Top tip for diesel bleeding

davidej

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I have a Bene with a VP2030 and a CAV type primary filter with the glass bowl water separator at the bottom. This type is rightly reviled here and was inordinately difficult to change in a confined space - I don't know how you would ever do it at sea!

The diesel tank is well below the level of the filter and the feeble lift pump would not get fuel up the pipe and into this filter. Two hours of other attempts including trying to fill it thru the bleed hole, sucking it up with a Pela pump etc proved fruitless.

Then I remembered reading about this. Fit in the pipe from the tank to the primary filter, squeeze a couple of times and - easy peasy - job done.

Keeps positive pressure though the whole system and you can then crack each joint in turn to expel the air. I would now feel confident about having to do it at sea
 
I have a Bene with a VP2030 and a CAV type primary filter with the glass bowl water separator at the bottom. This type is rightly reviled here and was inordinately difficult to change in a confined space - I don't know how you would ever do it at sea!

The diesel tank is well below the level of the filter and the feeble lift pump would not get fuel up the pipe and into this filter. Two hours of other attempts including trying to fill it thru the bleed hole, sucking it up with a Pela pump etc proved fruitless.

Then I remembered reading about this. Fit in the pipe from the tank to the primary filter, squeeze a couple of times and - easy peasy - job done.

Keeps positive pressure though the whole system and you can then crack each joint in turn to expel the air. I would now feel confident about having to do it at sea

Thats the priming bulb I've got on my Rover 45 diesel, just before the filter.
Changed it recently, cos air can get in with age - got a new one from screwfix, much better price than motorcentres £7.99 + definitely for diesel.

http://www.screwfix.com/p/diesel-fuel-pump-priming-tool/77865?_requestid=892611

From your post, initially I thought you were using the bulb to pressurise your fuel tank.
 
Odd... I have the same type of primary, but a VP D2-55, this engine has hand push priming pump near the secondary (engine) fuel filter. I have never had problems priming just using that pump.
 
i bought one (new ) from a forumite i have yet to fit it as concerned about diesel fuel eating it.

Well, the one I bought was sold for use with a petrol outboard, but also said "suitable for diesel" on the packet. I assume that applies to others. Petrol is rather more volatile and degrading to rubber than diesel is.

Pete
 
The bulb is a great idea and I fitted one a couple of months back.

To make it even easier, and a doodle while at sea, fit RACOR filters (see many previous threads)
 
The bulb is a great idea and I fitted one a couple of months back.

To make it even easier, and a doodle while at sea, fit RACOR filters (see many previous threads)

Yep, fantastic. Who ever designed the CAV system had a complex mind. RACOR, spin on, spin off. :) No washers, no fiddly bolts and dead easy to bleed.
 
To be fair, the CAV design probably pre-dates the spin-on filter! They were used on many vehicles and intended to be mounted with good access. You can get an adaptor to fit the CAV body to take spin-on filters, though - they were available from ASAP Supplies, but I believe you lose the glass bowl.

Rob.
 
renault fit a priming bulb to their diesel meganes (and probably others) you wouldn't be able to find the lift pump assuming there is one..peugeot put an electric one in the tank...
Maybe all these good things could be got at a scrappy for a few quid.
 
Some of these bulbs have a tiny filter built into the intake end which can easily be blocked over less than a seasons use. This happened on a friends boat, and it took us a while to figure out where the problem was! Needless to say on a very lumpy day in the Irish Sea.
 
>CAV type primary filter

We used Racor Spin on filters because they have an inbuilt pump that will easily pull fuel from a tank well below the filter. Like mobos we had two in parallel so if one blocked just switch to the other. Obviously you have to bleed both of them after fitting them.
 
Fuel pump

I've been thinking about fitting a bulb pump to make bleeding the system easier, but am wondering if it could be fitted before the lift pump.
I have a Nanni engine, with a water separator, which fills without a problem as it's below the fuel tank, then the lift pump and then the fine filter on the engine block. There is plenty of room to fit the bulb before the lift pump, but a very short length of fuel pipe between the lift pump and the filter.
My question is, would the bulb push the fuel through the lift pump? Would pumping the lever on the lift pump at the same time as using the bulb help?
My feeling is that the bulb wouldn't push fuel through the lift pump, but I'm open to any other views/experience.
 
Fitted one a couple of years back, on forum recommendation. Impressively quick

IIRC the bulb hardens as a sign of ageing.... (?)

Bit sad this but I do carry an unused and identical primary and secondary fuel filter assembly. These things are cheap when you are are able to source them opportunistically and not under duress. Well, when I say cheap:D
 
I must be lucky. On the Rustler 44 I only need to pump the little pump on the engine fuel pump twenty times or so and that bleeds the whole system. And that's after a change of primary and secondary filters.

Need to do it twice though, as we have switchable Racors and they need to be bled separately.
 
I've been thinking about fitting a bulb pump to make bleeding the system easier, but am wondering if it could be fitted before the lift pump.
I have a Nanni engine, with a water separator, which fills without a problem as it's below the fuel tank, then the lift pump and then the fine filter on the engine block. There is plenty of room to fit the bulb before the lift pump, but a very short length of fuel pipe between the lift pump and the filter.
My question is, would the bulb push the fuel through the lift pump? Would pumping the lever on the lift pump at the same time as using the bulb help?
My feeling is that the bulb wouldn't push fuel through the lift pump, but I'm open to any other views/experience.

I can't claim any great expertise but I would fit it before the primary filter. it would pump fuel through both filters to the lift pump.

I imagine the lift pump does have valves that would allow pressurised fuel thru. But I have found that once the lift pump is filled, cranking the engine soon gets it right through to the injectors.
 
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