My original Jabsco on my 1999 H280 had a vertical crack on the pump assembly tube and was leaking when I pumped the toilet. I decided to replace the whole pump assembly with a new one. After installing the new assembly it leaks water. Specifically, I pull the handle up (this is to drain the toilet waste) and it draws water from the toilet, when I push the handle down it sprays water out where the flap valve is installed. I have taken it apart to verify the gaskets are installed properly. The flap is genderized so it can only go in one way. All the screws are tight. I am probably missing something obvious but I am stumped. Any input would be appreciated.
Issue with Jabsco Toiletl
- Thread starter Miken
- Start date
It is well known you can over-tighten the screws on the joker housing. You will warp the joker valve rubber flange. Start by making sure the joker is seated within the raised lip around the head outlet. Alternate tighening the screws. Tighten enough to make the screw "snubbed", not everly tight.
By the way, this is a good time to relay a previous thread that points out on the pumps with the twist-lock pump: You can turn the hand CCW past the "lock" postion and unscrew the pumps's cap. Pull the handle out and lube the piston and pump cylinder wall with (IIRC) teflon grease, white lithium I believe it is. Screw the assembly back on.
By the way, this is a good time to relay a previous thread that points out on the pumps with the twist-lock pump: You can turn the hand CCW past the "lock" postion and unscrew the pumps's cap. Pull the handle out and lube the piston and pump cylinder wall with (IIRC) teflon grease, white lithium I believe it is. Screw the assembly back on.
That's my guess: you over-tightened the screws when you put the pump on the base. That flap valve is also the gasket that seals the connection...over-tightening the screws creates a pucker in the rubber around 'em. Back 'em out just a quarter turn...flush. If the toilet still leaks, another quarter turn till it stops leaking. However, if it's been more than a day or two since your replaced the pump, the puckers may have become permanent....in which case a new flap valve will be needed.
The same thing can happen if the screws that secure the discharge fitting to the pump are overtightened 'cuz the flange on the joker valve is the gasket that seals that connection. Same cure applies...back the screws out till it stops leaking.
So when installing a pump or replacing a joker valve, start with screws that are just barely snug. If the connection leaks, just a quarter turn tighter till it stops leaking.
--Peggie
Hunter gaskets for all!
Gaskets for ports, hatches, latches, speaker pods, refrigerators, freezers, and everything that leaks.
See the product
I know you've already paid attention to this but, ensure that the screws are evenly tightened at the same time.
I've never heard the wet/dry lever called a "flapper" valve. There is a flapper/"flap" valve though...it's in the very bottom of the pump (part # 16 in the exploded drawing). The joker valve isn't even IN the pump, it's in the discharge fitting that attaches to the outside of pump body at the bottom of it (see part #33). The "lock" is a plug assembly (parts 7,8,9) Jabsco Manual Twist & Lock owners manual
--Peggie
--Peggie
Picky, Picky. The joker " IS AT" THE BOTTOM OF THE PUMP, as said. Without a discharge it's not much of a pump, is it.
Holy cow, tone it down, man! That's no way to speak to a lady, especially one who has distinguished herself in this field, and has contributed so much to this forum and the boating community.
Part number 21 [called top VALVE Gasket] in the Jabsco Parts manual referenced above.
Thus the term "Flapper Valve" gasket that is operationally a check valve for the piston pump action.
[Note: The reason the "Twist Lock" prevents back flow of sea water if the Flapper Valve is positioned right too]
Here is my trouble shooting reasoning from my post #4 above...
1) I wondered why the vertical crack? old age? over use? or OVER PRESSURED?
Note: Typical over pressure failure of ridged plastic pipe is splitting along the axis of pipe wall.
Well that eliminated the old age or over use thought in 1).
2) Why would a new pump assembly leak at the Flapper Valve gasket on a new pump?
The common failure in both the OP comments is...
He pressed down on the plunger against a...
PLUGGED discharged line.... [or very restricted]
Jim...
PS: As always my advice is worth what was paid for it....
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Very strange response. Apparently this guy cannot read the exploded diagram Peggie posted, and/or has never taken one of these Jabsco units apart, or has ever replaced a Joker. The OP needs to confirm that his discharge lines are not clogged, the Y-valve, if there is one, is switched correctly; and if to over the side, that the thru hull is open. Not likely, however, something new like that would appear just from changing the assembly.
Sorry for the confusion about the “flapper valve”. It is part # 21 called “top valve gasket”. I will check screws as recommended and make sure the holding tank is not plugged even though there are never any solids that go thru the system. It’s an interesting comment that my have caused the initial issue. I do have problems aligning the new pump assembly with the discharge elbow going to the holding tank hose because the hose is not very flexible forcing me to apply pressure to align it properly. Thanks for all the responses and I will post the results. In retrospect I should have spent the extra $60 and purchased the entire head!!
That gasket has been a problem for me as well in previous rebuilds. It’s hard to align exactly as needed. Yes, the screws have to be properly tightened, etc. Keep working with it, and you’ll get it right, IMO. I doubt the gasket is warped to an unserviceable condition.
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FWIW I usually repair a Jabsco by gently placing it in the nearest dumpster.
That's very helpful. What do you have on your luxury cruiser?
My current boat, a Tartan 3800, came with a Jabsco. I believe it's the original equipment. It works flawlessly. I carry a complete, spare pump assembly that I got last year for $80 via Amazon Prime, in case I have an issue during a cruise and want a quick solution. It's hard to beat that kind of economy, or ease of repair.
When it comes to fixing the head, they’re all the same PIA. My old Wilcox-Crittenden was no better, etc. Things just wear out.
The Wilcox-Crittenden Head Mate on my Catalina 36 worked perfectly for the 17 years I had that boat. I inherited a rebuild kit from the previous owner. Never used it, passed it on to the new owner. I guess I must just be lucky, eh?
BTW, many denigrate W-C, maybe because the Head Mate was so low priced and popular, but bear in mind they also made the Rolls Royce of marine heads, the Skipper. Hinckley used to gold-plate the external metal parts on those. They were fitted to the USNA sailboats. Used ones go for more than many good, new heads.
BTW, many denigrate W-C, maybe because the Head Mate was so low priced and popular, but bear in mind they also made the Rolls Royce of marine heads, the Skipper. Hinckley used to gold-plate the external metal parts on those. They were fitted to the USNA sailboats. Used ones go for more than many good, new heads.