Engine coolant stop cock Catalina 28

[jansan]

Has anyone got a cross-sectional diagram of the inlet stop cock for the engine coolant system for a Catalina 28 Mk 1 from outside hull through to filter ?

I am having problems with repetetive blockages at the stop cock (nothing at the filter ) which I am assuming after three years of trouble-free sailing/motoring indicates that there is an issue from the valve outwards.

With everything unscrewed inboard of the stop cock I haven`t been able to " feel " beyond the moving part of the valve ----- it seems to be a slot rather than a plain circular through hole.

It may well be that I shall have to dryout and tackle it from below but it would help if there was a diagram in advance.

 

[Stu Jackson]

Are you talking about your thru hull valve, Marelon? If you think there's a blockage, use a dinghy foot pump to blow it out. If you have a Universal engine, take the hose off the raw water pump and blow from there.

 

[jansan]

Are you talking about your thru hull valve, Marelon? If you think there's a blockage, use a dinghy foot pump to blow it out. If you have a Universal engine, take the hose off the raw water pump and blow from there.

Hi Stu --------clearing it hasn`t been the problem, it`s the fact that it keeps re-occuring. No problem for three years then twice in consecutive trips a complete blockage where no water is getting past the stop valve. On each ocassion I`ve unscrewed the fillter body leaving the only stop valve and there was a solid mass of seaweed/weed visible. No evidence of weed visible beyond that point at the filter.

Quickly cleared it out with a long thin rod. I am assuming that there must be a foreign body below the stop cock causing a partial obstruction giving the weed something to quite quickly build onto ------- but it`s not possible to see beyond the valve from inside the hull ( once it has been cleared ) due to the then rapid in-flow of seawater.

I think my only alternative is to get at it from under the boat.

 

[jansan]

Hi Stu --------clearing it hasn`t been the problem, it`s the fact that it keeps re-occuring. No problem for three years then twice in consecutive trips a complete blockage where no water is getting past the stop valve. On each ocassion I`ve unscrewed the fillter body leaving the only stop valve and there was a solid mass of seaweed/weed visible. No evidence of weed visible beyond that point at the filter.

Quickly cleared it out with a long thin rod. I am assuming that there must be a foreign body below the stop cock causing a partial obstruction giving the weed something to quite quickly build onto ------- but it`s not possible to see beyond the valve from inside the hull ( once it has been cleared ) due to the then rapid in-flow of seawater.

I think my only alternative is to get at it from under the boat.

Just for information-------- On inspection beyond the ball valve of the seacock ( piece of glass across the outlet of the valve body ) there was indeed an obstruction to the flow. There was either a metallic or plastic small dia rod lodged across the passageway. A coarse file eventually cleared the way just leaving the two internal installation flutes showing.

Following on from this there was a further potential problem with a sharp edge to the inside diameter of the copper pipe bridging the filter housing to the seacock. This was carefully champhered off with a grinding wheel ( courtesey of previous knowledge gas flowing combustion chambers of classic cars ! ) to allow free flow of grass/weed through to the strainer in the filter body.

Since when three hours running on the mooring and no blockages --------- contrasted with two blockages in two short trips out in the sea loch recently.

Hopefully problem solved/reduced -------- and all done without drying out.