Yanmar seacock closer-helper

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Slycat

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Hi, I've a Yanmar SD20 and Yanmar engine and the water inlet valve is a cylinder around 1/2" diameter.

At the end of the cylinder is a slot. Sometimes its possible to turn this valve by hand but it's very difficult. As access is a bit fiddly its not easy to get a large slotted screwdriver onto the valve!

Is there a tool or cap that would fit over the end of the cylinder to make turning easier?

Thanks!
 
The valve is called a Kingston valve, on my Yanmar there is a t-piece bar at the end of the shaft to turn it and although its at the far side of the gear leg its relatively easy to turn it provided the shaft is kept well greased. Maybe there is a hole in the shaft on yours you can put a piece of rod through?
 
Slycat said:
Hi, I've a Yanmar SD20 and Yanmar engine and the water inlet valve is a cylinder around 1/2" diameter.

At the end of the cylinder is a slot. Sometimes its possible to turn this valve by hand but it's very difficult. As access is a bit fiddly its not easy to get a large slotted screwdriver onto the valve!

Is there a tool or cap that would fit over the end of the cylinder to make turning easier?
Click to expand...

More recent versions have a different design of valve which has a T-bar handle to turn. You could easily replace the valve next time the boat's lifted.
 
I think the metal spring swings over and clips into place once the valve is fully open. However I replaced mine some years ago with a DZR ball valve - much easier to operate, and you can set it so the handle is easy to get to.
 
Slipperman said:
I think the metal spring swings over and clips into place once the valve is fully open. However I replaced mine some years ago with a DZR ball valve - much easier to operate, and you can set it so the handle is easy to get to.
Click to expand...

I took the daft clips off mine Yanmars as the thing just seemed to get in the way when I tried to operate the gate valve. It's obvious whether the valve is open or not by the length of shaft showing. However, if I was ever in any doubt, I would always check it by turning it. A mistake is potentially too expensive to take the risk.

Richard
 
The spring on mine popped off the first time I used it and I couldn't fit it back on.
I guess its to stop the valve closing with vibration. I now have a piece of wood with a V cut in it that slips over the valve shaft to do the same job
 
BlueChip said:
The spring on mine popped off the first time I used it and I couldn't fit it back on.
I guess its to stop the valve closing with vibration. I now have a piece of wood with a V cut in it that slips over the valve shaft to do the same job
Click to expand...

I just don't think it's possible for a gate valve to close due to vibration. A ball valve with a heavy handle raised to open maybe, but a gate valve is intrinsically balanced and, if the flow is present as it closes, the water pressure as it closes is going to be trying to force it open again. And if the flow is not present, where is the vibration coming from?

Richard
 
RichardS said:
I just don't think it's possible for a gate valve to close due to vibration. A ball valve with a heavy handle raised to open maybe, but a gate valve is intrinsically balanced and, if the flow is present as it closes, the water pressure as it closes is going to be trying to force it open again. And if the flow is not present, where is the vibration coming from?
Click to expand...

There's no water pressure, surely? The water is being sucked through the valve by the raw water pump.
 
pvb said:
There's no water pressure, surely? The water is being sucked through the valve by the raw water pump.
Click to expand...

That's a good point! Pressure is clearly wrong.

Perhaps "flow" is the right word ...... I don't think a gate valve, particularly a horizonally mounted, one could ever vibrate shut but I'm thinking than the water flowing through the valve would also tend to hold it open rather than facilitates its closing but that might be a thought too far.

Either way, vibrating shut is the exact opposite to the problem produced by these silly valves .... it's closing at all that this the usual issue.

Richard
 
On my SD50s I always unscrew the T handle fully and then turn it back in maybe 1/8th of a turn before putting the spring in position. It seems to help avoid them seizing into the fully open position.
 
runningman said:
On my SD50s I always unscrew the T handle fully and then turn it back in maybe 1/8th of a turn before putting the spring in position. It seems to help avoid them seizing into the fully open position.
Click to expand...

I don't understand how it could do that? What would be different if you took the spring off? :confused:

Richard

Ah.....having now re-read this thread I can see that the "avoiding seizing" comment was related to the "1/8th turn" rather than the "spring".
 
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Have just replaced the valve on a SD20 Saildrive with a ball valve. There are posts on other forums on it. It's simple to do and it can be done withe the boat in the water if you don't mind mopping up a bit afterwards.
However, what I did find when I got the old original gate valve into the workshop. It needed a vice and a big spanner to work the valve closed. Eventually did it.
For reference the valve needed 10 turns fully open to fully closed. I suspect that if these valves don't have 10 turns they may require investigation.

Mine had 5 turns and locked solid that left me thinking it was shut when it was actually open!

Personally I would give these valves a good check as mine was moving freely but not closing properly. There are quite a few posts on the web about this problem.
 
blxm said:
Have just replaced the valve on a SD20 Saildrive with a ball valve. There are posts on other forums on it. It's simple to do and it can be done withe the boat in the water if you don't mind mopping up a bit afterwards.
However, what I did find when I got the old original gate valve into the workshop. It needed a vice and a big spanner to work the valve closed. Eventually did it.
For reference the valve needed 10 turns fully open to fully closed. I suspect that if these valves don't have 10 turns they may require investigation.

Mine had 5 turns and locked solid that left me thinking it was shut when it was actually open!

Personally I would give these valves a good check as mine was moving freely but not closing properly. There are quite a few posts on the web about this problem.
Click to expand...

My experience exactly. For the first season I had my boat I thought that I was closing the SD20 valves when I left the boat. It was only when I read the "10 full rotations" on a forum that I realised I might be mistaken so I started an engine with the valve closed ...... and it wasn't.

Freeing off the 2 valves to achieve 10 turns took me all day. :(

Richard
 
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