Pump Lift

[Stu Jackson]

Return line valve and supply line

You guys might wanna stay in electronics!

I agree with Ron that the valve on the return line is not required and may even prove to be dangerous if installed this way. Let's say, for example, that you forget to turn the return line valve and you start your engine. Where is the fuel return gonna go? I know, I know, you'd NEVER forget... The two return lines are much simpler, and idiot proof - at least I can confirm that when singlehanding there's always one idiot on my boat!

You show the priming pump in front of the Racor from the fuel tank. Most of us with Facet electric fuel pumps, which have screens (also called filters, incorrectly) in the bottom of the body, have relocated them after the Racor. The pump screen clogging was not amusuing.

 

[Bob Poff]

Thanks Stu, I'll relocate the primer pump.
Makes sense.

Oh I'll freely admit that while I've been able to teach myself to do lots of things in my 50 years, there are some things that I'm not as good at as others. This is one of them.

I'm much more confident working on an AM directional array, my current charges shown in the attached picture, or one of a hundred other things, than doing any sort of plumbing.

But then isn't that what these forums are about?
If I knew everything, life would be boring.

 

[RichH]

You want to locate the Racors near the LOWEST part of the delivery system .... so that any water that enters the delivery line can be easily removed AT the filter. If you put the filters 'not' at the lowest section of the line, the line 'may' fill with water (not good for a typical copper fuel line as the water will become quite acidic) which will promote fungal and other bio-growth and the line will eventually foul and become blocked with the biomass. Fuel filters go at the LOWEST portion of a fuel system.

 

[Stu Jackson]

Not so fast there...

You want to locate the Racors near the LOWEST part of the delivery system .... ... Fuel filters go at the LOWEST portion of a fuel system.

I respectfully disagree, Rich. Our engine is lower than our fuel filter. The fuel tanks on MOST boats is lower than the fuel filter. On our C34s, just for example, we have a VERY unusual situation, where the fuel tank is actually HIGHER than the fuel filter and the engine. In spite of that tank location, we have fuel pumps, which we find very helpful in bleeding the system when required. Our fuel pumps operate all the time the ignition switch is on. In order of height: fuel tank, fuel filter, engine. On most other boats: fuel filter, engine, fuel tank.

So, while I understand your concern that fuel with water in it could be trapped in a line, it just doesn't fit with reality. You just can't make that happen on most boats, and most boats have them higher than the lowest point and have been working that way for years.

Look forward to your comments, thanks,

Stu

 

[RichH]

I respectfully disagree, Rich. Our engine is lower than our fuel filter. The fuel tanks on MOST boats is lower than the fuel filter. .......

So, while I understand your concern that fuel with water in it could be trapped in a line, it just doesn't fit with reality. You just can't make that happen on most boats, and most boats have them higher than the lowest point and have been working that way for years.

Look forward to your comments, thanks,

Stu

Stu - thats simply BAD design. I know, I know, .... boat builders just dont have the expertise or knowledge to instal 'decent' or proper fuel systems. They use the cheapest components possible, install compression fittings (notorious leakers), copper tube (incompatible with long term diesel contact), obsolete rubber hosing .... and leave it up to the owner to correct - later. "Reality" is that there 'are' some boat fuel systems that are adequate ... just not found on most 'production' boats. The filters are the most common point for an owner to 'open' the system; when at the lowest portion of the system bleeding the filters is easiest but when at higher than the lowest will/may require 'power bleeding' instead of simple 'siphon pressure' from the tank.

 

[Stu Jackson]

But

Rich, if the tanks are LOWER than the engine, how does "siphon" bleeding work?

And what are the alternates to copper tubing (not on MY boat!)? The Type A fuel hoses seem to appear to be "good" hose. What's the alternative?

When I recently replaced both the secondary (engine mounted) and primary (Racor) filters on my engine (M25 Universal), bleeding was very easy. I opened the nut on the secondary and ran the fuel pump until a small amount of fuel came out, signaling that I'd filled the secondary filter, at which point I shut off the fuel pump with the toggle switch I'd personally installed right next to the filter for that very purpose to avoid spilling fuel. I had earlier filled the new primary filter with injector cleaner to minimize the amount of air in the system. I then used the knurled knob on the engigne to bleed the rest of the air out of the system in less than a minute.

Simple, maybe not "elegant", but it sure works.

I'd put off bleeding 11 years ago because I was afraid the engine wouldn't start again.

Then I got smart, and simply learned how to do it.