Jdm03

OMFG!! This is really pissing me off lately. I have a d16z6 that I'm building. (I DONT CARE IF YOU HAVE SOMETHING TO SAY FOR SOHC) I have a reman. crank from o'reilly's auto parts store that came with new main/connecting rod bearings. I recently had .25mm for main bearings to start out with. Measured them with plastigage and this is what i get: 1,5= .002" 2-4= .003" which is to small for oil clearance. measured the thickness and came out as .085"

Did this a couple times to verify and had the same result. Ok, so then I went to the auto parts store and got .50mm bearings. Measured the thickness as well and came out as .090". I figured, that'll take off .01" off my clearance making it in spec. tried them out and the god damn crank wont fall in flush to the main bearings

Also I had the guy from the auto parts to order the same kit to verify if the bearings are the same ones I had before (.25mm) and come to realize that it comes with the .50mm, so I guess they threw in the wrong bearings to start out with in the first place.

What the hell am I doing wrong??

Please, I need help getting the right bearings. this is really frustrating me.

Jdm03

the brands for bearings are kings

Jdm03

bump.. i don't want to make the wrong choice

NotAJDMFanBoy

Actually, a lot of guys are running about that for oil clearance, or I think even tighter, it's been a while but I think .001 to .002 is preferred.
.5mm is .01". So going from .003 and reducing that by .01 would be .007 too small, why it won't fit.

The issue with aftermarket bearings is that if you don't like your clearances, you usually don't have any other choice than to buy OEM bearings. For OEM, standard is green and they go up and down in size by .001 I think. You can mix one size with one size up or down to get your clearance, but no more.

King and ACL bearings are fine bearings, they just come in standard and .001 oversize, and the really big oversize. I have an OEM crank and running regular King rod bearings and ACL main. A friend of mine was running King.
And because this comes up so often, bearings don't have to be changed if you rebuild. They can last 300,000 miles, so they're either good or bad. The journals ride on a layer of oil, so there's no wear except at startup, and then if you spin a bearing...it's shot.

Jdm03

when the motor was torn down piston #4 had spun a bearing and tore up the crank and the connecting rod (which i replaced).

when i got the .50mm bearing, i tried em today and check how they fit and all. finding out the the crank is not sitting flush at all! i would have to tap it down with a mallet and the main bearing cap don't sit flush to the block as well.. its irritating. i honestly don't know what to do at this point.

Jdm03

There's a small gap between the main cap to block. And if I tap it more with a mallet nothing really happens. The other way to bring her down towards the block is to put in the main cap studs and screw them in, but doing this would probably cause stress to the bolts making them stretch and causing more problems later on.

I literally had to use the mallet to remove the crank off the block. This is another indication of how tight the crank was.

Jdm03

any other suggestions?

NotAJDMFanBoy

With the thinner bearings, the crank went in. With the thicker (.90 thick) bearings, the crank won't fit. Right?

On the SOHC engines, I'm seeing the main oil journal specs as .0007" to .00014" and a service limit of .002" for 1 and 5 (outter journals) and for the inner (2, 3, 4) journals, I'm seeing .0009" to .0017" and a service limit of .002"
For the rod journals, .0008" to .0015" and a .002" service limit.

So, your .002 to .003 clearances are actually too big. And going from .085" thick bearings with a .002 clearance, what will happen if you get two bearings that are going to reduce the diameter .005 each? You had .002" clearance, and removed .01" of clearance. It's just too tight. You would need .008" more clearance for the bigger bearings to work.

NotAJDMFanBoy

If you don't have a Haynes manual at least, and don't understand what I'm saying here about clearances, then get help. Some people understand this stuff, some people don't.

strategy400

Although I can totally relate, pissed is not good for working on engine internals. Take a break.

Jdm03

@ strategy400: yea man, i honestly can not concentrate when im pissed off.. i left it alone yesterday and start out in a better mood.

@ NotAJDMFanBoy: i thought of it all day long today and came with a resolving conclusion.

the bearings that i have right now are WAY to big for this.. not giving 2nd thoughts or nothing. did all my math during work, and if you think about it, .003 is the oil clearance from my previous bearings (.25mm and the thickness were .085").

now my current bearings (.50mm and the thickness is .090", which is .005" bigger and adding the second bearing that equals .010"), giving that my oil clearance would come out to -.007"..

i can't believe i did such an idiotic decision and not thinking through this twice..

the only way to fix this is to add another .001 to the .25mm bearings, and that way it will put me in spec. and will make them .086" thick. which brings me to this question, where can i buy them?

and just in case, im gonna do the right way in measuring everything so that way no mistakes will be caused again