine shop

Roger Z06

They are stamped 1-5 so you are saying 5 is supposed to be at the front?!?!? I have it backwards if so.

Okay I have been looking at a LOT of pictures of LQ's and I have seen that 1-4 face the same way starting from the front or timing chain side facing towards the rear. 5 is supposed to be backwards, but I have 1 backwards and 5-2 facing towards teh timing chain. I am not sure how I can change this seeing as they have to go "Lock to Lock"... I probably need to look at it tomorrow.

Roger Z06

Also how hard should it be to turn over the crank with no rods or pistons?

ipuig

By hand assuming your are lubricating the bearings and your bearing clearances are set correctly.

SDPC

The pictures are right. 1-4 all face the same way and 5 is the opposite direction, it sounds like you installed the caps incorrectly. I think from what it sounds like the you have 2-3-4 the wrong direction, Do you have "H" or "HN" bearings, or are you using "P" bearings? It will say on the box. Sounds like you also might not have narrowed main bearings for your aftermarket crank.

NicksZ

Also make sure they line bored the mains with the ARP studs... not just the bolts. The clamping force is different and needs to be accounted for...