WOT no go!

[MikeyPa]

I have a 1989 Force outboard (85hp) with a weird problem.
When we take it to wide open throttle, she doesn't climb out of the
"Hole" for a long time, unless we pump the fuel bulb until she goes, then
everything is fine till we slow her down and attempt to go full bore again.

If we hook up an external electric fuel pump, the motor runs like it is supposed to.

We suspect a bad carb that may be losing fuel pressure around the
bowl and the extra pressure from the fuel pump overcomes the leak.

The question being asked is can the electric fuel pump harm the
engine over time?? Any comments on above thoughts also welcome.

Thanks.

MikeyPa

 

[rudedude]

Re: WOT no go!

Sounds like you just need to replace the fuel pump on your motor. The diaf. might be streched Like mine was. Got my parts here at iboats. Fast shipping and good price.

 

[Nate3172]

Re: WOT no go!

It definitely sounds like the fuel pump is the problem. I put an electric pump on my 85hp when my pump went out and have had no problems. The only thing to take into account is fuel pressure from the electric pump. Make sure it is one designed to feed a carburetor and not fuel injection for as the fuel injection pump will pump at way too high of a pressure for carburetors. Also insure that it is capable of delivering enough fuel so that it does not starve the engine. I got my pump at Napa and it was specifically designed for small gas engines and boats. It cost about $45.

 

[roadrunnr]

Re: WOT no go!

Nate:
Electric fuel pump! I never thought of going that route! Just curious, how did you install it? I'm guessing it's mounted on your powerhead somewhere, with power possibly coming from the terminal block on the portside. Post pictures if you can.

 

[Nate3172]

Re: WOT no go!

I will take some picks of it and post them as soon as I get a chance. It is actually mounted with the same screw that holds the plastic fuel filter housing to the pump.

 

[rogerwa]

Re: WOT no go!

http://www.iboats.com/mall/partfind...gd_poid=112435&gd_row=26&**********=018977543

Get this kit and apply it first. The carb bowls are not presurized. The pump pumps fuel into the bowl until the needle valve shuts it off. My guess is that you have a worn out or penetrated diaphram. Cheap and easy to start with.

You might also want to inspect you fuel lines for air leaks and that your carb floats are adjusted correctly.

 

[Nate3172]

Re: WOT no go!

You are correct about the bowls not being pressurised and that the needle shuts the fuel off. Too much pressure from a fuel pump will overcome the float and force itself past the needle. Which is why electric pumps for carburetors only produce 5-9 lbs of fuel pressure whereas fuel injected pumps produce upwards of 70-80 lbs.

 

[roscoe]

Re: WOT no go!

Rebuild the old fuel pump for $11, and clean and adjust the carbs, end of problem - with no fuel spill or fire hazard enhancement.

 

[MikDee]

Re: WOT no go!

Granted an electric fuel pump is good, but I think overkill on these motors when you can just get the replacement diaphram & parts easily, & cheaply, plus the electric pump is a fire hazard. Another thing is, you don't want to much pressure being pumped to the carbs.

 

[Nate3172]

Re: WOT no go!

An electric fuel pump is no more of a fire hazard than the mechanical. The main benefits to having one: Reliability over the mechanical, no more blown diaphrams starving your engine for fuel, no longer need a primer bulb. That's enough for me to justify spending the extra dough if I already have to fix or replace the mechanical pump anyway. Which I did and it works great- not a lick of problems.

 

[Frank Acampora]

Re: WOT no go!

I've often thought about installing an electric pump but never got a round tuit.

Couple of practical questions:

1. What is the current draw in amps? Can it be powered by the blue ignition wire so it goes on when the key is on and off when the key is off? (oops! forgot to mention that blue wire on distributor ignition is power to CD box--different than later Chrysler and Force engine ignition.)
2. How long does it take to prime the fuel line and carbs for the first start? (assuming they are empty or close to it?
3. What is the rated fuel delivery in gallons per hour at what pressure?

I'm thinking of replacing the twin pumps on my Chrysler 140 with one electric since even with two pumps it sometimes starves for fuel. And it's not bad pumps. At full throttle this baby performs and is HUNGRY. I forget--I think I have something like .096 or .098 jets in there but definitely larger than .092.

Thanks, Frank!

 

[Nate3172]

Re: WOT no go!

Frank, you can get just about whatever fuel rate you would want for an electric pump at Napa. They call them "pusher" pumps. They are small and square and generally do not require alot of power to run them. I use to buy them and put them on large diesal engines so they will definately have one that will deliver enough fuel for your outboard. Not sure what size fuel hose you are running but you may want to step up in size if you go to a higher gpm rate pump. The reason being is that a pump does not "create" pressure, only volume. Restriction creates the pressure. The more volume you try to force through a particular size oriface or hose, the pressure will increase. I kept the 1/4" hose because my engine hasn't been changed internally and I chose a pump that fed it what it needs and didn't go to a high gpm pump. As far as whether the blue wire you are talking about will handle the draw from the pump you choose I could not tell you. The pumps come with the specs. I ran an ignition source wire from my switch all the way back to where I mounted the pump. I just followed the controll cables al the way back to the engine and I used a shielded 2-wire cable (also available at Napa). It takes approx. 5-10 sec. to prime the system if the fuel is drained out of the carbs. Although, I think I'm going to wire the fuel pump through a toggle switch so that I can turn the pump off and run the fuel out of the carbs before pulling it out of the water at the launch. I get tired of having to clean the oily fuel residue out of the engine "bay" everytime I tilt the motor into the tow position. I'm kinda anal about cleanliness and like my boat and motor spotless. If you need any more help just give me a shout. My boat is stored for the winter already and I have been working out of state alot so I haven't been able to take pictures of the pump setup on my engine yet.

