After running the Daytona Run on Saturday I had a little bit of oil under both motors. The area was directly under the belts and front area. More was under the Starboard motor than under Port.

We ran 65 miles each way, I never turned more than 5k and ran most about 4200. Rev limiters are set at 5300. There was not much oil showing( few ounces) and it was a little spread like it had come from the belts.

Someone suggested it was blow-by from the blowers running at speed for a while.

The motors are 675hp Chiefs with about 40hrs. on them.

Thanks,
Greg

I'm not familiar with blower motors, do they have separate oil for the blowers? Is the engine oil down at all on the dipstick?

I had the same thing on the port motor. Was the seal around the harmonic balancer. Replaced it and no more leak.

Thanks, VB. I'll check it out.

Cash Bar, I have the same problem on my port motor in a Formula 272SR1 which is very tight on space in the engine compartment, so I would be very interested in what you find. I suspected it might be coming from the lines going to the oil cooler but the crank seal sounds like a possibility.

Could be either seals on the fronts of the blowers, harmonic balancer seal, or like the leak I had on my engine, a little oil was getting by the key on the balancer and seaping out.
My leak looked very similar to what you have. Oil would dot the underside of the hatch, and when it was parked for any length of time, I would have a little oil sitting in the bottom pulley and in the bilge. An ounce at most total.

Yea ck the seals on the front of the motor .

Make sure your not building positive crank case pressure that might be pushing the oil out the front .could be the front of the oil pan I have seen it push it out there also.


On my race car it would push it out the seal on the gear drive cam seal . I was shooting a lot of NOS and there was some pressure in it


Rob

Cash Bar I have a 1999 28 Eliminator Daytona cat with twin HP500's and my passenger side motor is doing the exact same thing. I reached under the Harmonic balancer and it is dry so I would be curios to here the answer to your problem. Let me know? Thanks

Yes as stated dry it off and make sure it isn't the front oil pan seal. balancer lip seals don't usually go bad unless the balancer has a groove worn in it from many hours of use. If you replace it as dumb as it sounds you need to inject silicone around the balancer key as well because if there is a lot of crank case pressure it can even leak around there.

Roby

The engines ran great all day, oil pressure was good, and actually a bit high I think on the starboard motor. I suggested the pressure in the crank from the blowers was pushing oil from it somehere. It only seems to be in the bilge area, and not on the hatch or sides. It has a spray like patern as if it was slung from the pully area. I didnt crawl under them and feel if there was oil on the bottom of any specific area.