Henderson MkV (5) servicing.

[Refueler]

I have two Mk V's on board .... one does the engine bay - other does the shaft area ...

The Engine bay pump even after 30 odd years still pumps like a good-un ...

The shaft area one is ????

So decided to remove and have a look ...

Taking apart - I find 4 M5 screws ... 2 self tappers .... 3 washers and 3 nuts - that fit the M5's .... all sitting in the pump chamber. Again this pump is over 30yrs old and all good ... both valves good ... diaphragm good ...

What I found was something that is quite common ... a short piece of pipe to fit pump - then a slightly smaller diameter pipe to suction pushed into that short pipe and tape-sealed.

Clean it all up ... (of course emptied the screws etc !) ... retaped / joined pipework .....

NOW it pumps !! But obviously the suction end of pipe has something ... so will need lift cockpit sole later and have a gander at that ...

Reckon 30 odd yrs is not bad ... diaphragm and valves are still supple ...

 

[Buck Turgidson]

I have two Mk V's on board .... one does the engine bay - other does the shaft area ...

The Engine bay pump even after 30 odd years still pumps like a good-un ...

The shaft area one is ????

So decided to remove and have a look ...

Taking apart - I find 4 M5 screws ... 2 self tappers .... 3 washers and 3 nuts - that fit the M5's .... all sitting in the pump chamber. Again this pump is over 30yrs old and all good ... both valves good ... diaphragm good ...

What I found was something that is quite common ... a short piece of pipe to fit pump - then a slightly smaller diameter pipe to suction pushed into that short pipe and tape-sealed.

Clean it all up ... (of course emptied the screws etc !) ... retaped / joined pipework .....

NOW it pumps !! But obviously the suction end of pipe has something ... so will need lift cockpit sole later and have a gander at that ...

Reckon 30 odd yrs is not bad ... diaphragm and valves are still supple ...

My MK3 is still going strong.

 

[geem]

I have two Mk V's on board .... one does the engine bay - other does the shaft area ...

The Engine bay pump even after 30 odd years still pumps like a good-un ...

The shaft area one is ????

So decided to remove and have a look ...

Taking apart - I find 4 M5 screws ... 2 self tappers .... 3 washers and 3 nuts - that fit the M5's .... all sitting in the pump chamber. Again this pump is over 30yrs old and all good ... both valves good ... diaphragm good ...

What I found was something that is quite common ... a short piece of pipe to fit pump - then a slightly smaller diameter pipe to suction pushed into that short pipe and tape-sealed.

Clean it all up ... (of course emptied the screws etc !) ... retaped / joined pipework .....

NOW it pumps !! But obviously the suction end of pipe has something ... so will need lift cockpit sole later and have a gander at that ...

Reckon 30 odd yrs is not bad ... diaphragm and valves are still supple ...

It why Blakes Lavacs are such reliable toilets.,they use a white cased version of a Henderson mk5

 

[noelex]

We have three. They have a reputation for reliability. Keeping them the same reduces the spare parts needed.

 

[capnsensible]

It why Blakes Lavacs are such reliable toilets.,they use a white cased version of a Henderson mk5

With our lavac, I had one pump spare ready to go and a servicing kit. Quick swap, 15 minutes to swap pumps. Loadsa time to refit broken one.

Few problems during 22 years liveaboard. Gets my vote!

 

[Refueler]

I have always thought that if my Baby Royal ever fails on the empty pump - I would modify to use a Mk V ..

I have to say - I do not like Lavac bogs .... my Royal just keeps on working ..... year in year out ... I have had the boat over 24yrs and I have never serviced it ... I just throw a bit of Cooking Oil through it occasionally to lub the seals / pump ... keep the greasers topped up ... Antifreeze through it for winter.,

 

[geem]

I have always thought that if my Baby Royal ever fails on the empty pump - I would modify to use a Mk V ..

I have to say - I do not like Lavac bogs .... my Royal just keeps on working ..... year in year out ... I have had the boat over 24yrs and I have never serviced it ... I just throw a bit of Cooking Oil through it occasionally to lub the seals / pump ... keep the greasers topped up ... Antifreeze through it for winter.,

You love the Henderson Mk5 but you don't like Lavacs? All the moving parts of Lavac are in the MK5 making th Lavac just a bog. Something doesn't make sense there.
As full time liveaboards we worked out that our bog does 20 years use in the equivalent of a 5 years of normal use for a weekend sailor in the UK.
Reliability is everything to us

 

[Refueler]

You love the Henderson Mk5 but you don't like Lavacs? All the moving parts of Lavac are in the MK5 making th Lavac just a bog. Something doesn't make sense there.
As full time liveaboards we worked out that our bog does 20 years use in the equivalent of a 5 years of normal use for a weekend sailor in the UK.
Reliability is everything to us

Its the vacuum side that I am not a fan of ...

I have been on a number of boats where the seal when seat closed has no been so good. I have nothing against its ability to pump out the efluent ... its the drawing in of water by that vacuum that I have seen fail.

My Royal has a pump to fill the bog ... and a pump to empty it ... no need for vacuum or anything else.

You get used to what you have ... I like my Royal ...

Seen the price of it ?? Its near 50% of the boats value !!

 

[geem]

Its the vacuum side that I am not a fan of ...

