2003 Evo 8 - Under 90k miles - 4k miles on New Engine -> Rod Knock

I had a stock short block installed at a semi local reputable shop. I think they have 1 year warranty on their installs. The new engine is about 1.5 years old, only 4k miles, and my engine is rod knocking (mostly verified by my mechanic friend). The shop told me to run 20w-50 oil in the engine.

The day that this happened I changed the rotors and brakes and put in 10w-30. Then went to do a break in on the pads, I had to accelerate to kind of hurry these tests because if I didn't traffic would catch up too quickly, so I would do some 10-60mph accelerates then do the 60-10 stops outlined under the bedding-in Street Performance Pad section in the link below.

http://www.stoptech.com/technical-su...-system-bed-in


On the last run (20th) the car started making the rod knocking sound... I limped it home, 3min drive and turned it off. I ran in the house to take a **** then came back out to look at it and coolant was on the ground, and was overflowing out of the reservoir... I turned the car on and the temp gauge appeared pegged for 2 seconds then rapidly returned to normal temperature. The car never emitted any smoke during or after the brake bedding process, so I'm not sure if it was actually overheating or not as I was not watching the temp gauge during this time.

I didn't call the place where I got the "New" engine installed, yet. I figured I would post here first.

-Thoughts or comments on what happened?

Thanks.

 

I'm not an expert by any means, but it sounds like you using the lower viscosity oil, mixed with the constant go and stop add in the overheating and I think that's the solution.

Bearing tolerences were probably set loose and they wanted the thick oil to account for that, you used thinner oil that could possibly damage the bearings if it got hot (thin) enough. The engine overheated, (air bubbles or blown HG?) the oil got too thin and the engine was being thrashed on, so it ate a bearing. That's what I'm thinking.

However a blown headgasket and water getting into and causing some kind of hydrolock to bend a rod could happen, but that's unlikely.

 

Was it a stock short block or built??

 

It is a Stock 2.0L short block straight from Mitsubishi. Sadly it is out of the 1 year warranty offered from them. I'm thinking about getting the engine diagnosed unless I come across a good deal to sell it as is soon.

-I could just trade it in and get out of the car game... I hate to because it is a great car and in good condition other than the engine issue. I even started looking at getting a used 2013 Honda Fit... Which is a far cry from an Evo. The Honda dealer was offering me 10k for my car in good condition, but I'm not sure how far that will drop with the engine issue.

-My buddy said I can trade the car in as is for $7500 at the Chevy dealership, but then I'd have to get a Chevy and with my budget a cheap Chevy at that... Unless I can find another make car on the lot.

I'm just not sure if I want to:
1. Trade it in.
2. Private sell it as is.
3. Fix it up then private sell it.

-Other than posting in the cars for sale section on these forums, any other recommended sites to post my car for sale?

 

Why would they tell you to use 20w50 in a stock engine??
What part of PA are you from?

 

Stock engine needs 10w30. You probably beat up the bearings on cold starts due to running the 20w50, and it simply finally decided to let go.

 

-I'm from Western PA.

-Honestly I didn't drive it all that much in the Winter, hence only 4k miles in 1.5 years. I babied it until the engine reached normal operating temperature, as you do with 10w30 anyway. I wouldn't think it would damage it to that extent, but I'm not an expert so who knows, maybe that is what caused it... Unless the bearing wore that severe within those few minutes of bedding in the brakes... Or maybe a cooling system failed at the same time and I didnt notice, but I never saw any smoke/steam or anything emit from the hood/engine bay nor did I smell anything irregular.

 

True^ 20W50 is heavy, especially in cold weather.

 

Had another buddy look over the car and he pointed out that the oil cooler was missing. Looks like the place that replaced the short block also upped their profit by excluding a new oil cooler into the quote. I'm not sure if that is a common practice with a new short block and I'm not an expert, but that might be a reason for the overheating. If that is the true reason for the overheating then sad days.

 

The oil cooler missing should have little to no effect on the temp of the engine unless it is being tracked. Many people, including I, have ran no oil cooler with no problems.

 

I was sent 20-50 Brad Penn oil from a shop for my stock block car also. Hmm. Maybe I need to switch.

 

The engine overheated because you had a bearing problem(metal on metal friction). The engine relies on oil to cool almost as much as coolant and if you cook the oil by driving a rod knocking engine 3 miles, you might as well put a torch on the block. When you continue to drive the engine, not only is the oil well beyond its specified temp range, but your taking bearing material with it to go throughout the engine and pretty much destroy everything. Cam journals, crank shaft, pistons, bores, cam lobes, oil pump, ect.

10w-30 is good for a completely stock car. A jump up to a 40w is a good idea. The oil film needs to be strong to protect from metal on metal contact. I highly doubt the engine will be warrantied. Its was a brand new engine, they just installed it, and its outside its time period.

 

Well how I was bedding in the brakes was more or less like an autocross type stress on the car. I know there has been discussions on here about leaving the oil cooler on the car for autocrossing. I would have wanted a new one on the car if given the option, but I wasn't aware that it would be deleted.

 

I would switch it out, just stick with Mobil 1 10w-30.

 

This was all done on 10w-30 and there was no rod knock sound until after the last run, so really no reason to think that the car wasn't running perfectly before that; however there could have been prior undetected damage from the 20w-50 in the Winter. I just figured with the back to back rapid acceleration, combined with no oil cooler, and the cooling system on the car being 12 years old (aka doesn't work like 100% new) contributed to it overheating and deteriorating the bearing metal further to the point of audible rod knock.