Fuel pump leak

[jwwgator]

New to the forum, new to the A4. I have recently purchased a catalina 27 that has sat unused for a couple of years. I have learned alot about the A4 since the purchase. I have successfully diagnosed a fuel supply issue causing intermittent shutdowns and now am having difficulty diagnosing a fuel drip dripping from the bottom of the mount for the mechanical fuel pump. I have replaced the gaskets with gasket material from the local auto parts store that is rated for gasoline and fuel pump mounting. This did not solve the drip. I have since removed the pump and used some permatex high tack gasket sealer on both gaskets and the outside rim of the fuel pump diaphragm itself in order to solve the drip. Upon the last start up, I still have the fuel drip. I am wondering if it is possible that the diaphragm itself may have a small lateral crack that is allowing fuel to get past the seal. Just a shot in the dark. Or maybe the leak is somehow making its way past the screws and bolts that hold the pump together and mount it to the block. I really don't know. Has anyone dealt with a similar issue? Will rebuilding the fuel pump with a moyer rebuild kit solve the problem? I am leaning towards rebuilding the pump anyway just to reduce future failure issues as the diaphragm shows some age and some slight surface cracking in the rubber, but I am more concerned with diagnosing the drip which seems to happen at about 1 second intervals. Any help would be greatly appreciated! BTW, I did not notice the drip until after diagnosing the fuel delivery issue and repeated cranks on the manual priming lever. Don has helped verify my troubleshooting path for the intermittent shutdowns just a few days ago and I thank him for that, but before i bother him again I am hoping to realize some suggestions from the A4 community first. Thanks to all in advance!

[ndutton]

Sounds to me like you have a breach in the pump diaphragm. The problem isn't that it drips, there shouldn't be fuel in the mount area in the first place.

Pull the dipstick and check the oil level, I expect it will be high. Sniff the end of the dipstick for a gasoline smell too. The USCG requires errant fuel from a diaphragm breach to be pumped into the crankcase for containment. Be careful, if I'm correct the fumes are explosive.

[capnward]

I think Neil is right, it's likely your diaphragm is bad. You said it shows age and has cracks in the rubber; it needs to be replaced. That is assuming your reassembly of the pump with gasket material and gasket sealer is sound, and the drip does not begin at the upper gasket area. If the drip really is from the mount gasket, you have gas in your crankcase. So either the diaphragm has a crack, or the seal around it is suspect. I would buy the rebuild kit and do the rebuild. Your pump will no longer leak, and should last a long time. Gasket sealer should not be necessary. Putting sealer on the rim of the diaphragm may not be the correct application. I have a mechanical pump at least 2000 hours old, and it has never given me any trouble. I like to think the use of Marvel Mystery Oil in the fuel, and using non-ethanol fuel, has kept the diaphragm from degrading. Or it may break tomorrow. I haven't looked at it in years.
The possibility of having gasoline in the crankcase from a leaking pump diaphragm is a serious issue, one of the reasons many prefer to use an electrical fuel pump; but I think a mechanical pump has advantages over an electric one. It has more suction, and can overcome small air leaks in the fuel line that electrical ones can't. It does not rely on electrical connections, and does not require an oil pressure safety switch, that you need to bypass in order to prime the fuel line. Instead you just pump the bail to pressurize the fuel line up to the float valve in the carburetor. Once the line is pressurized, any leaks downstream of the diaphragm will appear.
If you have gasoline in the crankcase, you may have to change oil more than once to get rid of it. Beware the fumes. Ventilate the area thoroughly. Don't use a drill motor to pump it out.
P.S., welcome to the forum! What was the successful diagnosis of the fuel supply issue?

[jwwgator]

Thanks for the timely responses guys, I will check the oil asap. I was writing a response to the diagnoses of fuel supply inquiry and must of hit an errant key deleting it all. Due to my eagerness to continue troubleshooting, I will revisit that response later. In short, after much troubleshooting it turned out to be a clogged fuel pickup.

[jwwgator]

My oil does read a little higher than before, but still within the range. I'm fairly certain that i can smell the slightest hint of fuel in the oil. Upon smelling it again, I am almost certain of it. The oil does seem to soak into the paper towel with an almost dieselly effect, also leading me to believe that the two of you guys are correct. I will order the rebuild kit from moyer this morning. I am still uncertain as to why i'm getting the drip. Can't quite wrap my head around that part of it, unless the diaphragm is that compromised, or my gasket making job is that bad, though i have made many gaskets in the past for the upkeep of old detroit diesels. Any suggestions on how to remove the oil from the crankcase. Certainly some sort of hand pump is needed, i suppose. I do not have anything readily available. Maybe i can borrow something from the yard at the marina. I think for safety sake, I will change the oil twice, If no one thinks it is necessary to make more changes. Should i run the engine between changes? I would think that would help in circulating and removing any residuals. I have ran the engine a few times since discovering the leak, for short periods(couple,three minutes). I should have checked the oil sooner, per moyer's manual, but the drip has thrown me off, knowing that a diaphragm leak would be diverted. Never the less, I will be more careful in the future.

[sastanley]

jwwgator, welcome!
I personally would not start a gasoline motor in an enclosed space (a boat) while I have a fuel leak that is actively dripping..the danger is when you flip switches/solenoids and make sparks (like the starter). The fumes in the space are what is dangerous, hence a blower requirement.

