Need Engine Help (Gurus Wanted)

Sapperwhite · #1 (**permalink**) 05-24-2008

Right now I'm anchored just outside of a channel (sprint card rules) and the engine is giving me hell. I replaced the fuel tank recently and had a 2micron racor in just to filter out any metal dust from the new tank. I thought that fine filter might be chocking the engine some. I dropped anchor just in time before the engine quit. I changed the racor out to a 30micron (my normal). I bleed the fuel lines and had it running for 30minutes while still at anchor. Then it started dying down and kaput. Bleed again and is running now.

In between bleeds I saw little bubbles coming up around the tightened down yanmar filter bleed nut. It has a banjo and is tightened.

Is air getting pulled into the system through a leaky banjo? Its on the pressure side, that would mean fuel should come out from a leak there.

WTF? Suggestions.....

timebandit · #2 (**permalink**) 05-24-2008

I am guessing you did not have any of these problems before changing tanks I would check the hose conections from the tank to the filters--mybee a hose clamp that is not tight.

Might wanna get a couple new banjo washers in the mean time try turning the washers up side down.

Quote:

Originally Posted by Sapperwhite

Right now I'm anchored just outside of a channel (sprint card rules) and the engine is giving me hell. I replaced the fuel tank recently and had a 2micron racor in just to filter out any metal dust from the new tank. I thought that fine filter might be chocking the engine some. I dropped anchor just in time before the engine quit. I changed the racor out to a 30micron (my normal). I bleed the fuel lines and had it running for 30minutes while still at anchor. Then it started dying down and kaput. Bleed again and is running now.

In between bleeds I saw little bubbles coming up around the tightened down yanmar filter bleed nut. It has a banjo and is tightened.

Is air getting pulled into the system through a leaky banjo? Its on the pressure side, that would mean fuel should come out from a leak there.

WTF? Suggestions.....

knothead · #3 (**permalink**) 05-24-2008

Quote:

Originally Posted by Sapperwhite

Right now I'm anchored just outside of a channel (sprint card rules) and the engine is giving me hell. I replaced the fuel tank recently and had a 2micron racor in just to filter out any metal dust from the new tank. I thought that fine filter might be chocking the engine some. I dropped anchor just in time before the engine quit. I changed the racor out to a 30micron (my normal). I bleed the fuel lines and had it running for 30minutes while still at anchor. Then it started dying down and kaput. Bleed again and is running now.

In between bleeds I saw little bubbles coming up around the tightened down yanmar filter bleed nut. It has a banjo and is tightened.

Is air getting pulled into the system through a leaky banjo? Its on the pressure side, that would mean fuel should come out from a leak there.

WTF? Suggestions.....

A guru I most definitely am not. But you're describing something similar to an experience I had recently.

The engine would run for awhile then stop. We saw that there was air in the water separator/ filter. We bled the system. It ran for awhile and stopped.
After doing this a number of times it was discovered that the end of the pickup in the tank had sucked up what appeared to be a wad of Teflon tape. It stuck at the end of the pick-up. It wasn't until a high pressure pump was attached to the line that it passed (was sucked) through the line.
We suspect that though the line was partially clogged there was enough fuel getting by the wad that the engine would run until it created enough of a vacuum in the line to cause it to stop.
What a pain in the butt that was.

Sapperwhite · #4 (**permalink**) 05-24-2008

retightening everything now.... found the hose joint on the low side of the fuel pump leaky, got a small turn on it when tightening. I can't see any air going through the Racor bowl, so I'm leaning towards everything downstream of it. Retightening everything regardless.

Thanks for the turn the banjo upside down tip.

Maine Sail · #5 (**permalink**) 05-24-2008

If it's on the pressure side then no air is being sucked in, hence the bubbles. It's kind of hard to blow bubbles whilst sucking.... In either case you do seem to have a leak. I once took a banjo washer to my wet stone/diamond stone, for sharpening knives, and "smoothed" it over. It worked after that. If you don't have that you may try a piece of 400+ grit sand paper on a piece of glass or a very flat and hard surface.. Flipping it over might also work..

