I did #27 on my lift and although there a lot of steps, not that big of a deal. Mine were amazingly brown and slightly clogged. VST drained clear and bright fuel.
2003 era 330 Anti-Siphon Valve?
- Thread starter Bayhouse
- Start date
Not trying to hijack your thread. Im having same issue with my Marlin 300 running main tank both motors stall at cruising speed primer balls are squishy. If I pump them some times it will start rite up. I run one engine on main tank and other on auxiliary tank and the engine on main tank stalled out so from what im thinking its my main tank From tank to water separator. I did replace fuel caps with new vented. I ran boat 75 miles all felt good no stalling. Have you tried replacing Anti feed valves and fuel line? I have ordered new valves and going to replace fuel line and primer balls.
No derail at all, more of an add to the conversation.
Replacing the fuel lines is on my list to-do and I'm probably going to do the bulbs too, even though they're only ~2 years old. By Anti Feed valves, do you mean anti-siphon?
Replacing the fuel lines is on my list to-do and I'm probably going to do the bulbs too, even though they're only ~2 years old. By Anti Feed valves, do you mean anti-siphon?
It would be helpful to know what would happen if you swapped tank feeds so that the motor that was on main now runs of aux and visa-versa.
I did that by fuel tank switch valve on port and starboard engines and it always showed main tank. Never stalled on aux tank. My parts should be here today I will keep you informed on what I find.
Cool. Question, is your problem intermittent or can you recreate it? Are you going to replace everything and then test or do it in phases? Seems like the Anti-siphon valve would be easiest to replace first.
It an intermittent problem. While the boats out of the water im gonna do Anti-siphon valves, fuel lines and new OEM primer balls.
Another update, but still not solved, just some new observations.
Boat sat at the dock for a few days while the wind blew crazy. First day after, had a major engine stall issue, probably 10-12 times right after we got started and were putting around - affected alternating engines. Next day on the putt out, only 1 stall. Next 2 trips, not a single problem. Last trip, after running ~4hrs and trolling, one engine stalled.
I've also noticed that the stalls are often accompanied by the RPMs on the engine about to stall revving higher, then rapidly dropping.
It's those days of no-stalling after a lot of use that is making me think this is not gas supply related....
Boat sat at the dock for a few days while the wind blew crazy. First day after, had a major engine stall issue, probably 10-12 times right after we got started and were putting around - affected alternating engines. Next day on the putt out, only 1 stall. Next 2 trips, not a single problem. Last trip, after running ~4hrs and trolling, one engine stalled.
I've also noticed that the stalls are often accompanied by the RPMs on the engine about to stall revving higher, then rapidly dropping.
It's those days of no-stalling after a lot of use that is making me think this is not gas supply related....
OK... RPM's going higher just before stalling is typically indicative of lack of fuel supply.
-- Can this happen to either engine?
-- What happens to the primer bulb?
We probably talked about this already, but if it's a fuel supply issue, it can be... the tank pickup... AS valve... the fuel lines, themselves failing internally... primer bulb... among other things. That's why running on a portable tank works so well - granted, you'll need to carry some jerry cans with you - or siphon fuel out of the onboard tank.
-- Can this happen to either engine?
-- What happens to the primer bulb?
We probably talked about this already, but if it's a fuel supply issue, it can be... the tank pickup... AS valve... the fuel lines, themselves failing internally... primer bulb... among other things. That's why running on a portable tank works so well - granted, you'll need to carry some jerry cans with you - or siphon fuel out of the onboard tank.
Happens to both engines, sometimes together, sometimes individually.
Primer bulb is always squishy, never flat.
I was thinking the fuel lines or ASV, but would have thought it'd be a little more consistent regardless of usage.
I'm not saying this IS the issue, but it could certainly be explained by a fuel line that is failing internally. Especially with ethanol - and if those fuel lines are 17 years old. What can happen is they start to come apart a bit on the inside and the "flap" acts as a check valve - sometimes stopping fuel, sometimes not.
If you can replicate at the dock, get a fuel pressure gauge, attach it and see what the pressure does when the motor acts up. You can do that at sea also but it is a bit of a pain since the cowling has to be removed.
The most common suggestion to these kinds of issues is to use a portable fuel tank plumbed right to the motor, basically bypassing as much of the fuel delivery system as possible. You can do that for one motor. If the problem does not occur, move the connection back so that more of the components, like bulbs and filters are included. If you get all the way back to the tank including the original fuel line,and the problem doesn't occur, the issue is in the tank.
One thing I don't think I mentioned is that sometimes there is junk in the tank that gets sucked up against the pickups and blocks fuel flow. When you stall, the gunk drops back to the bottom of the tank and the motor starts up. I am not saying that is your problem but at some point it may have to be tested.
The most common suggestion to these kinds of issues is to use a portable fuel tank plumbed right to the motor, basically bypassing as much of the fuel delivery system as possible. You can do that for one motor. If the problem does not occur, move the connection back so that more of the components, like bulbs and filters are included. If you get all the way back to the tank including the original fuel line,and the problem doesn't occur, the issue is in the tank.
One thing I don't think I mentioned is that sometimes there is junk in the tank that gets sucked up against the pickups and blocks fuel flow. When you stall, the gunk drops back to the bottom of the tank and the motor starts up. I am not saying that is your problem but at some point it may have to be tested.
I'd change the VST filters and rule those out. Fixed my intermittent problem and they looked bad even though the drained fuel from the VST looked great..
There is I believe a screen on the fuel pressure regulator than has been known to get clogged up. Again, a fuel rail pressure test would show a problem
SkunkBoat
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he's got suzukis...I don't think he has that screen.
I'm the kind of guy that hates to give in... so I would definitely do things like change every filter, all ASVs (I'd put in straight hose barbs), new hoses. After that, remove and send out the fuel injectors for cleaning.
I'd do all that because it probably needs it anyways...
If none of that works, get the Suzuki dealer to hook up the computer and tell you what he thinks...
...or just do that now....
As in not a whole lot of fuel in it? Running out of fuel in the line wouldn't cause it to collapse - a vacuum would (a clog downstream of the bulb would).