The gas in the oil would probably not cause any issues with running, for the purposed of mixing in for removal, but I would solve the fuel drip problem first. It will probably take a couple oil changes to get the fuel out. Most of us use a pump thru the dip stick hole which gets somewhere around 85% of capacity. Other options are extraction thru the reversing gear plate (but you'll likely need a gasket for that after you crack it open.)
They are a little spendy, but I really like the West Marine oil extractor..if you can wait for it to go on sale it is almost reasonably priced, but totally overpriced at retail. A little research tells me that WM likely re-brands the "MityVac 7400" available on Amazon.

Sounds like you know your way around motors, just be sure to follow the instructions in the fuel pump rebuild kit to get the springs & check valves re-installed correctly...I always find them to be a little pesky. Also, the fuel bowl is a little fiddly too..be careful with the bale and alignment, sometimes you don't get it on the first try and pressurizing the pump squirts gas out of the top of the bowl.

[jwwgator]

Thank you for the comments. I will certainly address the fuel leak before changing the oil and then running the engine . I have run the engine a couple of times since discovering the leak, each time with all hatches open and the blower hose placed right at the point of drip. Unfortunately i cannot assess the drip or possible repair of the drip without cranking her up, as she only seems to drip under running pressure and not when working the priming lever. I have already ordered the rebuild kit along with a spare alternator belt. I should have asked the forum what some good spare parts would be to carry. If any suggestions are added to this post, I may have time to call and add to my order. Thanks again to everyone.

[JOHN COOKSON]

I should have asked the forum what some good spare parts would be to carry. If any suggestions are added to this post, I may have time to call and add to my order. .

It depends on how you use your boat. In\out of the harbor for day sailing, over night cruises, or long distance passages?
Do you have an EI or points? Some coils are susceptible to over heating when a EI is used.

TRUE GRIT

[jwwgator]

I have an electronic ignition and am currently in harbor in VA awaiting hurricane Mathew. I will be headed to the Florida Keys at the end of the month as that is my home area. I have recently left Annapolis MD.The boat will get lots of use. This is my first A4 and first inboard gasoline engine Last boat was a trawler with a Perkins 6.354 diesel. Great engine btw!

[JOHN COOKSON]

Form member edwardc is planning a similar trip. I presume you have been reading his posts.

TRUE GRIT

[edwardc]

Form member edwardc is planning a similar trip. I presume you have been reading his posts.

TRUE GRIT

Yes, we're still sitting at the dock, snug in our hurricane-hole on Rock Creek, waiting for Matthew to work itself out.

[jwwgator]

I have not, but i will check out his posts. I edited my last post and it does not seem to have posted, so here goes again. Hopefully i do not strike whatever key i have now struck twice that causes my entry to go blank! Since you say that some coils get hot with ei, i thought that more info was certainly needed. My coil does get somewhat hot. I called Don to see how hot it should get, but obviously that is hard to describe. My initial shut down was after about 4 hrs. run time under light load. 1500 rpms. She would not start back up for about 45 minutes, then ran for 1 hr. or more before shutting down again. Both times as if the ignition was shut off. Not long after those episodes, I replaced a battery and got under way again(just needed a new battery, not to try and solve any issue). I ran into some rough weather on the chesapeake, which noaa did not warn me of until i had been in it for a couple hrs. This is when the fuel starvation symptomatic shut downs began. I eventually cleared the pick up, and the engine ran for over an hour before shutting down again. At that point I called Don(as mentioned before) to ask a couple of questions and get some reassurance as to my troubleshooting. I asked about the coil heat and went through the shut down symptoms. He confirmed that i was on the right track and to leave my carb alone, as after the engine shutting down again, that would have been my next move. At the last shut down, i was low on gas, so i refueled and then let her run for more than two hrs. with no problems. Thinking i had solved all the problems, i then got up the next morning to get under way, and with one last trip down into the hatch that acceses the fuel side of the bilge, I discovered the fuel drip. With hurricane Matt bearing down, and many troubleshooting episodes, not to mention replacing the exhaust system(as i have stated before, the boat sat for a while) just to continue the fuel starvation troubleshooting, I decided that it was good idea to remain in port for the month and finish working out all the kinks. I said all that to say this, I'm afraid that once i rebuild the fuel pump and hopefully solve the fuel leak, that i will be revisiting the ignition shut down issues. Fingers crossed that it was fuel all along, but the original symptoms had ignition shut downs written all over them causing me to continue chasing the ignition before finally finding the clogged pick up. I tried another coil, which only got hot way too fast. I went back to the original coil. I found a separating coil wire, which initially did not solve the shut downs as it was still shutting down due to fuel. If i am lucky, maybe that was what caused the initial shut down. Anyway, I cannot find a brand on my coil, but it has the numbers 27270 printed large, says use without external resistor, made in the usa and below a white line (all other words and numbers are written in white) are the numbers 1299(with what could possibly be other numbers missing but i am leaning heavily towards the 1299 just being smeared a little) I think that i have all relevant info posted in this post, but any questions are welcome and all help is greatly appreciated. Thanks to all. Oh, and the electronic ignition was installed by the previous owners long time mechanic who was supposedly well versed in the A4.

[jwwgator]

And i got that one posted without screwing up! phwew! Hey edwardc!, I'm in gloucester point. Be headed out at the end of Oct. with several other vessels, maybe I'll see you along the way. 27 catalina, Magic.

[jwwgator]

Or not, looks like you have a different destination. I am headed to the keys!