Just know that many secondary filters, the ones mounted on the engine, are between 2 and 5 microns so using a 30 may plug your engine mounted filter significantly faster if your tank is not totally clean. My Westerbeke's primary filter is rated as a 3 uM/micron so I use a 10 on my primary Racor 500..

If you know your secondary filter is a 10uM then use a 30uM primary. However if your secondary is a 2uM or 3uM use a 10uM primary.. Hope that makes sense..

Sapperwhite · #6 (**permalink**) 05-24-2008

Quote:

Originally Posted by knothead

A guru I most definitely am not. But you're describing something similar to an experience I had recently.

The engine would run for awhile then stop. We saw that there was air in the water separator/ filter. We bled the system. It ran for awhile and stopped.
After doing this a number of times it was discovered that the end of the pickup in the tank had sucked up what appeared to be a wad of Teflon tape. It stuck at the end of the pick-up. It wasn't until a high pressure pump was attached to the line that it passed (was sucked) through the line.
We suspect that though the line was partially clogged there was enough fuel getting by the wad that the engine would run until it created enough of a vacuum in the line to cause it to stop.
What a pain in the butt that was.

I inspected the inside of the new tank before installing, so this might be a long shot......but anything is possible on a boat.

Sapperwhite · #7 (**permalink**) 05-24-2008

Quote:

Originally Posted by halekai36

If it's on the pressure side then no air is being sucked in hence the bubbles. It's kind of hard to blow bubbles whilst sucking.... In either case you do seem to have a leak. ..

the filter bleed nut bubbles after shut down, so thats an outie leak, found the low side of the fuel pump leaking after shut down...probably the culprit, retightening and we'll see.....what fun we're having this weekend! Good thing PSC has a cockpit sole that lifts off for engine access...

artbyjody · #8 (**permalink**) 05-24-2008

Quote:

Originally Posted by Sapperwhite

the filter bleed nut bubbles after shut down, so thats an outie leak, found the low side of the fuel pump leaking after shut down...probably the culprit, retightening and we'll see.....what fun we're having this weekend! Good thing PSC has a cockpit sole that lifts off for engine access...

Sapper - it could be that spring on the outlet of the fuel pump is bad. I had to replace mine (entire fuel pump) as the PO had overtightened the outlet it and it never set properly. Removal of the bolt brought out the spring in a badly deformed fashion and I was never able to tighten it (due to the spring). If you have a spare fuel pump and the tightening doesn't work - it may be a good time to swap that out, as you will not be able to rid yourself of that problem ( if that is indeed the case)...

Sapperwhite · #9 (**permalink**) 05-24-2008

Quote:

Originally Posted by artbyjody

Sapper - it could be that spring on the outlet of the fuel pump is bad. I had to replace mine (entire fuel pump) as the PO had overtightened the outlet it and it never set properly. Removal of the bolt brought out the spring in a badly deformed fashion and I was never able to tighten it (due to the spring). If you have a spare fuel pump and the tightening doesn't work - it may be a good time to swap that out, as you will not be able to rid yourself of that problem ( if that is indeed the case)...

It's a new fuel pump, see my pump thread:

http://www.sailnet.com/forums/gear-m...mp-damage.html
damn links!

search threads for "2gm fuel pump damage" sorry

the new fuel pump is leaking some too....ggggaaaaaa!!!!

Sapperwhite · #10 (**permalink**) 05-24-2008

she purrs

I'm going to wait here an hour. last time I bleed her she quit after 30 min, so i'll play it safe....

lessons learned:
better inspection after major work
recheck after engine gets hot
get new banjos and carry spares (of all the spares I have banjos ain't one of em)

thanks for the tips on the bajos again guys.....hope this time is the last