4.3L Volvo stalls after hitting a wave

[DaveM]

I appologize if this gets long, but I am completely baffled and at the end of my rope.<br /><br />I have a 1994 Wellcraft Excel with only 100 hours on it that starts great and runs great. After running 10 - 20 minutes at around 3000 RPM it would sputter and stall after crossing a wake or a large wave. After that it then refused to start. I could start it the next day, no problem.<br /><br />I did the easy stuff: check that all cables were tight, replaced the fuel/water seperator, filled the tank with fresh gas. This problem was happening consistently as described, so I decided to winterize it and wait for the off season to bring it to a mechanic.<br /><br />Well guess what, I just took it in and the problem seems to have fixed itself. I took it out after the mechanic was unable to reproduce the problem and the boat ran perfectly at all speeds. Item checked include fuel pump pressure, anti-siphon valve, ignition coil heat, fuel and electrical connections. You guessed it, all is OK.<br /><br />Mechanic's conclusion: it sounds like a fuel starvation issue and may be temperature related. It could be vapor lock, except that would not explain why it stalled only after jouncing over a wave. He did find some water in the gas, but not enough to be concerned about. The aluminum anti-siphon valve could be replaced, but they are typically an "all or nothing" failure. It could be an electrical component that is on the edge of failure. In other words, he does not know.<br /><br />I need help!! My wife now does not trust the boat and refuses to be stranded again. And I'm afraid I'll drift into the Bill Gates compound and the SWAT team will be called in.<br /><br />-Clueless in Seattle

 

[Walter]

Re: 4.3L Volvo stalls after hitting a wave

About all I can suggest is to take it out and run it good and hard...bounce the heck out of it. Make sure you're prepared, though, in the event it does fail. Take along a cell phone (so you can warn Bill you're drifting ashore), or ask a fellow boater to go out with you so he can be there to assist with a tow if necessary.<br /><br />When you say your engine wouldn't start after it stalled and died...can I assume you mean it would crank over normally but just wouldn't fire...as if out of gas? Or would it not crank over at all...as if you're trying to start it in gear?<br /><br />Intermittent failures can be frustrating...not only for you but for your mechanic as well.<br /><br />Good luck!<br /><br />Walt

 

[DaveM]

Re: 4.3L Volvo stalls after hitting a wave

Thanks for the reply. You are correct that the motor will crank and crank 'til the cows come home (so to speak), but not fire. I cranked the throttle and I could see gas shoot through the carb.<br /><br />I thought it might be water in the gas, but it wouldn't that imply the motor would run rough the next time I started it? Instead, it purred like a kitten.<br /><br />-Perplexed

 

[Walter]

Re: 4.3L Volvo stalls after hitting a wave

If you can see gas getting to the carb, then it's not too likely a fuel starvation problem. I'm thinking something along the lines of ignition. But anything's possible!<br />Problem is...you won't be able to identify it and repair it until it fails again. It's possible your mechanic "fixed" it without knowing it. Poor electrical connections can drive you nuts... He may have moved a wire loom or fussed with a connector that was bad, thus restored the circuit.<br /><br />The fact that this problem occured when the boat is jounced tells me there is (was) a poor connection somewhere. You might consider running your engine on a garden hose in the driveway and CAREFULLY wiggle, tug on, pull on, manipulate your main ignition wire loom/connectors. (Be careful of shock...moving belts/pulleys etc)<br /><br />If I'm understanding correctly...the failure was fairly persistant but now it doesn't fail at all. There's only so much you can do to replicate the failure...and if your mech. inadvertantly fixed the problem...well, it may never fail again!<br />I realize this may not be too comforting for your wife, but that's just the way machines are at times.<br /><br />Once again...<br /><br />Good luck! Walt

 

[Walter]

Re: 4.3L Volvo stalls after hitting a wave

By the way...<br /><br />What power plant are we talking about here?

 

[Walter]

Re: 4.3L Volvo stalls after hitting a wave

Oh shoot...<br /><br />I just re-read your topic title.<br /><br />Duh!

 

[ODDD1]

Re: 4.3L Volvo stalls after hitting a wave

I think walter is headin in the right direction here.....dont forget about the wire harness under the dash...seen many that flop around and pull connections loose...good luck, intermittents are a real pain in the arse....

