fuel system troubleshooting

[seburnett]

I purchased a CP27 earlier this summer and I'm pretty sure sure I've fixed the overheating problem the previous owner lied to me about, but now I'm having a new problem.  The engine starts up and runs, but the rpms fluctuate and the engine dies.  We took the fuel line and return off and ran the engine off a jerry-can of diesel without problem.  So, my original thought was fuel contamination since the boat had been sitting awhile before purchase (though this had not occurred during the sea trial in June or two subsequent times out in August).  I replaced all the filters and had the fuel tank cleaned.  Problem still occurred.  Took off the fuel pickup, expecting gunk on a mesh cover but found neither.  No obstructions of the fuel pickup.  Found a small crack in the fuel hose where overtightening the clamp had cracked an older hose, cut off that section, and still had the same problem.  Replaced the hose in case there was another perforation introducing air that might be under the fuel line in the jerry-can, but not when attached to the fuel tank.  Checked for evidence of an obstructed vent hose for the fuel tank but found none.
Today, I found that it runs great on the jerry-can of diesel, unless I still have the fuel hose connected to the fuel pickup, in which case the RPM fluctuates and the engine dies as if I am running it off the fuel tank.  I suspect that the fuel lift pump is beginning to falter and unable to draw enough fuel consistently through the fuel pickup.  I'm very much a neophyte around engines of any kind so I thought I would check if anyone had other ideas that I should consider before spending $250+ on a fuel lift pump. 
Scott

[newt]

Scott, can you disconnect the fuel line just before the engine and does fuel flow easily? You might have some gunk in the fuel lines somewhere. If it was something else, then the Gerry can test would not work so well. Also, has the fuel tank been cleaned? I would do that before I bought a new pump.

[seburnett]

Fuel line downstream of the pump flows, but I don't have an easy way to gauge if it flows well enough.  It seems downstream clogs of the fuel line would be problematic if I ran in on the fuel tank OR the gerry-can, which is not the case.  The fuel tank has been cleaned.

[Allure2sail]

Hi:
I had some fuel delivery problems as well. First I would like to ask you how the tank was cleaned. Was it taken out of the boat or did someone just "polish" the fuel over and over again? I made a fuel polishing setup with a spare lift pump and water separator / fuel filter I had. I used 10 micron filters and I have to be honest with you it never really got all the crude out of the fuel tank. I ended up taking out the tank putting in it what they call polishing stones. They are used in the tumbling machines that are in use out in industry. I put in 100 stones (they are about the size of a quarter) with about a gallon of gasoline. Then I rocked it back and forth on each surface for about five minutes for each surface. Of course you must take out the sending unit and seal off the hole before the rocking and flushing process. You count the stones so you know you got them all back out at the end. I would pour the fuel out and thru a white paper coffee filter to check it. When the gasoline came out clean with no residue left in the coffee filter you know you are done. It took me three complete series of rocking and flushing before it came out clean with no resdie left in the filter once it drained thru it. The other thing I would look at is the mesh screen filter in the bottom of the lift pump. You may have to take the pump off to take the bottom cap off if it has never been apart before. If you choose to replace the lift pump I found a NAPA store to be the cheapest. The engines fuel needs can easily be taken care of by the smaller pump they sell. I believe the one I bought from them said FACET on it. There is a way of monitoring fuel flow with a vacuum gage, it tells you when to change your filter and if the lift pump is pulling okay. If you search the internet I'm  sure you will find an article on setting one up. Not much else I can add, except good luck.

[seburnett]

The tank was not removed but a company came out to spray out the interior and polish the fuel.  Good point about the lift pump.  I may take that off and look at the base as you mention.  Thanks for the recommendation on the Facet pump.  I have read that they are not meant for continuous pumping as might be expected in cruising, though some appear to have had no problems.

[Caboose]

Fittings - Check fittings.
I've seen where all the hoses are fine and even replaced, but there was enough trash to form a partial blockage in fuel system.

Place your "Jerry Can" below level of normal fuel pick-up to check "lifting power" of fuel pump before buying a new pump.
Your fuel line may be loosing it's resistance of staying open. Think along the lines of your water pump on your car. The suction hose has a metal spring in it to keep it from "sucking closed".

Test, check, adjust, clean all you can before spending $$$.

