Groco 6V750 Valve

[Tibsen]

Part # may not be correct as had to use cell to get the back side of valve. Pulling my boat and the valve needs servicing or replacement. Prefer to service,
Cannot find any info on Groco's site. It appears to be serviceable but do not want to be stuck on the dry dock due a crack nylon ring or something. Waiting for Groco to get back to me. Does anyone have any experience with this valve.

[HopCar]

No parts are available for that valve. If you disassemble it you’ll find the handle turns a big rubber plug with a hole in it that either aligns with the thru-hull to let water in or goes crosswise to block the water flow. The T handle is used to compress the rubber plug to lock it in place. Loosen the T handle before turning the plug.

There are two failure modes that I’m familiar with. If the valve is left closed for a long period of time, the rubber swells into the valve openings and makes it very difficult to open. If you disassemble the valve you may be able to sand down the rubber bumps that prevent it from turning.

The other failure I’ve seen is the shaft disconnects from the rubber. If that happens you’re just screwed.

Take it apart and see what condition that rubber plug is in. Then decide to replace or not.

I don’t think Groco has made those in about thirty years.

[Celestialsailor]

I will add to the above assessment that if that valve and it's 90 degree PVC elbow is below the waterline, loose the PVS elbow and buy a proper bronze one.

[deblen]

SV 750 https://www.groco.net/media/file/file/s/v/sv-series.pdf


Recommend you replace the white corrugated hose with heavy duty hose,if it is below waterline.

[Tibsen]

Thanks every one, Looks like its time to replace. Groco got back to me. Its a SV750 valve. the plug is n/a. probably time to replace. Can I assume the 2 existing flange bolts do not go through the hull but use the butt block. The new seacocks use 3 flange. Hope that i do not need to replace the thru-hull fitting and just need screw on a new valve and secure with a new butt block??