1953 Evinrude 15 Hp 15012 - conversion to a fuel pump

[mark in new jersey]

Hey gang!

It's been a very long time since I've posted, so here's a brief catch-up: I got my engine running great! After three...yes, three... carb rebuilds, it turns out that the sintered fuel filter was completely blocked. New filter, and this runs really well.

If you remember my old posts (or, even if you don't!!), I converted this to a pump system, but as I struggled mightily to get this engine to run, I had to "step back" and remove any variables that I had entered into the equation. Thinking that my pump might have been the issue, I dismantled the pump, went back to a pressure tank, etc., etc. As stated, the issue was a bad filter, but I didn't know it then. All I knew was that I had air & spark.....the problem was clearly "fuel". So my troubleshooting required the removal of the pump & plumbing.

That said, I was never 100% happy with the pump I had installed. Someone had recommended...and I bought....a pump that, in retrospect, was way too big. It had a capacity to fuel a much larger engine than this little 15HP, the consequence of which was that it was hard to fit / mount under the cowling, harder still to plumb. I tossed it with no regrets.

Fast forward: I'm thinking about going back to a pump system, but I want the smallest possible pump for this engine, and I'm seeking specific recommendations. I've already tapped (1/8" NPT) the center hole in one of my bypass covers, so I'd like to obtain my "pulse" there. Mounting there would be great, too....if possible.

So: for those of you who have converted a 15012 (or an 013, 014, 015, etc.), what small pumps have you used successfully? I'm looking for specific make & model number....

Thanks much! And, it's good to be back! I'm going to begin building a boat of my own, and I can't wait to get this engine "back in the game"

Mark in New Jersey

 

[jbcurt00]

What pump did you use?

I know a lot of people that have done this mod
http://duckworksmagazine.com/05/columns/max/5/index.htm
But I dont know what pump# they used

And many of them have also added a excess fuel recovery tank to collect unburnt fuel from the exhaust to keep it out of their favorite waterways, even if only a little.

 

[mark in new jersey]

I don't remember the part number, although I'm sure it's in my records somewhere.

Here's a picture during the installation. I made a mounting plate that went over the upper bypass cover. That was the only way to fit it and still get the cowl on.

This thing was good for a 60HP motor....there's got to be a smaller pump, right?

 

[mark in new jersey]

I found this....Sierra #18-7350 http://www.iboats.com/Fuel-Pump-18-7...view_id.174139

I wish there were other pictures, as I'd like to see the backside.....how does it get its pulse? Could it possibly thread into the tapped hole in my bypass cover? (the center hole in the gasket leads me to believe "NO")

Anyone know?

 

[F_R]

The center hole mates with the hole in the bypass cover----IF you have the bypass cover designed for a fuel pump, which you don't

 

[F_R]

No Title

Bypass cover designed for a fuel pump looks something like #85 in this picture (1960 shown)

 

[mark in new jersey]

...IF you have the bypass cover designed for a fuel pump, which you don't

Gotcha.

When queried, my friend Google found for me the "rear view" that I wanted. I'm forced to wonder: Could I disassemble this pump, drill out & tap the hole in the aluminum backplate, then mount it directly to my (tapped) bypass cover with a 1/4" NPT close nipple?

Or am I WAY over-thinking this?

If there's a better, smaller, more-streamlined way, I'm all ears.

OR.......was there ever a pump-capable bypass cover made that would retrofit into my old engine?

 

[Woodonglass]

I think this one works too...https://www.denniskirk.com/mikuni/single-fuel-pump-df44-227.p1609.prd/1609.sku

 

[racerone]

Close nipple will work.---Note---- those wee pumps may have an arrow on them that says ----" up "

 

[HighTrim]

Well, your easiest option would be to get a 3 barb pump, then plumb a line from the barb you threaded into your bypass cover to the pulse barb. I have used these little guys many times for small hp motors.

http://www.ebay.com/itm/Mikuni-Fuel-...0AAOSwpDdVdUmD

Or, the other option would be to use a 2 barb fuel pump, like you have pictured. To accomplish that, simply make a custom plate, like what you did, to mount the pump to. Fill the void in the original bypass cover with JB Weld before the plate goes on. Then drill a hole straight through where the pulse hole is located on the back of the pump, then mount the pump to the plate with the supplied gasket. Done.

 

[pro-crastinator]

The Mikuni pump that Woodonglass showed us will be perfect for your application.
It will not keep up with a 30hp but your 15 is right in its wheelhouse.

MAybe $15-20 ? - if you scour the internet.

 

[HighTrim]

The Mikuni shown will pump 14 liters / hour, so a 30hp would be the upper end of its limit, if you ran around at WOT all the time. I find them bulky though for side mounting with a cowl, wont work well, if at all, especially since the pulse line comes out of it perpendicular to it. They do fit under the carb, but that leaves you with a less than desirable LONG pulse line.

Stick with the smaller briggs for 50s OMC cowls. Done many, trust me.

 

[HighTrim]

Here is one I have done.

 

[Crosbyman]

i have done mikuni...square pump over a aluminum plate and round B&S pump

high trim"s picture says it all nice clean job !!

drop me PM and I can send pics to your e-mail coordinates in a few days

 

[mark in new jersey]

Picture's worth a thousands words!

Mikuni (Briggs) pump is on order! $7 bucks, free shipping. eBay can be a wonderful thing!

Thanks to all!

 

[pro-crastinator]

No Title

High Trim is correct that the square mikuno has a problamatic fit. Here's mine.

 

[HighTrim]

Ah you looped the pulse line in towards the motor. Good idea.

 

[64osby]

Use a bypass cover from a junk motor on this one.

Mikuni under the carb on another.

Both work great.

 

[oldboat1]

If you go the route 64osby describes, be aware that the small square pumps differ slightly at the rear of the pump housing -- where it mounts to the bypass cover. One extends further: OEM 397839 or Sierra 18-7350 (fits an '83 9.9, among others). They are like the ones you pictured. The flatter version won't protrude as far, which may be desirable if there is a close fit under the hood. As I recall, the flat version was used on the early '70s 6hp, no doubt among many others.

But as you are already plumbed for it, would make sense to try out one of the Mikuni pumps. I don't know if the pumps have replacement diaphragms available -- might want to just buy two or three of the cheaper pumps. (square pump is about $70 for the OEM model; kits about $12.)

 

[mark in new jersey]

Use a bypass cover from a junk motor on this one.

This hits at the heart of the question I asked in post #7: Was there ever a bypass cover that a.) will directly fit my '53 Super Fastwin that is b.) configured for a directly-mounted pump? If so, anyone have an OMC part #?

If there is, I would like to go in that direction and will begin my search for such a cover.