hi i had a brand new 2.1l block, blue printed and assembled, did the 500 miles of breaking in then the tuning and now after about 1000 miles it has spun the #4 cylinder connecting rod bearing badly, what could have caused this?

i have researched that low oil pressure or debris could have cause this problem, but the oil pressure was good and i dont think it was a debris problem...

i was having crank case pressure issues with the dip stick popping off so i just zip tied the dip stick and was running without a catch can setup...

could running the engine without a catch can have caused this?

i am using 93 oct with 30 psi of boost and was revving to 9000 rpm's.

mods:

2.1L
manley connecting rods and pistons
acl race bearings
gsc s2 cams
gt35r turbo

 

Was the crank shaft oiling ports cleaned out? That's one thing I can think of for sure.

 

Did you replace the oil cooler? Just hot tanking it won't work. If you blow a motor, anything that oil touches needs to be replaced - Oil cooler, oil pump (case), lines, etc etc. If you didn't replace lines etc. You probably had the same thing that killed your motor the first time, kill it again. Bushcur did this with an oil cooler that they didn't replace for 3 built motors before they figured it out when evo's first came out.

 

my first engine is just fine, it has stock internals, i just changed the block cause i wanted a 2.1...

and no i didnt replace the oil cooler, my stock engine was running just fine on it so didnt think i needed too, i guess maybe not putting a oil catch can cause this..

more bad news, i just found that the brand new manley crank was also cracked in the #4 position...

 

Not unheard of for the manley crank cracking on the #4 journal..happend to several evos I know of. Stick with oem next time.

 

Look at the tune too. How you were running everything has to be perfect.

 

Dun dun dun...

Replace the cooler. DO NOT RUN ANOTHER NEW ENGINE WITH A USED COOLER.

If it's not in your budget to replace it, then block it off until funds are available.

 

Manley are forged in China

 

it was tuned by a professional...it was running good and AFR's were also spot on!

it was either that i was running a old cooler or i wasnt running a catch can setup with proper ventilation for the pressure's to eascape that cause this...

 

Manley cranks aren't forged in china , I'd call them and they'll probably ask you to send them the crank for inspection. What was the clearance on the rods / mains , bolts stretch ? Etc

 

I blocked off the oil cooler ports on my new build until the rings were broke in and had a few oil changes in the 1st 500mi before putting in a new cooler. I can see how no catch can could cause oiling issues as the high crankcase pressure on some builds will prevent oil from returning to the pan. I personally use a dual SM sealed catch can setup routing both back into the intake. Vented catch cans work but I don't believe they get the job done as well as sealed ones but seem be more popular due to looking nicer under the hood.