CooleyKing

iTrader: (1)

Okay so Jackson Auto Machine assembled the engine for the first time, they put there stage 3 rotating assembly in the engine. (good for 850+ hp) The car had many other mods and was tuned by batlground engineering. While the car was on the dyno it spun the #2 bearing. So the car was stripped and sold to me, but I had no idea the car had a spun bearing. I bought the car from an insurance auction thinking it was just missing parts from a theft recovery. I took the oil pan off and found the #2 rod cap was missing (I know they pulled the car down) So I disassembled the engine and had the crank looked at by a local machine shop, they polished the crank and I sent the #1 and #3 rods to a oliver rod distributor and they weighed the rods and sent me back a new weight matched rod for cylinder #2. The engine had a balance shaft elimanation kit in it. I put all new bearings back in the engine and reassembled the engine, everything went right back to where it was supposed to go. I put the engine and trans back into the car and drove the car for about 200 total miles since the rebuild. And then guess what the car spun a bearing again and it gets better, it was the #2 rod that spun a bearing. So I have disassembled the engine again and here is what im thinking.
A. The machine shop said that the crank would be okay being off 1/2 of a thousandth from were they polished it. The rest were perfect and the car is only around 420-450 hp at the moment. I put standard size bearing back in the car. I think they were wrong and that the crank should have been taken down 10 thousandths and I think it should have had 10 thousandths oversized bearings. But I took the machine shops advice and didnt have the crank turned.

B. Could there be an issue with the crank? because the car is getting plenty of oil and oil pressure.

Any other thoughts? Thanks in advance, James King

here is the link for the parts used; http://jacksonautomachine.com/index....mart&Itemid=12

Here is the cars pics at there shop and the dyno info; http://batlground.com/gallery/thumbnails.php?album=191

20gmr

iTrader: (7)

I was in a similar ****ty boat. I built my own motor and 3500 miles later the oil pump failed and it chewed up the main bearings. The crank was then turned 10/10 and polished. ACL ten over bearings were used and 500 miles later spun a rod bearing on cylinder 3...... the saga continues

blkmkIII

iTrader: (34)

- if they shop didnt have the crank flushed... no point, its all gunna come back out(metal)
-if you didnt flush the oil cooler,oil housing,oil lines,turbo === " "
-if your shop doesnt know what they are doing ------------" "
631-842-1973(evolution racing engines in ny) been in business since the 70s.
good luck
-sounds like this guy is slapping stuff together without checking any clearances.

LOVEBOOOST

iTrader: (2)

The first time it spun a bearing, I would be willin to bet it was battlgrounds fault. This is the shop in Atlanta, Ga right. My buddys sti spun a rod bearing on the way home from a tuning session. Ive heard bad things bout that shop!!

nos51

iTrader: (30)

if you didnt measure the tolerances when reassembling the motor you dont know what you had to work with in first place.motor might have been too tight from what it sounds like.also resurfacing the crank and using an oversize bearing is not recomended.i would find a good used crank or buy a new one and start from there...

JohnDoe1984

iTrader: (1)

At this point you have too much money and time invested in it to not get it right. I wouldn't give that crank a chance to screw you again. Get a brand new crank if you can swing it.

Fast_Freddie

iTrader: (50)

When the first rod took a crap, that contaminated your entire oil lubricating system. Without either replacing everything, or doing a huge flush, you are asking for trouble...

Tracy

iTrader: (1)

Wow. That's a bold statement. Not cute to spread rumors.

I wonder what changed: https://www.evolutionm.net/forums/7034601-post2.html

Jackson Machine

iTrader: (9)

One of two things has happened here.

A.) Whatever caused the issue the first time was never fixed. Be it a bad injector, vacuum leak on that cylinder, etc. Since you don't know the complete history of the car and there have been so many hands on/in it, assume that nothing is right. Inspect every single piece that is bolted on.

B.) Something was installed incorectly or a tolerance was not proper upon reassembly. What was checked before the new rod was installed?

Let us know if we can be of assistance. I've got some core cranks here, can get you a new one or take a look at what you've got and see if it's usable. It would be a good idea for you to take the shortblock all the way down and clean and inspect all of the components or you'll have more problems.

mchuang

iTrader: (11)

Hhahaha too damn funny, busted his *** lol.

MRfabolous

iTrader: (17)

did you reuse your oil cooler please tell so some people on here dont make the same mistake. good luck with your next motor.

billyblonco

iTrader: (1)

New oil pump, New oil cooler, new turbo, new head, new crank (never use a machined crank). So basically you need a new or slightly used motor.