Cracked Mount on Toilet Pump Assembly

ChrisCalabretta · April 28, 2025, 05:59:30 AM

We are commissioning our newly purchased 1987 C34 for the first time for the upcoming season. We were told that the Groco Model HF Series Toilet was relatively new, but we decided to install the regular HF rebuild kit so that we would have a good maintenance baseline. Unfortunately, it appears that the PO didn't get the message about not overtightening the mount screws and there is a crack in one of the mounting holes. The crack is at one of the rear mounting holes at the bottom of the pump assembly where it attaches to the base of the toilet (see photos). It goes about 1/2 way through the base on the inside of the mount hole and about 1/3 of the way through the base on the outside of the mount hole. We are trying to decide if we should just add a washer to better distribute the forces and keep an eye on it, or to bite the bullet and spend the $310 for a whole new pump assembly. I was wondering if anyone has had any experience with a similar crack and if it has lead to any issues? We are hoping to avoid an overzealous pumper or poorly timed wave leading to the mount failing and causing a mess. On the other hand, it is possible that this could be common and not a major issue?? We are trying to decide how high up on the "to do" list this should be. Thank you!

scgunner · April 28, 2025, 06:35:34 AM

Chris,

It looks like a common fatigue crack, they do wear out. I've have my boat since '88 and in that time I've repaired, rebuilt, and replaced my pump. If it's going to keep you up at nights then replace it otherwise I'd repair it with a washer and see how it holds up, you always have the option to replace it down the road. If you just got the boat I'm sure there are other places where that $300 will come in handy.

Kyle Ewing · April 28, 2025, 12:13:43 PM

I second the washer. If concerned, use a larger washer or fashion a backing plate so it has more surface area to hold the toilet down.

ChrisCalabretta · April 28, 2025, 04:59:44 PM

Kevin and Kyle- Thank you for the replies. I am leaning towards the larger washer option and keeping an eye on it this season and will likely plan on a replacement pump assembly next year for piece of mind. Thanks!

scgunner · April 29, 2025, 06:13:12 AM

Chris,

BTW, congrats on your new to you C34, they're really nice boats.

Noah · April 29, 2025, 10:21:53 AM

Perhaps in the meantime, try injecting some epoxy (for plastic) into the crack?

Stu Jackson · April 29, 2025, 01:41:39 PM

Quote from: ChrisCalabretta on April 28, 2025, 05:59:30 AM>>>>>>>>>>>>>>>>>>>>>>>>>>

>>>>>>>>>>>>>>>>>>>>>>>>>>

and spend the $310 for a whole new pump assembly.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I agree on the washer idea, although for that price you should consider a Raritan PHII (they have a new name for it). The 101 Topics has links to PHII installs.

ChrisCalabretta · April 29, 2025, 06:07:48 PM

Quote from: scgunner on April 29, 2025, 06:13:12 AMChris,

BTW, congrats on your new to you C34, they're really nice boats.

Thank you! We are really looking forward to the upcoming season!

ChrisCalabretta · April 29, 2025, 06:16:16 PM

Quote from: Noah on April 29, 2025, 10:21:53 AMPerhaps in the meantime, try injecting some epoxy (for plastic) into the crack?

I hadn't thought of this, but agree that it may be worth trying for added piece of mind. The question will be whether there is enough separation in the crack for the epoxy to penetrate, which I will check before placing a larger washer.