fuel pump conversion

JB

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Re: fuel pump conversion

Well, that procedure would work, jdsgrog, but it is a lot more trouble than this one: http://forums.iboats.com/showthread.php?t=205628

Your 10Hp can do it just like tashasdaddy did his 35HP, and TD and F_R are right here to help you with any questions you may have.
 

jdsgrog

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Re: fuel pump conversion

Thanks for the reply and yes, I did see that, but from what I saw, my bypass covers do not have the fittings as on the 35 or 18. I saw on the net a tutorial by Paul Moir that would work for my motor in which he created a plate, but it seems to be quite a project. The web page is:

http://www.shareaproject.com/pages/projectTut,p,408,00.html

I also saw one from flyboy712 on that thread you gave that seemed simple enough, but I am wondering if the curved interior on my motor's bypass cover would affect the fitting and vacuum created for the pump. Theoretically it seems like it would work, but practically, I wonder. Any thoughts would help.
 

F_R

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Re: fuel pump conversion

Thousands (millions) of motors have been built, mounting the fuel pump on the bypass cover. That's the way it's been done forever. The curve has nothing to do with it.

Another approach is to use a fuel pump such was suggested in the first article but instead of tearing into the intake manifold like that simply drill and tap a hole in the bypass cover for a hose nipple. Then connect the fuel pump to the nipple with a piece of hose. That would be a WHOLE LOT easier.
 

jdsgrog

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Re: fuel pump conversion

Thanks. I'll drill the hole in the bypass cover and get a hose nipple.
 

samo_ott

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Re: fuel pump conversion

Doesn't the later 10's have a bypass cover that will bolt on the earlier ones? I forget now on all my 10's.

Also, if drilling the hole, put a blob of grease on your drill it so that the filings do not fall in and also if you drill upwards it will help even more.
 

jay_merrill

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Re: fuel pump conversion

Remember, also, that the procedure detailed in the first link here is specifically for the 5.5hp, which doesn't have bypass covers.
 

jdsgrog

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Re: fuel pump conversion

Oh, didn't realize the 5's didn't have bypass covers. As for the bypass cover on my motor, I'll be taking it off the motor and using a drill press and then tapping it. From the FAQ thread, flyboy712 said that he used a 1/8" NPT tap. I'm assuming this would work for my motor. If I'm mistaken, please let me know. Thanks, you guys are all a great help.
 

tashasdaddy

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Re: fuel pump conversion

here is the picture referenced above by F_R. looks like a good way to do it.
 

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burroak

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Re: fuel pump conversion

This is not the same size motor but it will work just as well; and it is a sanitary bit of work. I don't know exactly what your by-pass cover plate looks like but all of these can be adapted with a small drill press and tap.
http://i12.ebayimg.com/05/i/000/d4/24/1c70_1.JPG
 

jdsgrog

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Re: fuel pump conversion

Thanks, all, for the pictures. The bypass cover on my motor seems to best resemble the one F_R and tashasdaddy posted. I'm going to go out to where my boat and motor is stored and take a look. From what I saw, it seemed easy enough to take off the motor.

A couple of other questions, what size barb/nipple and hose is used? Also, what size drill bit would I need to use?
 

F_R

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Re: fuel pump conversion

If anyone wants to get real picky about it, a 18" NPT tap (tapered pipe thread) uses a letter "R" drill bit. Not being so picky about it, a 21/64' drill will work just fine. Select nipple/hose size to match whatever the fuel pump that you decide on has.
 

jdsgrog

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Re: fuel pump conversion

I just got back from the storage, and I pulled the bypass cover. Below is a picture. It is about 2" at its widest and 3" at its longest (the picture shows the cover on its side). One concern I have, the metal housing where I would drill is actually pretty thin. I'm thinking it's about 1/8" thick. Would there be enough threads to hold the nipple in place?

One other thing, I found that there is no spark in either cylinder. I tried pulling the flywheel, but it seems a bit stubborn and is not coming off. I did remove the nut, but am I missing something? Please advise.

IMAGE_019.jpg
 

F_R

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Re: fuel pump conversion

It is thick enough. Put a drop of Locktite on the threads before you insert the fitting. It will seal it up very nicely.

Those motors are notorious for having bad coils. You need a puller to get the flywheel off. I'll bet tashasdaddy will be along soon to post a picture.
 

jdsgrog

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Re: fuel pump conversion

I tried a puller that I have. Though it's not an omc puller, it pulled off the flywheel of my other motor (johnson 33hp). But this flywheel on this 10hp is on really tight. Is there any way to loosen it?

Also, is there a way to keep the flywheel from turning? On my johnson 33hp, the flywheel had teeth and I was able to jam a screwdriver between the teeth of the flywheel and the starter, but this one doesn't have teeth so there 's no way of jamming it.
 

burroak

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Re: fuel pump conversion

One concern I have, the metal housing where I would drill is actually pretty thin. I'm thinking it's about 1/8" thick. Would there be enough threads to hold the nipple in place?
It will be enough, but if you want some more assurance, screw the nipple flush into the by pass plate and run a thin profile nut down to snug up the nipple and the cover plate. Use the lock tite as suggested.
 
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