Clint,

It sounds like you are on the right path. Sounds like a fuel problem. First step would be to get both seperators open and cleaned out. Something I have learned from many years of boating a carbureated (spelling?) boats, is that fuel problems are rarely consistent.

-Shane

Agree. Is there also an inline filter after the fuel pump? If so, it's often the culprit. That filter is common with the Quadrajet carbs, don't know about the E'brocks.

Thanks for the replies.

One symptom I failed to mention was when my mechanic was trying to tune the port 1409 after it started stalling he pointed out that he was seeing quite a bit of water which was causing some back-firing. Question - is it common for this problem to happen only on one engine and never effect the other? Also, we did wire the choke to ballast resistor - how could that cause similar symptoms? I've never had cold start issues - thus I assumed that choke operation wasn't an issue and wiring to the ballast resistor was ok.

I like the outboard tank/transfer valve setup - seems like a simple way to isolate things.

/Clint

Check the anti siphon valves. They are right at the fuel outlet of EACH TANK. I had similar problems when I got my boat and did all the normal stuff...drained the tanks with an electric fuel pump, changed fuel filters (I have 3 on each engine in my boat one IN the carb, one in the line AFTER the fuel pump, one in the line BEFORE the fuel pump), changed the fuel water separators, checked vent lines. I did have water and crap in the tanks...after the water issues were dealt with I still had problems. Boat was still dying. I cut open filters...they were clean, I drained water seperators in to jars and the fuel was clean with NO WATER but I STILL had probs. Turns out that the anti siphon valves were all clogged/gummed up. The boat would run at idle all day, it would run at speed for 10,20,30 mins sometimes even longer then fall on its face. Most of the time I was able to restart but would die soon after again. I pulled the anti siphon valves out and they were packed with all kinds of crap. I replaced them with brass pipe for now so that I know I have full flow and the filters can do their job for the rest of the fuel that I have in my tanks (about 100 gals each side still). when I refill I will replace with new ones. Since I did this I have not had the boat die YET! YET is a KEY WORD!! Hahahah What I THINK was happening is the fuel would flow enough to run the boat for a while and then eventually the pickups in the tank would suck up some more garbage and completely block the fuel flow. Engine would die. I would scrammble down, change a fuel filter and drain the water seperator (both spin on style like an oil filter) thus breaking the vacuum/siphon and the crap would drain BACK to the tank allowing fuel to flow again until it would happen again and I would repeat the entire process. What really clued me in was the LAST time it happened...FRESH filter, FRESH water seperator less than 5 mins run time and it died, spun both off, drained, saved and put new on again...3 mins later did it again same engine, pulled drained saved put new on and 3 mins later did it again. I limped the boat in to where we were heading and relaxed... I was out of new filters and seperators. Dinghyed in and bought more for the return trip. Change 3 more times on the return trip. and yes if your thinking this is getting expensive your RIGHT! I took all the old filters and seperators home and cut them open. Thats 12 cans if your keeping count and almost 3 full gallons of CLEAN GAS from draining. I couldnt have filled a thimble
with the amount of stuff that came out of all of them filters/seperators combined and there wasnt a drop of water to be seen in any of the jugs. HOPEFULLY I ahev cured my issue now and I guess only time will tell but I would say CHECK the anit siphon valves and if they are clogged at all ...GET RID of them for a while and let the filters do their job.

(btw, this excellent thread belongs in mechanical/engine).
Last Feb, our noted Dr Jeff (Fastjeff) posted these points worth repeating here:
1. No in-carb filters allowed (unless one has done # 2 below).
2. A good sized, METAL, in-line filter AFTER the fuel pump.
3. NO fuel filters (fine filtration) BEFORE the fuel pump.
4. A strainer (coarse filtration) located before the fuel pump. Usually doubles as a water separator (critical with "evil-nol" gas).
5. Anti-siphon valves (if equipped) clean and operating properly,
6. Tank vent not blocked by ???
7. Fuel pump (mechanical) producing 5 to 7 psi fuel pressure (via a test gage).
8. Enough fuel in the tank to reach the pickup ON PLANE
9. No kinks or crushed metal fuel lines in the system.
10. Shut off valves not allowing air to be drawn in. (Don't laugh. The stock valves on my boat leaked enough air in to totally screw up the Flo Scan. They do NOT leak fuel, however, or they would be outta there

The anti-siphon valves--if you have them--are in the fittings right at the fuel tanks.

Jeff

I have a 1980 28 ft. similar problem. 1st changed coil, same problem. Next removed the check valve., same problem. Next replaced all filters twice, same problem. next changed fuel pump, same problem. Next changed pick up and reluctor problem solved! After solving this problem ran like a champ until the ballast resister broke, now repaired. Ps if the ballast resister is bad you can hold the ignition switch on momentarily and the engine will run
let go of the switch it will stall do not do for long this runs 12 volts through ignition and will fry ignition.
Bob

Mine would run fine and seem like it just ran out of fuel when warmed up. I stalled out one time took, the spark arrestor and actually looked in the carb it was getting plenty of fuel. That's when I looked in my spare parts bag and found a pick up and reluctor this did cure the problem. I was very frustrating you would swear the engine was running out of fuel, I never expected to have electric problems. Like I said The spare parts made it easy to switch parts(having these spare parts on board came in handy) The only thing I didn't have on the boat was the fuel pump. Everything else came with the boat.
Bob

Repack with Teflon packing.

Jeff

PS: Easy for me to say it!