| Author |
Message |
    
Clarrie Beckingham
Member
Username: beckinc
Post Number: 8
Registered: 10-2008
| | Posted on Sunday, February 20, 2011 - 12:53 am: | 
|
Hi
Engine B&C 3.5HP stopping recently. I realise there could be a multitude of reasons. Suspect fuel flow/stoppage. Does the fuel tank cap need a breather hole and what size? .
Many thanks, '
Clarre Beckingham |
Bruce Hall
Senior Member
Username: bruce
Post Number: 255
Registered: 07-2002
| | Posted on Sunday, February 20, 2011 - 09:42 pm: |
|
Fuel tanks are best vented to the exterior of the hull to eliminate vapor or liquid fuel expansion reaching the bilge. A fine mesh screen in the through hull fitting lessons the possibility of insects or foreign matter plugging the vent |
Bruce Findlay
Senior Member
Username: bruce_findlay
Post Number: 55
Registered: 03-2006
| | Posted on Sunday, February 20, 2011 - 09:52 pm: |
|
Hi Clarrie, my old putt putt has the fuel tank mounted below the forward deck with its opening protruding through the deck. The filler tube has a brass cover secured by a chain. The cover has a very tiny hole, maybe as small as 1/32", drilled in its top to act as a breather. The fuel lines in my boat are prone to air locks and I have to blow the fuel through the line until I see the air bubbles come out of the carby float hole. Yours might be the same. Cheers, Bruce. |
Laurie Derwent
Senior Member
Username: laurie_d
Post Number: 87
Registered: 10-2009
| | Posted on Sunday, February 20, 2011 - 10:28 pm: |
|
I concur with the above. For a small motor that's only using a litre or three an hour that very small hole in the cap or a slightly loose fitting cap that allows breathing is practical and adequate. The breather line is OK but it has to be positioned to avoid fuel locks or taking in water especially when under way. In small boats that can be difficult. I once took delivery of a 21' boat with inbuilt tanks filled from the rear end. The first problem was that the builder did not include any breather in the top of the tank. The second was that when the breathers were fitted they were at the rear end of the tank. The boat (not a trailer boat) sat with the tanks tilted down at the rear so it became impossible to fill the tanks as there was no way for the air trapped in the front/top to escape. 'Twasn't me who ordered the boat and any implied warranty that the tank (and some other intetresting features) would be set up under CDF (common sense) principles was discussed at length but with not much success. |
Clarrie Beckingham
Member
Username: beckinc
Post Number: 9
Registered: 10-2008
| | Posted on Sunday, May 01, 2011 - 01:11 am: |
|
Many thanks Fellows,
My apologies for not replying sooner, I went into hospital for surgery. I will drill a tiny hole in like Bruce suggests. I also had the fuel line running from tank down then up before going down to carby. This I corrected to run downwards for all of the line and this has corrected the problem. Once ageain aplologies for delay in replying, I have Parkinsons and went into hospital for DBS Surgery. It has turned my life arond for the better,
THank you, Clarrie Beckingham |
