O-Ring seating problems

[Zanshin]

I'm fixing my guest head pump assembly and have replaced the broken parts. But I'm having great problems in putting the pump assembly back into place. It has a groove for an O-Ring and I cannot get the new O-ring to seat, and the old one won't stay in place either. I've tried heavy grease and Vaseline to get this to stay in place, to no avail!
Part of the problem is that the groove is cut straight as opposed to convex - which would hold it in place. And I need to put the pump upside-down to get it into place for mounting, plus the location behind the head is difficult to access.

I'm debating getting an adhesive and using that to keep the ring in the groove - but which one?

I'd welcome any suggestions.

[Charlie-Bravo]

Petroleum based grease … vasoline may attack the o ring, ……… but not for a while.
Getting a different size o ring , given your location, might be a challenge,  so removing that option, try putting the o ring not in the groove, but on the mating part, perhaps with a glob of something slippery, sounds ridiculous but can work, then push the fitting with the groove onto it, and with much wriggling you may find it pops into its groove as it has nowhere else to go, slide in the screws and the jobs a goodun.
Failing that clean everything of slippery stuff, and try superglue to keep it in place, it will glue the o ring ….. but may not adhere to the part it goes into …….. but you have to try something ehh?

try a beer or rum before assembly, it gives a different level of concentration!

CB

[Zanshin]

I ended up using some sticky tape to tape the O-ring in place and then assembled the part, hand-tightening the 4 screws. Then I eased the 2 pieces of tape out between the parts and it was sufficiently tight to keep the O-ring in place while letting the scotch tape slide out. 3 hours wasted just to mate 2 simple parts together. If only Jabsco had correctly machine the groove in the first place.

[Charlie-Bravo]

Ooooo a new technique to add to the arsenal , never even thought of tape ! ( perhaps the exotic rum inspired it )
Jabsco woes here as well , but just the joke of the joker valve, so not a huge challenge ahead. I am looking to find an alternative anti back flow item that might fit, I seem to go through 2 jokes a year.

Happy flushing
CB

[loredo]

To Zanshin,

the only way to get the job (take pump off and back on) done in a reasonable time is to disassemble the whole toilet.

First time I did it like you.  I think I shouted more dirty words that time than the rest of my life!

To make all this easy and uneventful, take off the bowl from it's base. The calmp that holds the hose at the top of the bowl and four 10mm nuts at the base. MAYBE a 10 minute job. Then take of the complete base with the pump still attached to it. That's another three 13 mm screws and 5 minutes later you have the whole thing in your hands. 

Now, getting the darn O-ring back in place is a piece of cake. 

DO NOT overtighten the four tiny brass screws that hold the pump onto the plastic base! You might get a hair crack in the plastic base which will result in a continous very light drip unpossible to locate.  Don't ask how I know...

To Charlie bravo,

you might try to use a non return valve in the discharge hose instead of the flimpsy joker valve.

Whale makes a rather inexpensive 1.5 inch one.

Loredo

[Charlie-Bravo]

Thank you Loredo, I’ll take a look at it and measure up .
CB

[Don Reaves]

May 16, 2022 10:22:51 GMT Charlie-Bravo said:

Thank you Loredo, I’ll take a look at it and measure up .
CB

CB -- If you do this replacement, please take pictures and post them. I'm also having to replace the joker valve more than once per year, though I have it down to a science so it isn't a messy job.

Don

[loredo]

Check valve LV 1215 here :

www.whalepumps.com/marine/siteFiles/resources/docs/product-accessories-spares/Accessories/PipeworkConnections.pdf

Loredo

[Charlie-Bravo]

The whale non return and similar from force 4 have, guess what ….. a joker valve inside them, suppose 2. might work better than one, …..but am I just going to be replacing 2 instead of one once or twice a year?

I have also spotted a Trudesign one way valve but looking at the cutaway view some ‘things’ might obstruct it, and Trudesign state that it is not suitable for black water use.

When I took out the last one I left it (cleaned first) with bull dog clips on it , hoping it would re shape its self back to how it was when new, and intended at the time to bake it in the oven when Mrs CB wasn’t watching …… but didn’t get around to it. 

Off to the shed … I’ll have a go with a heat gun.
CB

[Charlie-Bravo]

A failure, heat gun doesn’t mend old joker valves.
CB