Hey guys, i'm gonna do my best to give every detail about my rod bearing failure in order to figure out why this occured. I'm hoping that we can discover a reason so that this won't happen again.


Durring the time that this car developed barly noticable noise (i'm paranoid and always listen closly), i was making some hard pulls on the highway against a dsm buddy of mine. It was about 50ish degrees out (f) and the car was running at normal temps & my high boost setting of 24psi (70trim t3/t4 garrett) when just after the last pull, i felt like something just wasn't' right. Upon decel, i notice an audible difference, extreamly minute but i notied something. Then about 3 miles from that as i was approaching the final hill to my house i heard a knock and notice that the car was getting a little warm. It hit 210 degrees (f) and i pulled over to let it cool down. I noticed that my fan wasn't running so i shut the car off. Figured i'd just let it cool down and then drive up the hill and park it in the garage.

I knew something was wrong and was pretty sure that it was a rod bearing failure, i've heard this noise before. It was about 1000 ft. away from my drive way so i baby'd the car there.

This morning i pulled the pan and discovered rod bearing failure on cyl 4










Here are the pix of the NGK BKR7E spark plugs (Gapped at .020)

Cyl 4 (the one with the bearing failure)


cyl 3


cyl 2


cyl 1



This is a pretty new, fully built motor.

Dart Block 2.0
9.0:1 CP pistons
Eagle Rods
Eagle Crank
GSR Oil pump

Bearing Clearances when i built it:
This engine runs Castrol GTX 20w50 Oil



This is the dyno sheet from last week (Mustang Dyno)



This is the tune that the car had on it durring the failure:

Fuel Map Non-Vtec


Fuel Map Vtec


Ignition Non-Vtec


Ignition Vtec



If there is any other information that is needed to help figure out why this bearing has failed, please let me know. I'm going to fix the results but i'd really like to fix the problem that caused this so that i don't have to worry about it happening again.

Thanks for the help and your time, i know this post is long but i wanted to make sure i had everything here.

 

Pics of the rod? Dont most of the rod manufactures recommend .002-3" on the oil clearance? Almost looks like you starved it for oil how it melted like that. Was the oil full? Oil press was good before?

Also did you stretch your rod bolts on initial install?

Edit: Oh **** i just re-read the title, Im def. not a pro

 

why run 20w-50?

im not a tuner so i won't bother what i think about your maps

what bearings were they?

 

I would not reuse that crank. Are you sure there wasn't an issue with the crank in the past

 

Too tight of oil clearence and running 20w50.

 

rod looks fine. No sign of discoloration, no grooving, nothing appears to be wrong with the rod at all.

I agree with the statement that it looks like it was starved of oil but at no point did my gauge show sign of low oil pressure, nor did the oil idiot light ever come on durring this failure.

As far as the bolt strech upon install, i didn't have the means to do that, so i used my torque wrench and torqued them to ARP's spec, just like the last couple motors that i've built in the past. No I've not had problems with that meathod in the past.

 

I was under the impression that i should run thick oil like that with the larger main bearing clearances that i was running. Was i wrong?

recommendation of correct oil to run with my clearances ??

thanks for your input.



I used this crank in a different motor before and had no problems with it. Before i decided to use it in this motor, i had my machine shop check it out to be sure that it was in good shape and they assured me that there were no problems with it...

 

If you see something that looks incorrect in my maps, then please bring the information forward. I'd much rather be wrong about something than cost my self more downtime & money in the long run. I can admit that i don't know everything!

Bearing were all ACL race bearings.

 

The motor messing up didnt have anything to do with the tune.
I would use a stock honda crank of possible.

also 5w30 is what I break my motors in on....

 

what clearances are in those motors tho. I mean shouldn't i be concerned about that. I'm running larger than stock spec clearances here.

 

did you break everything in correctly ?

 

correctly is a loose term when refering to break-in as there are many different meathod's.

This motor had the laptop hooked up upon first startup and i adjusted fuel settings right off the bat, so it wasn't abused in that aspect. Then this thing saw 300miles of street driving before the dyno. the tune was dead on for low boost.

It was then put on the dyno, i iron'd out the timing and then continued to tune at a higher boost level to make some more power.

Drove it on & off for about a week (100 miles worth) before this mess.

and here we are now.

 

20-50 oil is to thick for a honda engine.

 

my clearances are all on the big side also and i've been running 5w20 on this build with perfect oil pressure for 20k+ miles so far with zero issues . i broke the motor in with 10w30

 

20-50 is the way to go. Just listen to the guys making power

 

20w50 isnt too thick.

 

dont you think it looked like the bearing was oil starved , or is there somthing else could cause the melting of the bearing ? those are both serious questions btw lol

 

This is getting very similar to my issues I have been having as well. For some odd reason my built gsr was only making 5-10psi period starving it of oil, and leading to bearing issues like yours. The crank is being sent in to be machined up, and I think my builder said oversized bearings since my clearance was on the bear minimum after plasti gage.

 

As a engine builder i believe you starved the rods at high rpms!, that oil was most likey to thick to circulate through the crank, 10w-40 would of been the thickest i would of went, was the oil galleys in the crank cleaned out? not many engine builders do that. what was the clearence on the rod bearings? was the block assembled by Dart?

 

well according to his papers he posted the oil clearances were 0.0015 and in my factory service manual for a GSR 0.002 is specified as the service limit

 

20w-50 was to thick for those rod bearing clearances. 20w-50 would be more acceptable if your rod bearings were clearanced at .002, and I wouldn't even use it then.

 

If anyone has a chart that shows what viscosity oil to use for what size clearances and it's produced by a reputable company. Then someone please show me this. That would put an end to all this rubbish about 20w50 being two thick for my motor.

This engine gets warmed up to operating temps before it's driven. It's ran hard when it is driven. Then it cools down before putting it away. Only taken out in the evenings or weekends.

Lets move on and look at other senario's as well.

Thanks for the input thus far.

 

in for the oil vs clearances chart!

 

what clerances are recommended for arps on a b16a and whats the tq?

 

Make your own thread jackass