 

[Nate3172]

Re: WOT no go!

I should add one more benefit to having an electric pump on your outboard. There is a Napa almost everywhere. When my mechanical fuel pump went out I was in Idaho on my family vacation to do some fishing and water sports with the kids. It went bad the first day we put the boat in the water. No dealers anywhere close that would have the parts and if I ordered them they would have never made it in time. Went to the local Napa and the vacation was saved. That alone right there was totally worth the extra cost of going to an electric. I didn't have to hear from my wife and kids about how sucky the vacation was if I would have never got the boat running.

 

[MikDee]

Re: WOT no go!

I have one of these little square NAPA universal electric pumps laying around for about 20yrs,,, used it temporarily one time on an old I/O that was having fuel delivery problems. It's pretty nifty, and still in good shape, but I don't recall how much pressure it puts out, or if it can be adjusted? the directions are long gone.

 

[Nate3172]

Re: WOT no go!

Mikdee, the pump doesn't actually have a pressure rating because they do not create pressure. What they have is a gallons per minute (gpm) or gallons per hour (gph) rating. You can get a good idea of what the gpm is if you hook it up and have it pump into something that you can measure the amount of fuel it pumps in one minute.

 

[Nate3172]

Re: WOT no go!

Update on electric fuel pumps after doing research. It had been awhile when I installed mine and did not have any of the specs or anything on it anymore. What I have found out so far (I was wrong on this, sorry) is some of these universal fuel pumps DO have pressure ratings on them because they have internal pressure relief valves. Now, not all of these universal pumps have that, so the ones that do have the pressure rating. Good news for Frank, he would not have to worry about going to a higher volume pump and creating too much pressure for the relief valve in the pump will limit that. The brand of pump I installed is a Facet/Purolator and can be purchased at Napa, Pep Boys, and CarQuest. They have a number of differen't models to choose from with differen't gph and pressure ratings (for the ones internally relieved).

 

[QuadManiac]

Re: WOT no go!

Nate, when the pump ISN'T providing any flow the static pressure is the concern. When the float valves are closed, if the static pressure is too high, it can blow past valves. There IS no pressure drop across the system in this case because there is no flow. This static pressure is simply the work by the pump's impeller against the viscous friction of the fluid (gasoline) and it will be limited by the internal pressure relief valve (if it has one).

That said, I believe that the static pressure of most LOW pressure fuel pumps is not enough to be a problem. If it is, a fuel pressure regulator can be added at minimal cost. Holley has adjustable regulators for less than $30. I have one on my turbo VW powered sandrail and have to run the static pressure at around 3 psi, but in my case the fuel pressure is also vacuum regulated to provide more pressure, to overcome the losses due to additional flow, as the turbo's demand increases.

 

[Nate3172]

Re: WOT no go!

Exactly, which is why I recommend a low gph pump so the static pressure does not overcome the float itself and push past the needle. The one I installed has an internal relief of 4-5 psi. The gph is 35. This is more than enough to feed a 85hp and larger.
Since you brought up the turbo VW (which is very cool), I too had a turbo charged VW. I turbo charged my 77 rabbit. It got creamed by a Dodge pickup in a Home Depot parking lot believe it or not. After that I bought a 89 GTI and had a 2.0 litre that I was going to put in it with the turbo setup from the rabbit but the baby came along and never got around to it. I eventually bought a jetta glx with the vr6 and sold the gti to a friend with all the turbo stuff and the numerous goodies I had for the car. One of these days I'll probably pick-up another project car cause there are some things that I have since learned about turbo charging that I would love to try out.

 

[MikeyPa]

Re: WOT no go!

Checked with the owner of the boat (I sold it to him). He replaced the
fuel pump just in case that was problem, which of course didn't change
anything. He did ask what that "Nasty" decarb stuff was, and do you
have to remove the carbs to do it??
I think he plans on using the electric pump on a toggle switch to only
turn on when needed (it was bought at NAPA, some company in Ill makes
them).
Thanks the same for all information. I'll post THE fix if we ever locate
it. I think we are going up to winterize it in 2 weeks (300mRT).

MikeyPa

 

[eedwards]

Re: WOT no go!

The brand of pump I installed is a Facet/Purolator and can be purchased at Napa, Pep Boys, and CarQuest. They have a number of differen't models to choose from with differen't gph and pressure ratings (for the ones internally relieved).

Is it the small square one or the round ones?