I have been on a number of boats where the seal when seat closed has no been so good. I have nothing against its ability to pump out the efluent ... its the drawing in of water by that vacuum that I have seen fail.

My Royal has a pump to fill the bog ... and a pump to empty it ... no need for vacuum or anything else.

You get used to what you have ... I like my Royal ...

What? The vacuum is a function of the suction of thr Henderson pump. The seal is is just a seal. It's either in good condition or it isn't. My pal had the same seal on his Lavac in the Tropics for 15 years as a liveaboard full-time. He replaced it and 10 years later its still going strong.

 

[Refueler]

What? The vacuum is a function of the suction of thr Henderson pump. The seal is is just a seal. It's either in good condition or it isn't. My pal had the same seal on his Lavac in the Tropics for 15 years as a liveaboard full-time. He replaced it and 10 years later its still going strong.

I applaud your support of the Lavac ... but think you ought to think a bit ..

The Lavac relies on the Mk V creating a vacuum in the bowl once the lid is closed - that's how it draws in the replacement water. If the lid doesn't seal - then all you do is pump out ... no water comes in.

Seen it and got the T Shirt ...

I have no intention to replace my Blakes ... with its separate pumps.

 

[geem]

I applaud your support of the Lavac ... but think you ought to think a bit ..

The Lavac relies on the Mk V creating a vacuum in the bowl once the lid is closed - that's how it draws in the replacement water. If the lid doesn't seal - then all you do is pump out ... no water comes in.

Seen it and got the T Shirt ...

I have no intention to replace my Blakes ... with its separate pumps.

I give in. Its like pulling teeth. Sit on yer bog an enjoy yourself

 

[rogerthebodger]

I have 3 Henderson Mk V and a Chinese look a like

I have a Lavac and the only issues I had had was the black seat seal was not sealing correctly thus loss of vacuum/ This was fiixed by replacing it with a white seat seal with a longer seal tong The other issue I had with a Mk V was the plastic cntre nut broke and I could not determin the thread so made a replament in stainless steel. I found out later the thread is 3/4" Whitworth

I did blow one of mine up by poring too much Hydrochloric acid into my Lavac and the Mk V blow the case apart amd beinh polyproplene could not glue it back together

My Lavac and Mk V must be over 40 years old as was from a previous boat built in the mid 1970's

I also have a modified Jabsco that uses an electric disphram pump to pump out and a separate water pomp for the flush

 

[Refueler]

I give in. Its like pulling teeth. Sit on yer bog an enjoy yourself

Yep - your teeth.

 

[Cotillion]

I have two Mk V's on board .... one does the engine bay - other does the shaft area ...

The Engine bay pump even after 30 odd years still pumps like a good-un ...

The shaft area one is ????

So decided to remove and have a look ...

Taking apart - I find 4 M5 screws ... 2 self tappers .... 3 washers and 3 nuts - that fit the M5's .... all sitting in the pump chamber. Again this pump is over 30yrs old and all good ... both valves good ... diaphragm good ...

What I found was something that is quite common ... a short piece of pipe to fit pump - then a slightly smaller diameter pipe to suction pushed into that short pipe and tape-sealed.

Clean it all up ... (of course emptied the screws etc !) ... retaped / joined pipework .....

NOW it pumps !! But obviously the suction end of pipe has something ... so will need lift cockpit sole later and have a gander at that ...

Reckon 30 odd yrs is not bad ... diaphragm and valves are still supple ...

My 40yo heads pump was badly scaled and not pumping as it should. So thought I give it a service. Went to my local chandlers web site to find a price for the service kit to be £45 also noticed they were selling the complete new pump for £73. No contest.

 

[penfold]

I applaud your support of the Lavac ... but think you ought to think a bit ..

The Lavac relies on the Mk V creating a vacuum in the bowl once the lid is closed - that's how it draws in the replacement water. If the lid doesn't seal - then all you do is pump out ... no water comes in.

Seen it and got the T Shirt ...

I have no intention to replace my Blakes ... with its separate pumps.

Your blakes relies on the filling pump creating a vacuum with the plunger seal; it could fail then no water comes in.

 

[Refueler]

Your blakes relies on the filling pump creating a vacuum with the plunger seal; it could fail then no water comes in.

True ... but does not require closing bog seat and relying on that.....

 

[penfold]

I thought it was only germans who liked watching jobbies get sucked around the bend.

 

[geem]

True ... but does not require closing bog seat and relying on that.....

So you think a seal is something not to be relied up on? You have got to be kidding

 

[Refueler]

So you think a seal is something not to be relied up on? You have got to be kidding

What is it with you guys ...

I post about my BILGE pumps and it turns into a Lavac debacle ...

I am not interested ... having been on a number of boats that that ******** seal failed ..

 

[geem]

What is it with you guys ...

I post about my BILGE pumps and it turns into a Lavac debacle ...

I am not interested ... having been on a number of boats that that ******** seal failed ..

Oh good grief, give us a break
I can change both of those seals in under 60 seconds. Never needed to change one in 11 years on the last boat. Friends lasted 15 years, in the Tropics.
You can buy the seals for little money. If all bogs could have parts changed in less than 60 seconds there would never be posts on this forum on bogs