Time to rebuild the carb. on a 1957 7.5 hp

jbjennings

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Re: Time to rebuild the carb. on a 1957 7.5 hp

THis is how I've done it and it worked good. NOt that this is the proper way so do it at your own risk! I use a little propane torch to heat the area up and try putting a bind on it. I have also gotten a perfectly fitting screwdriver and used channel locks on the screwdriver to turn it with more torque. This could very well break the screw. I'd use the heat and the extra torque method carefully so you don't break the screw. I've also had half the screw head break off and that stinks. Heat heat heat. It should work. Don't set yourself on fire!:) Remember where the gas can is!
Good luck,
JBJ​
 

Tim Frank

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Re: Time to rebuild the carb. on a 1957 7.5 hp

that you drop in the cylindrical orifice and tap on it in order to flatten it out and seal it in there. Some folks like to use a dab of epoxy to be sure it doesn't leak, although I've never tried it or had a problem with no epoxy.
Good luck,
JBJ

As a slightly easier alternative (no mixing, no waste) to epoxy, I borrow some nail polish from my daughter and just put a small bead all around the perimeter. Comes with a built-in applicator and some really wild colours...:)
 

BSDenning

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Re: Time to rebuild the carb. on a 1957 7.5 hp

OK, I got the screws out. I borrowed a screwdriver that fit the screw better than mine did and I used a channel lock to get more tourque.

I've taken everything apart and I replaced the impeller. I'm waiting on my gaskets and stuff to get here before I put it all back together. My friend that I borrowed the screwdriver from said I should use some marine gasket sealer on the lower unit when I put it back on and around the powerhead gasket when I put it back on. Is that what I need?
 

jbjennings

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Re: Time to rebuild the carb. on a 1957 7.5 hp

Myself, I don't use gasket sealer on the lower unit when I bolt it back on, and I don't use gasket sealer on the powerhead gasket. I also trace out my powerhead gaskets out of felpro black gasket from the auto parts store.....cheaper and I hate to wait to put it all back---yes, I'm totally impatient!:D I like a single-hole paper punch to punch out the bolt holes in gaskets.
later,
JBJ
 

BSDenning

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Re: Time to rebuild the carb. on a 1957 7.5 hp

My motor didn't have a gasket on the powerhead. It looks like whoever did this job last time just put gasket sealer around it and bolted it back on. I've already ordered the gasket, so I'll wait for it and use it.

When I pulled the lower unit off, a spring and a few washers fell out. I'm not sure exactly where they went. I think they were on the drive shaft. I'll have to look at my parts manual and see if I can figure out exactly where they went.:confused:
 

jbjennings

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Re: Time to rebuild the carb. on a 1957 7.5 hp

That was the lower crankshaft carbon seal. VERY important. I'll see if I can find one of F-R's old posts to show the correct sequence. He recommends replacing that carbon seal every time because if it leaks it can let water in and ruin the motor.
I'll look,
JBJ
 

jbjennings

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Re: Time to rebuild the carb. on a 1957 7.5 hp

Part # for carbon seal o-ring is 303347. My parts manual is on my 'puter at work so I don't have a pic of the assembly handy. I got that part # from one of F-R's old posts. Can't find a pic of the assembly for the carbon seal but if noone checks in, I'll post it tomorrow morning before work.
Later,
JBJ
 

BSDenning

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Re: Time to rebuild the carb. on a 1957 7.5 hp

The fuel filter is located in the glass bowl on the bottom of the carb. You should also change the cork gasket and o-ring that sit on top of the driveshaft when you do the impeller. They make up the lower crankcase seal.

I emailed the guy at http://www.laingsoutboards.com/ and I requested the cork gasket and o-ring that sit on top of the driveshaft for when I replace the impeller and the guy emailed me and said he would be add it to my order with the float. So, I am assuming that is the part number 303347 (Lower bearing seal to drive shaft "O" ring) was the part that I requested.

Is this what you were refurring to?
 

BSDenning

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Re: Time to rebuild the carb. on a 1957 7.5 hp

I've got some leftover parts from the carburator rebuild kit. Here are all the leftover parts:


100_1774.jpg



I'm not too concerned with the large gaskets, because I'm sure they don't fit my motor. The screw holes don't line up right.


100_1779.jpg



I am more concerned with these parts. I didn't see anything in my carburator that looked like those 2 metal pieces or the 2 rubber O rings. My kit came with 7 of those little red washers. I used 2 of them as packing for the high and low speed needles. I wonder if those rubber O rings were supposed to be used as packing...:confused:

Any ideas?
 

