PV Flapper Crack

[lynngarner]

I think my 02 250 has a couple of cracks in the power valve flapper. Should I worry?? They don't go through to both sides, but since I'm new to PVs, I'd like a little counsel please. I'm doing a complete top end with replating now. Thanks.

 

[Zman]

That is a new one on me. It is steel so you could weld it. Im not sure how much they cost to replace or if they are presently available. The newer version has a contoured shape for better flow where the old design was flat.

 

[lynngarner]

I'll try to learn to post photos. I know that would help. Thanks Zman

 

[barossi73]

File size is limited for pics,search this site for file size limits.i usually photoshop etc. down to size.crop what u can first then reduce quality to suit.then just add thru attachment clip when drafting a post

 

[stian]

GG powervalves are pretty simpel, meaning that they arent high tech. My cylinder has some bad casting in the powervalve bushings, so they dont float very well. Take it up and give it a good inspection. You dont want lose steel parts in your engine.

New flapper, so ive heard, CR250 may fit with some modifications to it, if you cant find GG flapper.

 

[lynngarner]

Thanks guys. Still working on photos.

 

[Zman]

I had to do some welding on my PV flapper over the weekend. We ground too much in one spot to match the exhaust porting on my 327 big bore. I needed to fill a hole in the leading face. The flap material welds and machines very easy.

New replacements look a bit pricey. The 1995 to 1998 Honda CR250 flaps look very similar and there are at least 5 on Ebay.

 

[lynngarner]

Flapper photos

 

[Zman]

Interesting. Those look like something from the mfg process not from use. Looking from the side edges, do the cracks look like they run deep or are they just on the surface? Can you see cracks in the machined inner slot?

 

[gasgasman]

+1.

Looks like sand casting flaws.
My 2001 GG was the same way.

 

[Jacob 'Berg]

+1.

Looks like sand casting flaws.
My 2001 GG was the same way.

Yep. Those are heat tears. You can see porosity in the surface as well, both of which indicate the part was poured too hot or was not fed correctly.

 

[lynngarner]

After looking closely I agree. I cannot see any of the cracks when looking at the ends of the piece. I'm gonna use it. Thanks for the input.