Using a diesel rated outboard bulb to prime a diesel & diesel bug

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Polarsailor

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Hi All

Quick query. I have a diesel bug issue again, after having it 4 years ago. Luckily only 40litres of diesel so will get rid of it and scrub the tank etc I also plan on using Soltron going forward. The issue I think was the boat was laid up for 18 months when I was abroad working, tank filled etc and with another bug treatment added but still not ideal. Any other suggestions for things I should do welcome!

I was also thinking of adding a outboard style fuel bulb between the primary filter and engine (Yanmar 2GM20). The manual lift pump on the engine is rubbish and I usually have to crank the engine to bleed new filters. Has anyone added a priming bulb in this position and found it useful? Can anyone see an issues as long as all is airtight and the bulb is aligned in the correct direction.

Cheers Keiron
 
Polarsailor said:
Hi All

Quick query. I have a diesel bug issue again, after having it 4 years ago. Luckily only 40litres of diesel so will get rid of it and scrub the tank etc I also plan on using Soltron going forward. The issue I think was the boat was laid up for 18 months when I was abroad working, tank filled etc and with another bug treatment added but still not ideal. Any other suggestions for things I should do welcome!

I was also thinking of adding a outboard style fuel bulb between the primary filter and engine (Yanmar 2GM20). The manual lift pump on the engine is rubbish and I usually have to crank the engine to bleed new filters. Has anyone added a priming bulb in this position and found it useful? Can anyone see an issues as long as all is airtight and the bulb is aligned in the correct direction.

Cheers Keiron
Click to expand...

My diesel car has such a bulb for priming the filter when its changed........ no problems with it in 20 years.

Fit it "out" end uppermost so that air cannot collect in it. The valves work better like this too.
BUT
Your lift pump is presumably a camshaft operated diaphragm pump with a manual priming lever, The lever won't be effective if the engine stops with the pump operating arm on the toe of the cam. If having difficulty with manual priming try turning the engine though a complete turn of the crankshaft to bring the heel of the cam round to the pump.
 
Last edited:
Polarsailor said:
Hi All

Quick query. I have a diesel bug issue again, after having it 4 years ago. Luckily only 40litres of diesel so will get rid of it and scrub the tank etc I also plan on using Soltron going forward. The issue I think was the boat was laid up for 18 months when I was abroad working, tank filled etc and with another bug treatment added but still not ideal. Any other suggestions for things I should do welcome!

I was also thinking of adding a outboard style fuel bulb between the primary filter and engine (Yanmar 2GM20). The manual lift pump on the engine is rubbish and I usually have to crank the engine to bleed new filters. Has anyone added a priming bulb in this position and found it useful? Can anyone see an issues as long as all is airtight and the bulb is aligned in the correct direction.

Cheers Keiron
Click to expand...

While Soltron is a good anti-coorsion additive, it is not a biocide, and given this is your second go, your need to get smart.

Soltron (StarTron in the US) combined with Biobor JF tested VERY well in Practical Sailor Magazine and would prevent recurrence. There are certainly other combination, but make certain you actually know what each additive does based upon testing. You should be able to prevent this.

You may also have a water leak; bugs require water. Another contributor--minor in most cases--is water from the air; a silica gel vent filter is the charm for that.
 
Yes , I fitted the primer bulb to 2gm works great I have a deep keel tank and previously had a bug problem tried soltro n didn't work for me so went to marine 16 result!

John
 
I've had the bulb pumps on two boats now, and wouldn't be without one.

Petrol is more aggressive than diesel, so I would expect any of them to be fine. Although mine did say "diesel" on the packet, just to be sure.

An unexpected benefit was that when we got a blockage in the tank pickup tube, its location was apparent because the bulb was sucked flat. A blocked filter wouldn't have caused that, so it was a useful diagnostic to distinguish between the two (I have a suction gauge between primary filter and engine, which showed that a blockage somewhere on the suction side was the problem, and not a blocked secondary filter or some non-fuel-related problem).

Pete
 
If you fit a priming bulb you ideally want it between tank and the primary filter. That way it will bleed out the primary filter head chamber. ie - it will pressurise the primary filter for bleeding - and the rest of the line too - right up the the injector pump.

ASAP do bolt on ones - either IN or OUT - that fit to the 1/2 unf filter head banjos ( or 14mm metric ) Quite cheap too - had one for years.
 
Tam Lin said:
My engineer fitted one last year when I had the new engine installed. Seemed like a good idea and helped get the diesel through first time but too soon to say if there are any long term problems.
Click to expand...

Apologies for picking an earlier reply.

To effectively "prime" the main injection pump, has anybody considered (fitted?) an non return valve on the discharge side of the engine mechanical fuel pump? That would seem to answer some of the problems seen by several people?
Curious, since it ought to reduce cranking before the engine gets going properly!
 
prv said:
I've had the bulb pumps on two boats now, and wouldn't be without one.

Petrol is more aggressive than diesel, so I would expect any of them to be fine. Although mine did say "diesel" on the packet, just to be sure.

An unexpected benefit was that when we got a blockage in the tank pickup tube, its location was apparent because the bulb was sucked flat. A blocked filter wouldn't have caused that, so it was a useful diagnostic to distinguish between the two (I have a suction gauge between primary filter and engine, which showed that a blockage somewhere on the suction side was the problem, and notes a blocked secondary filter or some non-fuel-related problem).

Pete
Click to expand...
I had exactly the same blockage problem and also found it by the fact that the priming bulb was sucked flat.
 
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