BSDenning

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Re: Time to rebuild the carb. on a 1957 7.5 hp

Another Question:

My parts manual shows one Carburator to manifold gasket. According to http://outboard-boat-motor-repair.c...hnson 5.5 HP 1954-1964 Carburetor Tune-UP.htm , I am supposed to use 2 gaskets in order to protect the carburator from the heat of the motor. Is this true? If so, what order should I put the gaskets on the motor, smaller one closer to the carburater and larger one closer to the crankcase, or the other way around? Here are some pictures:

100_1804.jpg

(the old gasket is on the left and the new ones are on the right)


100_1801.jpg


100_1802.jpg
 

coolguy147

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Re: Time to rebuild the carb. on a 1957 7.5 hp

the gaskets dont help to stop it from heating up the carb. it just seals it to the reed cover so it will not leak alll ovr try running it without the gasket.
u know i noticed that it condesenses around that area because of the pressurized fuel system. use the gasket lol
 

Sea18Horse

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Re: Time to rebuild the carb. on a 1957 7.5 hp

Yeah, I agree with cg. Just use the one that matches up with your old one the best. The others are used for other engines. The same kit is used for a lot of other sizes. 5.5 7.5 10 15 18.

Cheers.................Todd
 

wbeaton

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Re: Time to rebuild the carb. on a 1957 7.5 hp

I've attached a photo of the parts that make up the lower crankcase seal that sits on top of the driveshaft. You need to replace the cork gasket (#1 in the photo) and the o-ring (#3).

cork gasket = BRP 303355 or Sierra 18-2892
0-ring = BRP 303347 or Sierra 18-7180

You only need one carb to intake gasket. The carb rebuild kit is a mulit-year kit so it has lots of extra parts you don't need. Keep them anyway especially the packing. You may use it again on another motor in the future.
 

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  • Lower crankcase seal.JPG
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BSDenning

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Re: Time to rebuild the carb. on a 1957 7.5 hp

OK, that sounds good. I won't worry about those left over parts then.

I recieved my new float and gaskets in the mail. I should be installing them tomorrow night. I'll let you know how it goes. Thanks for all the help everyone. :D

P.S. I'll probably be doing all this same work to my 1962 10hp Evinrude Sportwin some time soon. So, you may see some posts about that in the future. :)
 

BSDenning

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Re: Time to rebuild the carb. on a 1957 7.5 hp

I just opened the box that I got in the mail from http://www.laingsoutboards.com/newpage4.htm and I was supprised to see that my new float was not made of black plastic. It actually looks like another cork float. I ordered it off the "new parts" page, so I hope it is new. I don't want to replace my old float with another old float... Here is a picture of my new float:

100_1810.jpg


I thought that I would get a black plastic float like the one pictured on this webpage: http://outboard-boat-motor-repair.c...hnson 5.5 HP 1954-1964 Carburetor Tune-UP.htm

Any thoughts on this?

It would cost me $4.80 to mail this back to the Laing's Outboards, so I guess I'll go ahead and install it and then the next time I rebuild the carburator, I will see if I can get a plastic float. Where can I get one? :mad:
 

coolguy147

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Re: Time to rebuild the carb. on a 1957 7.5 hp

i suggest just going to the dealer and getting the real thing if that cork one isnt the right one lol
 

BSDenning

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Re: Time to rebuild the carb. on a 1957 7.5 hp

I went ahead and installed the cork float and put everything back together. I tested it out in a trashcan today and it ran very well. I'm going to test it in the river and set the carburator on Friday.

Does anyone know where I can get those new black plastic floats? I will probably be working on my 1962 10hp soon, and if needed, I'd like to get a float that won't disentigrate.
 

jbjennings

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Re: Time to rebuild the carb. on a 1957 7.5 hp

Myself,
I wouldn't worry that the new float is cork. It should last just fine. I'm almost positive that the plastic float for a '57 or '58 18hp will fit it perfect. Let me double check--will try to do that later.
Glad you got it fixed,
JBJ​
 

BSDenning

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Re: Time to rebuild the carb. on a 1957 7.5 hp

I ran my motor on the river today. It ran very well once I got the carburator adjusted right. The powerhead was leaking water from where it sits on the lower unit, but I think it's just because I didn't have the screws tight enough. I tighenend them and it seemed to stop leaking. there seems to also be a leak around the gear shifter handle. It was doing that before I did any of this work on it. It just drips a little. Is it possible to fix that and should I be worried about fixing it?
 
D

DJ

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Re: Time to rebuild the carb. on a 1957 7.5 hp

I ran my motor on the river today. It ran very well once I got the carburator adjusted right. The powerhead was leaking water from where it sits on the lower unit, but I think it's just because I didn't have the screws tight enough. I tighenend them and it seemed to stop leaking. there seems to also be a leak around the gear shifter handle. It was doing that before I did any of this work on it. It just drips a little. Is it possible to fix that and should I be worried about fixing it?

That shift shaft gets worn from use and vibration.

Guess what? You have to take the powerhead back off to get to it.:eek:
 
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