I want to check the main bearing clearance on this motor that I'm assembling. I know the clearance should be .0008-.0024"...but the thing I don't know is:

Do you have to bead a gasket on the block/bedplate surface when checking main bearing clearance?

This whole gasket thing never comes into play with rod bearings - and I've never built a bedplate motor, so it's never come into play with the mains for me. My guess is that I don't have to, but if someone could let me know for sure that would be great.


95 Eclipse RS : 5 speed
15.901 @ 88.34mph
Jeep TB writeup - http://www.dimensia.com:81/jimbo/JeepTBfor2gnt.html

Just assemble the bedplate and torque down the bolts to normal spec. Dont use any gaskets or anything. The anerobic sealant that is used gets compressed so thin, that its supposed to not interfere with any main bearing clearances..so just bolt it down dry, and use the plastigauge..

Cool. Thanks Matt.


95 Eclipse RS : 5 speed
15.901 @ 88.34mph
Jeep TB writeup - http://www.dimensia.com:81/jimbo/JeepTBfor2gnt.html

Just a little update - it worked out great. Nice new ARP main studs all torqued to 70. I got .0015 clearance on every bearing, so it looks like I'm good...on the mains at least.


95 Eclipse RS : 5 speed
15.901 @ 88.34mph
Jeep TB writeup - http://www.dimensia.com:81/jimbo/JeepTBfor2gnt.html

sweet :thumbsup So you like those ARP main studs?? I was debating of using them, but decided to just use the stock bolts..I figured the bedplate design, and 20 bolts holding it together would be enough haha..those would be nice to use though.. :)

They are really really nice. I've never used ARP studs before. I hear ya on the whole bedplate thing - its a beast. No wonder the crank can handle so much. There's not much room to flex embedded in the block...but I figured a high comp, over bore, turbo motor should have main studs instead of bolts. Check em out.

My main bearing clearance work area.


Bowling pins.


Each stud has an allen head in the top of it. Thats a nice touch.


12 point nuts...swimming in moly.


Heres a clean one. The washers are alot thicker than I was expecting.



95 Eclipse RS : 5 speed
15.901 @ 88.34mph
Jeep TB writeup - http://www.dimensia.com:81/jimbo/JeepTBfor2gnt.html

hehe yea, those allen heads in the top are new. i ordered my head studs today hehe. looks good!

damn! those are sweett! yep, they give you really nice thick washers, looks like the same as the ones on the head studs also..i'll tell ya, that bottom end ain't goin nowhere!

I will be bugging you for part numbers in the near future. Looks good :thumbsup

metal jim go buy 5 big scotch brte pads and remove that surface rust!!!!!!!


i had it on my motor that is why i was drove to polish it all out but get that out u dont want that in your oil.....!


but the studs are nice i agree ARP does their homework...

u will want to get a plastiguage to check the clearance if u dont already have one...

Bill

p.s. be very careful dropping the crank in and use moly lube when u really assemble it u know where i am if u need help...

Yeah Bill, it is kind of ugly in there. But the machine shop that I'm using(Jess Miller http://www.jessmillermachineshop.com/ ) has this block cleaner. It looks like a shower stall, but it's got high pressure nozzles on the sides and a turntable on the floor. I was gonna see how well it cleans up with that thing before doing anything. I'm having him clean it after he does a line bore check and bore matches the cylinders to the pistons.

And yeah I already plastigauged the mains. They came to 1.5 thousanth clearance on every bearing - a nice middle of the road tolerance. I also checked the crankshaft end play with feelers - came in at 7 thousanths - just a touch above middle of the road tolerance, but good.

So the main bearings look good, but I'm still waiting on pistons/rods. I hope they come in this week.


95 Eclipse RS : 5 speed
15.901 @ 88.34mph
Jeep TB writeup - http://www.dimensia.com:81/jimbo/JeepTBfor2gnt.html

good deal yea make sure the block cleaner get that or bust out the scotch brite it wont hurt machined surfaces unless u realy try to witha scotch brite pad...

Bill