Check my (newbie) thinking on fuel

[NorthCoastJoe]

On my engines, after replacing fuel filters I crack open the fuel line leaving the engine filter, and then pull the tank vent line off and blow into it. It pressurizes the tank and forces fuel through the system. Easy bleeding no special pumps or anything else. It is also safe because you only develop about 1 psi. If there are any air leaks along the way you will see them weep.

If your lift pump goes bad it would most likely be a blown diaphragm and if you use an electric pump to push fuel to it you will fill your crankcase with fuel. If you go that route bypass the engine lift pump.

I use an electric pump to move fuel from the main tank to my day tank and it really moves a lot of fuel fast through a Racor.

[sailingchiro]

You are running out of fuel, obviously. Either you are creating a vacuum or sucking air. But which? That is the question?
Vacuum, something is plugging up the pickup tube or the 90 angle at the top of the fuel pick up.
Air leak, the Racor, fuel line, or fittings have a leak. Both will leave a stain in your shorts while docking when the engine dies.

Personally, I would take a (new) fuel line from the Racor and put in day tank (5 gallon fuel tank) and rule out anything prior to Racor. If the engine runs without any problems then it is fuel line, pick up tube, junk in tank, fuel cutoff, or fittings to tank. If it still has problems, then run fuel line to engine filter from day tank.

This method will eliminate alot of headaches of trying to figure it out which part is the problem. Many of us been there done that. Only to figure out the problem isn't fixed while docking in crowded marina with a strong wind. Then the engine stops.
Please limit your problems to before your Racor or after your Racor. If you don't, it will drive you crazy. Trust me.

[thunderhoof]

Verify that the fuel lines from tank to filter or to engine are not clogged. I, in an older boat, found a 4 foot horizontal run completely clogged with a sandy algae. Nothing to do but to replace it.

[Uncle Bob]

Given that you changed filters, did you use the new "o"rings provided with the new filters, especially the racor filter, the small ring for the t bolt on the top. Don't ask me how I know this.

[PanamaJim]

You might try checking the hose clamps first. The most likely problem is a small air leak. If the engine runs for a while and stops it is most likely bad clamps on your fuel hoses. It's a simple fix, but replace the clamps with the best clamps you can buy. Don't skimp. Don't reuse old clamps. Fuel problems are the worst. Bleed a gallon of fuel from your primary pump after isolating the leak, till you are absolutely sure you have no air bubbles what so ever. Bleed even more if you need to. Obviously check for bubbles in the rancor too.
I find a fuel leak by sprinkling baby powder on the hoses. The powder will become wet and show immediately. It's unorthodox, but so is sailing.

[jamhass]

I had a sudden fuel starvation issue that took me some effort to find. Turned out the manual emergency fuel shutoff had been inadvertently shut. Since the boat is new to you, you might not be aware where it is -- or if one exists at all.

[djousset]

Thanks for all the good suggestions, it gave me a checklist to work off of.

Here’s where I am:
I believe the tank vent is fine (I opened the deck fill cap and there was no swish sound)
I reseated both filters and checked the seals/gaskets. All looked good.
I cleared the fuel line from the tank to primary filter and primary filter to lift pump. Removed, blew them out, reattached and tightened all hose clamps. Seems fuel is flowing fine from the tank into the racor primary.
I turned the engine over to turn the cam in case the lift pump wasn’t engaging properly. I have no idea if I did this properly.
I forgot to check the tank pick up but again fuel seems to be making its way to the racor fine.

I still can’t seem to get fuel to the secondary filter despite LOTS of time manually working the lift pump. Frustrating. It seems the problem may be with the lift pump itself? Can I leave it there and just bypass it with an electric lift pump? Is its only job the delivery of fuel to the secondary pump? Will a squeeze bulb do the same thing? How much will an electric pump draw?
Thanks as always for the help.

[wingssail]

Originally Posted by djousset

Thanks for all the good suggestions, it gave me a checklist to work off of.

Here’s where I am:
I believe the tank vent is fine (I opened the deck fill cap and there was no swish sound)
I reseated both filters and checked the seals/gaskets. All looked good.
I cleared the fuel line from the tank to primary filter and primary filter to lift pump. Removed, blew them out, reattached and tightened all hose clamps. Seems fuel is flowing fine from the tank into the racor primary.
I turned the engine over to turn the cam in case the lift pump wasn’t engaging properly. I have no idea if I did this properly.
I forgot to check the tank pick up but again fuel seems to be making its way to the racor fine.

I still can’t seem to get fuel to the secondary filter despite LOTS of time manually working the lift pump. Frustrating. It seems the problem may be with the lift pump itself? Can I leave it there and just bypass it with an electric lift pump? Is its only job the delivery of fuel to the secondary pump? Will a squeeze bulb do the same thing? How much will an electric pump draw?
Thanks as always for the help.