[Allure2sail]

The lift pump pulls the fuel thru the water separator / filter. I do believe the injector pump takes over from there. If that is the case then I assume a vacuum gauge would go between the lift pump and the water separator / filter to measure how hard it had work to pull the fuel thru. When the filter starts to get dirty the vacuum reading would rise because it has to work harder to pull the fuel thru. After a certain level it is time to change the filter. I "think" that's the way the fuel delivery system works, but not 100% sure. Also I've been calling the fuel filter closes to the engine the primary and the water separator / filter the secondary. Can anyone verify that? The FACIT lift pump looks just like the one I took off (which there was nothing wrong with after all). I don't know if any of this will help you but at least it explains a little more about fuel systems. The "FASIT" pump I bought from the local NAPA store was I believe under a hundred dollars. There is a fine mesh screen inside the bottom of the pump and it is pretty easy to check. I have a extra lift pump on the boat that I could send you to try but I don't know if that would help you, sending it might be a nightmare because of the fuel smell.

[Allure2sail]

Hi:
Going to the marina today and I'll get the part number off the FACET lift pump. Went on the Internet last night and there are a number of different model FACET lift pumps. I could not get them to show up on the NAPA website.
Bruce

[seburnett]

I've been looking more into pumps and believe I've found the one you are referring to.  Is this it?
http://shop.torresen.com/ships_store/?p=details&ident=479043

[Allure2sail]

These pumps are exactly like what both my ComPac 27's came with. Both of these units will supply your two cylinder M12 with more fuel than it will ever need. Considering the engine (even at maxed rpms) might use a gallon an hour. I will get the numbers off of the three pump units I have tomorrow. I must add this to the mix. Make sure you have a good ground connections on the pump. Mine has a ground wire going from the pump body to the mounting bracket and another wire going to the engine to complete the ground path. When I replaced the pump I ran a new tinned wire lead to the engine itself. The old ground wire to the engine looked pretty tired. You should always be able to hear the clicking noise from these pumps when the panel key is in the run position. Next time the engine dies open up the lazarett door on the starboard side and listen for the pump clicking. If it's not wiggle the wires and see if it start to make the clicking noise again. You might have just have an intermittent ground problem with the lift pump. If it does stop pumping I would suspect that the injector pump will lose its prime and thus the engine will stall. It looks deceiving because the clear plastic bowl on the water separator / filter (the secondary filter) will still have fuel in it but the lift pump has stopped passing it on to the injector pump. I'm certainly not a diesel mechanic so if I made some incorrect statements PLEASE JOIN IN !!!!
http://www.russellsnewoldparts.com/ELECTRICFUELPUMPS.html
This pump would also work fine....
http://www.yachtsupplydepot.com/mechanical-supplies/fuel-pumps/facet-cylindrical-solid-state-electric-fuel-pump-476459e/prod_23436.htm

[Catalina9405]

Scott,

I had some similar fuel issues with my Compac 27 (1988) after I bought it.  I attempted to clean the tank myself.  What I found was that there was so much black sludge, likely algae growth, that i could not get it all removed.  I took the tank to a radiator shop and had it professionally cleaned (steam, powerwash, and chemical bath).  It looked like a new tank when I did a mirror inspection.  I replaced all of my fuel line both supply and return as well as both filters. 

Once I started running the engine it was still suffering from fuel starvation.  I checked the flow from the electric fuel pump, the same one someone else had a pic of from torrensons.  The fuel pump barely had a trickle coming out of it.  This is a serviceable fuel pump.  There is a screen inside of it that filters the fuel on the intake side.  When I took it appart (corroded) I found the screen was completely clogged with the same black sludge.  I rebuilt the pump cleaning everything with carb and choke cleaner.  I was amazed at the amount of fuel the pump then pumped.  Two years later all is working just as well with no further problems.

I would also recommend that if you have to replace the pump to use an automotive pump that is rated for diesel.  You can pick up a pump for around $30.00 that will provide the required flow and pressure.  And for that price you can carry a spare just in case.

