I goofed drilling piston port hole

[flphil]

Although I have done it correctly probably 20 times, I drilled one of the holes in my Honda Elsinore's (Wiseco) piston just slightly to the side of the exhaust bridge.

I am assuming this can result in a loss of pressure for intake into the crank. Wondering if anyone else has experienced this and if it is necessary to order a new piston?

 

[High Lord Gomer]

Since it is below the rings, it shouldn't affect the negative pressure during intake, and I don't think it will let much more out on the way down than it would if it were lined up with the bridge. The only danger I see is that the bridge won't be getting enough lube.

If we were talking about a 93 CR, I'd say drill a hole where it should be and let it go with two. Since it is an Elsinore, I'd buy another piston and be more careful when you mark it before drilling next time.

 

[tracetrimble]

sorry to hijack, but is this an exhaust bridge?

<img src="http://img.photobucket.com/albums/v280/tracetrimble/exhaust.jpg" alt="Image hosted by Photobucket.com">

 

[Faded]

sorry to hijack, but is this an exhaust bridge?

Yes.

 

[flphil]

Thanks Gomer. I did drill two holes (one spot on) and the one that is off is only slightly off. I can just see the side of the hole. Part of the problem was that the cylinder has been ported and the bridge is very narrow. The other part was that I tried a new method to keep the drill bit from moving on the piston. Basically, I put masking tape on the piston and marked the tape. I use this method when drilling into an a slick, irregular object that I cannot use a punch on (tile, glass, etc). It usually works well, however, in this case the bit did move slightly and I didn't notice it with the tape.

I will most likely see how it runs with it the way that it is. Definitely will be more careful next time.