I did mention this, maybe it is not possible for you, but if you pressurize your tank by blowing into a vent pipe it will force fuel to flow all the way through to the secondary filter and beyond, to the injector pump. This is quick and easy and may also reveal leaks (fuel under pressure will leak out).

This may not solve your problem but it could eliminate some issues.

[Compass790]

Have you tried taking the output line off the fuel pump to see if its pumping?
You can feed the lift pump with a temporary line from a diesel jug to check lift pump is functioning.
You can leave the lift pump there & just bypass with an electric pump. I think they only draw 1-2 amps.
I'd try wingsails suggestion too.
You can just put a squeeze bulb in the fuel line before the fuel filter but if the lift pump is stuffed that wont help but it certainly helps with bleeding.
Yes the lift pump is only there to supply fuel to the secondary pump which is called the injection pump.
The only way to tell if the lift pump is off the cam & working for it's full stroke is by feel, an experience that you dont have.
Sometimes they just dont work for s**t

If you take the banjo bolts off the lift pump be sure to anneal the copper crush washers, i.e heat them red hot on the stove & allow to cool.

[skipmac]

When I had the same problem IE fuel to the Racor but air in the secondary I did all the same things you have: remove hoses, clear, reattach, tighten clamps, checked Racor o-rings, etc. After multiple tries I confirmed that fuel was reaching the Racor but air leaking through the Racor so no fuel reached the secondary.

Here's a sure but messy way to confirm. Get a quart or so of fresh diesel in a very clean container. A clean, dry, plastic water bottle will work. You say the Racor is full so open the secondary filter and fill it. Be very, very careful not to get any dirt in the filter.

Now loosen a fuel line at one of the injectors and try the hand pump.

[Compass790]

This is what I mean for primer bulb:https://www.amazon.com/Pactrade-Mari...s%2C342&sr=8-3


And this is the sort of pump that will work.https://www.amazon.com/JDMSPEED-Univ...s%2C352&sr=8-3


I'd guess you will find them at an auto chain store to avoid waiting for post.


Don't be too quick to condemn your lift pump though. As your problem occurred when you did filter change I'd think air is more likely. I reckon you need to test lift pump first. They are easy to dissasemble & look at diaphragm too but I'd just try with another fuel feed first.

[mlydon]

You will know if the lift pump lever is ‘on the cam’ because you will get short, ‘metalic’ strokes.....you’ll feel the pump lever touching the cam. You need to rotate the engine only 1/4 turn or so- don’t crank it for ages, you might end up in the same spot....

The lift pump when NOT on the cam will have a longer stroke, and you’ll feel a ‘rubbery’ resistance as fuel is pumped before the mechanism bottoms out.

In the event you want to add an electric lift pump, I can recommend the facet solid state pumps - typically the 40007 if I’m not mistaken- 5 psi, 12v. They make a bunch, to different specs....

[Compass790]

Originally Posted by mlydon

You will know if the lift pump lever is ‘on the cam’ because you will get short, ‘metalic’ strokes.....you’ll feel the pump lever touching the cam. You need to rotate the engine only 1/4 turn or so- don’t crank it for ages, you might end up in the same spot....

The lift pump when NOT on the cam will have a longer stroke, and you’ll feel a ‘rubbery’ resistance as fuel is pumped before the mechanism bottoms out.

In the event you want to add an electric lift pump, I can recommend the facet solid state pumps - typically the 40007 if I’m not mistaken- 5 psi, 12v. They make a bunch, to different specs....

Great job on the lift pump priming lever feel description mlydon. I was trying to think how I could describe the 'feel' to OP but couldnt do it, just put it in the too hard basket but you nailed it

[Ramona]

I have one of those fuel pumps Compass790 provided the links for. It's before both filters and I power it up with jumper leads to push fuel through the system and to bleed. Then I disconnect the leads. I tossed my Racor because I could not stop the air-leak at the O ring at the handle. Instead I installed a quality Chinese water separator and all the problems disappeared.
https://www.ebay.com.au/itm/27468681...xoConkQAvD_BwE

[djousset]

Hopefully I'm in the final stretch.... I installed a bulb primer between the racor and the lift pump and was able to bleed the system through the secondary filter. I cleaned everything and put absorbent cloths underneath so I could see if they were any leaks, all dry. I followed the lines up to the injectors and loosened the bleed screw on the return line to the tank, and started pumping again. I noticed no air or fuel coming out of the injector exit line. After a v e r y l o n g time I decided to give the engine a try and it did start but died within 5 to 10 seconds. I went back down and pumped more and the same thing happened. I feel like if I was able to keep squeezing the bulb while I was turning the engine over maybe it would catch and purge itself? Am I on the right track? One person pumping and one turning the engine over?