Fuel isolator.Should there be one?

[ctroutz]

Posted the other day, praps wasn't very clear. I've got a mid seventies colvic watson with a thorny croft 90. Just changed oil filter and one fuel filter. There's a square plastic? reservoir attached to fuel tank with a rusty tap on the bottom (which I assume is the water separator). I'd like to attack it but I can't find a fuel isolator. Anyone got anything similar and is there likely to be an isolator somewhere? If there isn't, Any suggestions?
The reservoir is just clipped into a rusty frame so I'd like to replace the whole thing if poss. Hope someone can help. Thanks.

 

[Caer Urfa]

Posted the other day, praps wasn't very clear. I've got a mid seventies colvic watson with a thorny croft 90. Just changed oil filter and one fuel filter. There's a square plastic? reservoir attached to fuel tank with a rusty tap on the bottom (which I assume is the water separator). I'd like to attack it but I can't find a fuel isolator. Anyone got anything similar and is there likely to be an isolator somewhere? If there isn't, Any suggestions?
The reservoir is just clipped into a rusty frame so I'd like to replace the whole thing if poss. Hope someone can help. Thanks.

Yes 'sounds like' an old water trap but any pictures? Any pipework coming off the reservoir or just a tap?

Yes you should always be able to isolate the main fuel tank, does your fuel filter have a water separator or is it a spin on type?

What sort of fitting is there from the fuel tank to this so called plastic reservoir box? if it is a hosetail fitting you can just by pass the reservoir and go straight to the fuel filter with an inline shut off tap before it using 'approved' rubber fuel pipe

Or drop me a PM

Mike

 

[sarabande]

could it be a 'day tank' ? How big is this plastic reservoir ? Does it have a feed to the fuel filter/injector pump ?

Mike knows his way round the CW fleet like no-one else.


What's the name/size of your CW. I had one for 6 years.

 

[ctroutz]

Thanks Mike, I'll get down and take a couple of pics.The reservoir is fixed towards the top of the fuel tank,I think just with a pipe in and out but they all look like copper hence the problem with shutting off the supply.The only filter is a CAV one with cartridge replaced. (We eventually sorted the oil filter change ok after it chucked half a gallon into the bilge.I've bought a spin on adaptor for that next change.)
As you'll have gathered, I'm not the 'brightest' on this but I'll get the pics,double check re your questions and come back.Many thanks for responding. Graham.

 

[ctroutz]

Hi, Thanks for replying. She's 26 with an aft cabin. Was moored at Pembroke Dock and an excellent guy, Ken Nutt, sailed it round to Newlyn for me late August last year. We brought it back from there,excellent trip, Dolphins and all sorts! Name's Gaukler...German for clown apparently....No comments invited!
As i said to Mike: The reservoir has an in and out pipes, runs to the filter. I would guess the capacity is a bit less than a litre. Thanks again, Graham.

 

[Caer Urfa]

Thanks Mike, I'll get down and take a couple of pics.The reservoir is fixed towards the top of the fuel tank,I think just with a pipe in and out but they all look like copper hence the problem with shutting off the supply.The only filter is a CAV one with cartridge replaced. (We eventually sorted the oil filter change ok after it chucked half a gallon into the bilge.I've bought a spin on adaptor for that next change.)
As you'll have gathered, I'm not the 'brightest' on this but I'll get the pics,double check re your questions and come back.Many thanks for responding. Graham.

Hi Graham

Yes I remember Gaulker a 1976 CW 25'-6" AC with a dark hull, green I think.

Is the tank SS or plastic? and what size is the copper pipework micro bore or larger?

By the way do you only have one tank? or two?

If you send your address to me by PM on here I will contact you direct, either way things can be sorted as one thing you need 100% is a good fuel sytem.

Mike

 

[ctroutz]

Hello Mike, Got interrupted when I was about to message you and was logged out. Could you let me know if you received my PM? I tried again so you may have received a duplicate.
Regards,
Graham.

 

[Jim@sea]

When I bought my Colvic Watson last year I was surprised to find that you could not turn the diesel off. There was one valve/fuel switch with 3 connections, one from each tank and one going to the filter and the lever would only go 90 degrees, if it was down it was taking diesel from the port tank, if it was sideways it was taking diesel from the starboard tank and if it was halfway it was taking diesel from both tanks, which meant there was always diesel going to the engine.
An excellent photo from "Caer Urfa" showed what he had done and I have done the same, in that at very little cost I have fitted 2 fuel valves (one from each tank) so I can take diesel from each tank independently and shut both down.
Two other things. The boat I bought was advertised as having a Thornycroft 90. By chance I found it had a bigger engine. How do you know which engine you have. I only found out when I downloaded the BMC Engine Parts Guide for a Thornycroft 90 and it looked a bit different than the engine I have. Then I downloaded the parts list for the Thornycroft 154 and it is identical to the engine which is in mine.
Also your engine appears to be short of a filter, the one with a Glass Bowl. And on my engine the diesel return went back to the filter, (so that if there was any air in the system it kept getting sent round and round. I have had it re-plumbed so that the excess diesel goes back to a tank and any air vanishes.
These Colvic Watsons can only go up in value.