New main & rod bearings after overheat?

[Matt Graham]

Experts,

I run a 1400cc '07 Busa in a Radical SR3. At my last race I had the coolant hose come off and pump all of the coolant out of the motor. Ran about 2-3 minutes that way before the gauges started to show funny numbers and I parked the car.

I let the engine cool, filled it back up with water, and ran it for maybe 30 seconds in the pits. Everything seemed fine, but I wasn't convinced and pulled an oil sample from the dry sump tank. After letting the sample site for an hour or so I could see a little coolant at the bottom, so figured I had at very least roasted the head gasket and decided to pull the plug on my racing season.

I pulled the motor out of the car and pulled the head off. Using a straight edge I can clearly see the head is warped. It's also already been skimmed once, and can't be machined true anymore, so I'll need a new head (and gaskets, of course).

My question has to do with the main and rod bearings. Having had a bit (and it wasn't really all that much in the end) of coolant in the oil, and having heated up the engine pretty good, should I split the cases and replace the main bearings? Only about 6 hours on this engine so far, and everything I can inspect without splitting the cases looks brand new. This includes the one rod I can get to that I pulled the cap/bearing off and inspected. I'm trying to avoid opening up what is basically a new engine even further, but at the same time I want to avoid spinning a bearing or throwing a (not all that cheap carillo) rod out the side of the case.

Thanks in advance for any/all thoughts and opinions.

-Matt

 

[GoldenChild]

just fix head and gasket put back together...flush the bottom end and drain then refill and fire..

 

[Commuta_Busa]

check the oil for any bearing material. If all looks good do what Goldenchild said. Have you thought about o-ringing the head?

 

[BA BUSA]

Doesn't sound like you ran it long enough to do any damage to the bottom end...just replace the head and get back to racing

 

[Matt Graham]

Thanks for the opinions guys. That's the way I was leaning, and it's always nice to be reassured. If I do throw a rod, I'll come hunting for all of you.

Commuta_Busa, I hadn't given any thought to o-ringing the head. I didn't overheat due to a bad head gasket, but rather a failed hose clamp (and my own idiocy for not checking it more often). Not sure how it would buy me anything, so perhaps I need some education.

Thanks again!

-Matt

 

[Mr Bogus]

+1 on the o-ring job... nice insurance... and to the .oRg

 

[GPW]

If your warping is heating related and nothing to do with detonation or head lift, then add to your cooling system to make it better. O-Ring's on the head are for those that are going to push cylinder pressures to the max with high compression motors, boost or NOS. If your not blowing head gaskets from excessive cylinder pressures I would not worry about it. I would add some head studs, a second cooling fan and a better coolant also do a compression check when you get the head back on. Just my 2 cents.

 

[Matt Graham]

GPW,

No worries on the cooling system. It's in a race car, you should see the size of the radiator in the thing. And the oil cooler is almost as big. It overheated because the coolant hose came off and it pumped all the water out. Also use only distilled water with Motul Mocool. Amazing stuff. I actually have to tape up the rad to keep temp in the water.

Already running the high strength studs, and a compression check and dyno time will be in the cards before the car hits the track. Sounds like o-rings are overkill. I'm not running boost or NOS, and as I said, the head gasket and cooling system all work just fine as long as all the hoses stay attached.

Thanks again!!

-Matt

 

[GPW]

GPW,

No worries on the cooling system. It's in a race car, you should see the size of the radiator in the thing. And the oil cooler is almost as big. It overheated because the coolant hose came off and it pumped all the water out. Also use only distilled water with Motul Mocool. Amazing stuff. I actually have to tape up the rad to keep temp in the water.

Already running the high strength studs, and a compression check and dyno time will be in the cards before the car hits the track. Sounds like o-rings are overkill. I'm not running boost or NOS, and as I said, the head gasket and cooling system all work just fine as long as all the hoses stay attached.

Thanks again!!

-Matt

Good luck going fast is a headache sometimes.