Mechanical Vs Electric lift pump

[ghostlymoron]

Or fit an outboard type bulb for priming?

 

[lw395]

Here's a pic of my water pump


Access is from a small hatch in the cockpit floor or by crawling through the heads and reaching round the back of the engine. The linkage to the gearbox prevents me from getting a normal screwdriver on the coverplate screws but a 'stubby' will get it but you can't put much force on it. The shape of the casing makes it impossible to get a socket on the bolts holding it to the engine and I can only get an open ended spanner on them at an angle. It seems impossible to apply enough force to shift the as I am hampered by the gearbox linkage and the throttle cable. Grrrrrrrrrrr

I'd change those for allens.
And get a fair bag of spares....

Or studs and wing nuts.

 

[ghostlymoron]

Something has to be done. Will ring speedseal re thumbscrews then remove pump for overhaul. It must come off somehow!

 

[pappaecho]

My boat has twin Mermaid diesel which have done about 4000 hours. Port engine started cutting out, even when the pump was renewed. Suggestions about worn driver cam, but not worth pulling the engine to pieces. Fitted electric lift pump and never had any more problems. Added advantage, is for when bleeding the system, just switch on the ignition, to allow the pump to purge the system, just bleed the injection pump and bobs your uncle in a couple of minutes

 

[ghostlymoron]

Do you know where I can get 5/32" unf Allens?

I'd change those for allens.
And get a fair bag of spares....

Or studs and wing nuts.

 

[charles_reed]

Do you know where I can get 5/32" unf Allens?

Go to a good fixings stockist - there are a couple in Telford, just use Yellow Pages and the phone.

 

[ghostlymoron]

Thanks for that advice, Charles, good to have local advice from a fellow Shropshire. Lad.

Go to a good fixings stockist - there are a couple in Telford, just use Yellow Pages and the phone.

 

[lw395]

Of course the alternative to a lift pump that runs continuously is a 'day tank' gravity feeding the injector pump.
Very reliable, gravity.

 

[charles_reed]

Of course the alternative to a lift pump that runs continuously is a 'day tank' gravity feeding the injector pump.
Very reliable, gravity.

The cars I first drove had bulkhead mounted tanks or, on Alvi and Bentleys, a device called an Autovac which transferred fuel from a rear-mounted tank to the little tank on the bulkhead from whence it flowed to the multiple, thirsty SUs.
On the 4.5 litre blower Bentley the single SU was mounted on the inlet to the crankshaft-driven Rootes blower which nestled between the front dumb-irons. This led to a long copper pipe from bulkhead to blower which invariably suffered a fatigue failure - petrol on a hot blower used to result in some interesting fireworks.
Personally, though I've often suspected failure of a mechanical fuel pump, I've never actually experienced it, though I've has frequent failures of electric lift pumps - originally the SU but more recently the fully submerged Valeos fitted to a number of French cars.

 

[Leighb]

Our fuel tank is in the bilge, well below the engine. The lift pump on the original Volvo was obviously able to cope with the height difference, but when I re-engined with a Beta the installation instructions clearly stated that the pump could manage a maximum lift of 0.25m. The lift would need to be a metre or so, so we installed an electric pump inline and it has been fine, I suppose in the event of a total electrical failure the engine might stop, but better that than being difficult to start most of the time.