SoCal Jet Boats
Tech Talk => Engine Mechanical / Electrical => Topic started by: avengerdaycruiser on July 05, 2011, 09:53:18 PM
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Took the boat out with the new goodies and it ran great especially with the new carb. My problem is the Holley electric fuel pump was running fine then when running across the lake it just dies and the fuel pump shuts off. I turned the ignition back on and nothing from the fuel pump. So I waited a few minutes and tried again and fired right up. about five minutes later the same thing, let it sit and then it will come back on after cycling the key a couple times. Could it just be getting hot, it is hot to the touch not enough to burn you though. It is bolted on the stringer next to the motor mount, could it be too close to a heat source and just shutting itself off. The pump is new and a new filter and all new lines.
One other question...I just realized my transom housing on my jet that was installed here locally hangs below the bottom of the hull about 3/4" on each corner on the bottom. That has to be creating alot of drag and affecting my top end especially. Not sure how much it would increase if I fix it but could I just cut off the excess and smooth it out to match the line of the hull?
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mine is mounted to my stringer underneath my exhaust manifold... no problems here in havasu 120* heat. perhaps its just a loose connection inside when it gets hot? how old is it? perhaps try contacting holley about warranty/replacement?
you can see mine next to all the sawdust and metal shavings. heh.
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Took the boat out with the new goodies and it ran great especially with the new carb. My problem is the Holley electric fuel pump was running fine then when running across the lake it just dies and the fuel pump shuts off. I turned the ignition back on and nothing from the fuel pump. So I waited a few minutes and tried again and fired right up. about five minutes later the same thing, let it sit and then it will come back on after cycling the key a couple times. Could it just be getting hot, it is hot to the touch not enough to burn you though. It is bolted on the stringer next to the motor mount, could it be too close to a heat source and just shutting itself off. The pump is new and a new filter and all new lines.
One other question...I just realized my transom housing on my jet that was installed here locally hangs below the bottom of the hull about 3/4" on each corner on the bottom. That has to be creating alot of drag and affecting my top end especially. Not sure how much it would increase if I fix it but could I just cut off the excess and smooth it out to match the line of the hull?
First, you really shouldn't be running a "Red" on a boat. BUT, that being said, is it running through a relay that may be failing? Possibly the ignition switch itself? COULD be a bad pump. Everything else OK on the engine? I mean Oil Pressure, etc? Not uncommon to see them wired through an oil pressure switch. I'd be leaning towards it being wired through a relay that's going bad, or as you suggested, I doubt the thermal inside it is cutting out, Mine is mounted on the fuel pump blockoff and never had an issue with it.
On the Transom adaptor, yeah, cut it off. Personally, I'd mark it and remove it then do it, but if you have a steady hand, have at it. The transom adaptor is really only even there to keep water out of the boat. There's really nothing structural about it. ;)
Ray
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No it isn't wired into a relay just off a ignition wire in my wire harness and i dont have a fuse to it though I probably should put one on. It is just grounded to the block. but the pump is brand new unless it is faulty, oil pressure was great. And I have mine installed in the exact same position as Ka0tyk's pump.
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I don't think heats the problem. POssibly a ground? or the ignition switch itself. Sometimes there's a LOT run directly off the ignition switch without relays that can cause issues. First hand experience with THAT!
Ray
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I run a mechanical with a electric to cover situations just like this
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Okay I will try a better ground and possibly wire it directly to the battery with just a switch amd see how she does
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Do yourself a favor and wire it through a relay
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WIRE IT THRU A RELAY!!!
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The red will work to a much higher HP in a boat than a car. Tanks next to motor, not pushing against the G forces on launch, much less heat soak than a car, etc. Never been stuck by a mechanical pump, but have been walking/ swimming 5 or 6 times with an electric in the last 35+ years. I run a Blue at 785 HP with no issues, but until I replace it with a mechanical and reinvent all of my brackets(its an I/O deal), I carry a new spare with the A/N fittings installed and a plug-in wiring deal. When the last electric pump failed last season, it cost me a ride up on the rocks from the wind, 12 hours of bottom work, and a prop rebuild. I also carry a spare regulator, also with fittings, the Hi-vol mechanical is a better deal, no regulator either. Your results may vary. TIMINATOR
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what kind of relay do I use and any ideas where to pick one up at? and what is the purpose of the relay? Just curious on what it does
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what kind of relay do I use and any ideas where to pick one up at? and what is the purpose of the relay? Just curious on what it does
When you wire up a fuel pump thru a relay what you are doing is running the pump on it's own dedicated circuit. It's never a good idea to run something like a fuel pump on the same circuit as something else because you run the risk of overloading that circuit. I imagine that is what's goin on with you boat. You're probably overheating the ignition switch in your boat and that's why the boat runs for a few minutes after things cool down. Summit racing and Jegs carry electric fuel pump relay kits. I'm sure that ka0tyk has his wired up thru a relay and he's really good at posting diagrams and stuff. If you're nice to him, I'm sure he'd be glad to help :)
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Okay I think I understood that I will get a relay on this thing and move the pump away from the stringer because of the exhaust just in case thats a problem too. Thanks All! wish me luck
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When you wire up a fuel pump thru a relay what you are doing is running the pump on it's own dedicated circuit. It's never a good idea to run something like a fuel pump on the same circuit as something else because you run the risk of overloading that circuit. I imagine that is what's goin on with you boat. You're probably overheating the ignition switch in your boat and that's why the boat runs for a few minutes after things cool down. Summit racing and Jegs carry electric fuel pump relay kits. I'm sure that ka0tyk has his wired up thru a relay and he's really good at posting diagrams and stuff. If you're nice to him, I'm sure he'd be glad to help :)
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Most autoparts stores carry the little black relays and plug-in wiring harnesses too. Both are about $16/$17 together. They are used for high powered off road lighting, electric fans, and the like. Buy a spare relay too, they are not corrosion proof. TIMINATOR