Chad

[peterg]

When I bought my Compac 27 last Fall, it had been sitting on the hard for two years. I was going to motor it about five miles to my dock, so I told the marina to do a full service on the boat, so that I wouldn't have any surprises on the motoring trip home. In the past, I've always done the maintenance on my diesel engined boats, as I had gotten reamed by an Annapolis boatyard when I bought a boat down there in 1997. I guess that I should have done the filter and fluid changes myself on the CP27, and at least I would have known that they were done correctly. Long story short, I brought the boat home, and since my schedule was really hectic for the next bunch of months, I had infrequent occasion to use the boat, sailing maybe a dozen times, and putting only a few hours on the diesel (M2-12 Universal). Anyway, winter approaches and I stripped the boat, changed the oil and filter, and headed up the bay five miles to Cedar Creek, where the boat was to be hauled and stored for the winter. The diesel stopped dead at the mouth of Cedar Creek, with a 20 knot southerly blowing me out of the channel. I kept the ignition on so that, perhaps the  electric fuel pump might self bleed the system and I could re-start the diesel. After about a minute wait, the diesel was able to be re-started, so I kept the RPMs at 2000 and proceeded to motor through the mile long shallow and narrow channel to the marina. As I turned around the last red marker before the travel lift slip, the diesel gasped and shut down. I was making about three knots with the wind behind me, and I glided into the travel lift slip, jumped onto the dock, and stopped the Beagle, and secured her to the finger pier. This was last Tuesday. The boat was hauled, washed, and put in her winter cradle. I went to the marina today to see if I could trouble-shoot the problem. The first thing that I found was that the original marina who was supposed to do a full service (and who had "maintained" the boat since new), had put a 2 micron filter on the primary Racor filter, and a 10 micron on the secondary filter on the engine.....the reverse of what I would have done. I put a 30 micron on the primary, bled the system, and ran the engine for twenty minutes at 2000 RPMs and it seems to be fine. The ground wire on the pump was also poorly attached, so I relocated the pump from the insulated bulkhead to a more solid attachment, and cleaned up the electrical connections. The pump filter was very clean after running downstream of the misplaced 2 micron filter.  My question to other CP27 owners is, what spin on filter do you use on the secondary filter (on the engine)? I had a NAPA 3390 10 micron spin on filter, that the original marina put on last November. I would prefer a 2 micron filter for the secondary- any suggestions?  To further diss the work that some marinas "professionally" provide, I figured that I'd check the air filter while I was folded up in the starboard crockpit locker. The paint was still on the threads of the securing machine screws, indicating that the filter had not been serviced since the boat left the factory, and, indeed, the foam filter element had been digested by the intake years ago. Time to put a proper filter back on line, and never recommend the marina that "serviced" the boat for the last twenty years! I will also remove the fuel tank and do a thorough cleaning on it before next Spring, as well as new fuel lines, and perhaps, a new pump- I hate being stranded by a balky diesel when all the sails are off the boat!!!

[Allure2sail]

Filter chat...
I have not been able to find a 2 micron filter for the engine itself (I call that one the primary filter) so I use a ten micron. The filter on the water separator / filter is a thirty micron (I call that one the secondary). I agree with everthing else you last two guys said. One last thing to mention is that the gas tank sits on a wooden board which must be subject to never getting totally dry. The tank being made of aluminum the bottom surface had the starting signs off corrosion, if you do take it out of the boat inspect the bottom side for corrosion. If anyone has the part number for a 2 micron filter for the engine itself I could sure use it All the numbers I could find when I looked up the specs turned out to be ten micron filters. The idea setup is like you said to pass the fuel thru a ten micron first and then a two micron next.

[seburnett]

Thank you all for your suggestions and comments.
The fuel lift pump currently on the boat doesn't seem to have a filter.  I also can't see any brand or model info on it whatsoever. 
The strange thing about my current problem is that the engine only runs fine when I have the fuel lines detached from the fuel tank and stuck in a gerry can of diesel.
It won't run when I try the same thing with the fuel pickup from the tank mounted on the fuel line but stuck in the gerry can.  I've checked the fuel pickup and it is free of obstructions and does not leak.
This morning I ordered the pump linked by allure2sail previously.
http://www.yachtsupplydepot.com/mechanical-supplies/fuel-pumps/facet-cylindrical-solid-state-electric-fuel-pump-476459e/prod_23436.htm.
According to the manufacturer it is the same pump as the 476459N (with only different packaging), which is listed by Torresen Marine as a cheaper substitute for the Universal part (#301385).

As for filters, I need to get on the boat and look, but when I replaced them earlier this summer (upon purchase), I seem to recall using a 10 micron filter primary and 2 micron secondary.  Then again, maybe that is just wishful thinking on my part.

[Allure2sail]

Hi:
If the new lift pump does not do the trick (sounds like a good bet) I can send you the the pick up out of a spare fuel tank I have to try. I'll clean it up with carburetor cleaner to get rid of the diesel smell and put it in a sealed Tupperware container. Hope your problem has been solved. We had a good fuel system tread going for awhile......
Bruce
S/V Allure