 

[DaveM]

Re: 4.3L Volvo stalls after hitting a wave

I agree that it sounds like an electrical problem. I did the hose thing and ran the boat in my driveway each time this problem reared its ugly head. I pulled, poked and prodded at any wire I could get my hands on. I focused on the under dash wires, especially the kill switch. All to no avail.<br /><br />It seems like if there was a loose cable this problem would eventually show up again. I spent 45 minutes cruising around trying to reproduce the problem the other day. I hit every wave in sight and flew wide open doing 43 mph! It worked great. I just don't think the problem fixed itself.<br /><br />-Befuddled

 

[Walter]

Re: 4.3L Volvo stalls after hitting a wave

Let's just assume the problem is in the ignition circuit. If this were my boat...I'd know how to "jump" the ignition circuit in the event it failed again. I'm not familiar with Volvo's circuits to tell you how you'd do that. However, it sounds like you have good mechanical/electrical understanding. I suggest you keep on board the proper tools/equipment (jumper wire, voltmeter, etc) and familiarize yourself with these circuits, so that if it fails again...you'll be prepared to troubleshoot the problem and get yourself back home again.<br /><br />The best of luck...<br /><br />Walt

 

[DaveM]

Re: 4.3L Volvo stalls after hitting a wave

Well, I used to think I had a reasonable understanding of how things worked. Now I'm feeling rather "more on" like, if you know what I mean.<br /><br />I think you are right that I'll need to load up with every diagnostic tool I own plus an extra gas can.<br /><br />Grrr, this is a most frustrating problem.

 

[Hooty]

Re: 4.3L Volvo stalls after hitting a wave

Cool Juan,<br />I'd think a jumper wire and squirt bottle of fuel would do the trick. 12v to + on the coil and a shot of fuel in tha card should tell the story. Maybe.<br /><br />g'luck & c/6<br /><br />Hooty

 

[SeaRay245]

Re: 4.3L Volvo stalls after hitting a wave

i think hooty is on the right track if it starts and runs this way u aleast know what your lookin for

 

[wyattm]

Re: 4.3L Volvo stalls after hitting a wave

Had a problem where boat ran great on the trailer and at slow speeds, when i hit the throttles to bring it up on plane the engine would die. After taking fuel tank out and replacing fuel twice and still have problem, we discovered the fuel line was being pinched by the rear jump seats, it was just enough pressure to cut fuel flow off when the bow came up and the aft end squatted down. Hope this helps.

 

[waterbuoy77]

Re: 4.3L Volvo stalls after hitting a wave

i know exacially what your problem is!!! It happened to me the same way , boat ran great and when i hit a wave it sputtered like crazy.. i did everything and it hit me one day i was shifting to get out of my dock .. i checked the (cut out switch) or interrupter switch on top of the engine,,, i hav a 4.3 as well.. its just a little black switch with a lever on it that rides in teeth that interrupt the motor when shifting into gear..i will almost guarentee that is what it is... it didnt do it while it was sitting and i even took the carb apart but to no avail...it was fixed when i bent the arm a little to get it to seat better... hope it helps...

 

[DaveM]

Re: 4.3L Volvo stalls after hitting a wave

What you describe is exactly what is happening to me. So where is this switch? I've scanned my Chilton's manual, but I can't seem to find any reference to this switch. I guarantee I'll rip the @#$% thing out once I find it!<br /><br />I'm liking Hooty's idea with a jumper and a squirt bottle of fuel. It seems devilishly simple.

 

[wyattm]

Re: 4.3L Volvo stalls after hitting a wave

The interrupt switch should be by the shifter connectors on top of the engine. It is a small black switch with little button that goes in as the cables are moved. It is there to keep the engine from shifting from Shifting into gear at high rpms. If the switch is bad it can be bypassed, but no recommend. This was an age old problem with 4.3 liter engines. Ususally the switch gets a bit of sand in it and makes the engine sound light a rod is coming thru the block. Good luck.

 

[Walter]

Re: 4.3L Volvo stalls after hitting a wave

I'd get nervous with raw fuel squirting around the place...yikes! But if that what it takes...just be sure your fire extinguisher is fully charged!<br /><br />It sounds like Waterbuoy 77 has hit the mark with what he describes with the shift cut-out switch. The one on my older Merc 898 model has never given me fits...but from what I understand of their purpose...I can see how one could give a fella grief. Go for it Juan, and maybe you won't have to resort to the spray bottle after all!<br /><br />By all means let us know how things turn out!<br /><br />Walt

 

[DaveM]

Re: 4.3L Volvo stalls after hitting a wave

Oh yea, nothing like a little engine fire to spoil a boating afternoon. It will be pretty easy to connect an auxiliary tank to the fuel filter inlet and that may be the prudent choice and a wise investment.<br /><br />I looked around by the shift cables, but did not see one and no reference in my manual. Someone mentioned they were on older Merc. engines, although I don't know how old is old. So even though it describes my experiences to a "T", I'm thinking my Volvo does not have a shift cut-out switch.<br /><br />I tell you what, party at my house once I get to the bottom of this one!