My boat had mechanical fuel pump and choke on it prior to this build. New motor has electric fuel pump and choke. Where should I tap my hot lead? As far as I know, the only wire in the engine compartment that is hot only with ignition on is the coil wire, but isn't it a "no no" to draw much current from here? Do I need to run a wire from here to trigger relays for the pump and choke coil?

Thanks!

That lead can carry the choke no problem but only for a trigger for a relay to carry the fuel pump.

That's kind of what I thought. I'm a little surprised that the heating coil for the choke doesn't need a relay too.

I'm thinking about adding an oil pressure safety switch to the fuel pump circuit as well. Along with this, I would like to have a way to override the safety switch when the engine is being started. I thought about taking a lead from the starter solenoid to provide bypass power to the fuel pump relay, but wouldn't this require a one-way diode or something similar to prevent current from running backwards to the starter solenoid?

hey budman,

since your doing very similiar stuff to your boat that i am can you tell me what you used for a throttle cable bracket on your new carb??? i got a holley i'm putting on mine on a air gap intake and the old bracket from my Q jet wont fit so i can attach the throttle cable...

as for your choke hot lead, everytihng i read says not to use that ignition lead for the choke heat coil... i assume theres hot going to the trim pump whenever the key is on, but i dont know if it will draw to much and pop a fuse....

good luck!

Hmmm, had not thought about the trim pump, gsxr - good idea.

I am in the very same process of working out my throttle bracket. I have the exact same issue. I bought one of the plates that go under the carb from an OSO member - they look like this:

http://www.summitracing.com/parts/SUM-G1419/

That is the best price I found on the net. But then you need something like this:

http://www.cpperformance.com/p-14094...rsion-kit.aspx

Personally, I thought $34 is a little steep for an itty bitty bracket like that. I am going to try to fabricate one out of angle iron using the existing shouldered bolt from the Q-jet bracket.

However, I am also having an issue with the Holley cab throttle having more travel than my Morse throttle cable can provide. Still scratching my head over that one. Isn't piecing a boat together fun?

i saw that bracket and wondered how it would work! i agrere that bracket kit with the L bracket is pricey for what you get, my problem is at this point i just want to get it done and on the water ASAP!!

which hole are you using on the holley linkage, if your using the big hole that might be why you have more travel since its farther from the pivot point??? are you using the hole i circled in red or in black???

i was hoping not to hear that the OEM cable doesnt fit right even with all these adapter brackets, i dont need to engineer more fixs.......

I have not really decided which hole to use. The large one seemed logical, but I agree that the smaller one requires less travel by virtue of being closer to the pivot point. I need to get someone else in the boat to work the throttle for my while I observe the cable travel alongside the throttle lever travel.

What's the fitting circled in blue?

The trim pump is connected direct to battery power, not ignition power.

The ignition feed will be adequate to carry the choke coil. Not really an issue but if it concerns you,your best bet is to use a pair of relays. You can make a set of power tap leads and attach them to the battery terminal of the alternator with an inline ATO type sealed fuse holder inline to protect the relay fed circuit. Use the IGN terminal at the coil to to trigger the relays.

If you want a no oil pressure safety shut down on the fuel pump, use an oil pressure switch, closed with zero pressure, open when there is oil pressure and put it inline with the ground terminal on the activation circuit of a second fuel pump relay. Wire that relay to the same power feeds, grounded through the O/P switch BUT, use the #30 and #87a terminals for the power line to the other fuel pump relay. Those two terminals are connected when the relay is NOT energised. Power just goes in and back out. No oil pressure = instant ground for the relay = energised relay = no more electrical contact between #30 and #87a = fuel pump shut down.

There should be sufficient fuel in the bowls to start the motor. Oil pressure will build quickly enough while cranking to trigger the pump anyways and if the boat has been sitting for a while, a little extended crank time before firing is not a bad thing.

On your throttle issue, use the lower hole in the throttle lever, not the big one . If you measure and cut carefully, you can modify the Q Jet bracket to attach with one carb hold down bolt and rest against the carb body for support. You can then drill and tap the base plate and the throttle bracket beside the main hold down bolt and bolt the bracket to the carb.
Plenty strong that way.

Your electric fuel pump needs to be off a relay from the ignition, which is also in series with your tether switch. So if you leave the boat for any reason the fuel pumps also shut down. (it is not a bad idea to tie all that in with a low oil pressure switch)

Yeah.......what Airpacker said.