Head backflow problems

Jul 14, 2026
4
Catalina 30 Lake Champlain
I recently purchased a 1986 Catalina 30 and I'm assuming the manual pump toilet is the original, so it's 40 years old. It worked fine for a while, but now after flushing, the waste water slowly fills the bowl back up. Just had a pump out so I know the holding tank isn"t full. Is there something I can easily replace to solve this problem? I believe it's a Jabsco, but have no documents on it.
 
Feb 26, 2004
23,354
Catalina 34 224 Maple Bay, BC, Canada
Pat, congratulations on your new boat.

Buy Peggie Hall's book: https://shop.sailboatowners.com/prod.php?53615

Join the C30 IO group:






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*All things Catalina 30 and 309! Sponsored by the International Catalina 30 Assn IC30A. FAQs, Q&A, comments, and experiences especially fixes and modifications invited. Share with over 2200 other owners. Website catalina30.com* *Please join the International Catalina 30 Association.


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This comes from this sbo thread by weekendrken:
1992 Catalina 30

Also: www.catalina30.com
 
Jul 14, 2026
4
Catalina 30 Lake Champlain
Pat, congratulations on your new boat.

Buy Peggie Hall's book: https://shop.sailboatowners.com/prod.php?53615

Join the C30 IO group:






Catalina 30 Groups
Subscribe at the web forum:

Catalina30 groups.io Group

*All things Catalina 30 and 309! Sponsored by the International Catalina 30 Assn IC30A. FAQs, Q&A, comments, and experiences especially fixes and modifications invited. Share with over 2200 other owners. Website catalina30.com* *Please join the International Catalina 30 Association.


or by sending an email to:
Catalina30+subscribe@groups.io

This comes from this sbo thread by weekendrken:
1992 Catalina 30

Also: www.catalina30.com
Thanks Stu. I just ordered Peggie's book.
 

BarryL

.
May 21, 2004
1,119
Jeanneau Sun Odyssey 409 Mt. Sinai, NY
Hello,

Changing a joker valve SHOULD be a simple job. I wrote 'simple' because you never know when a screw or bolt will be stuck, if you have good or bad access, etc. On my boat I can change a joker valve in about 5 minutes.

Be sure to pour a few gallons of fresh water into the head and pump pump pump it all into the holding tank. Then when you disconnect the output and remove the joker valve, clean water runs out instead of waste.

I will second Defender. Good prices and fast shipping.

Good luck,
Barry
 
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Likes: jssailem

dmax

.
Jul 29, 2018
1,335
Telstar 28 Buzzards Bay
You really should do a total rebuild on the head while you're in there - not that much more work, they sell kits. It will work much better.
 
Sep 24, 2018
4,531
Catalina 30 MKIII Chicago
My head smelled significantly better after I replaced the valve and cleared out the vent inside the stanchion