crazy upgrade idea

[czuniga]

Is these where the shims go

 

[Johny25]

Yes, right under the leaf stops and on top of the valves. So in between them.

 

[czuniga]

So I remove those flaps and install them underneath

 

[czuniga]

Great pic. Hopefully this thread can help someone else in the future. I think I get it. I removed these two screws and install the shims right under them. Question I would just be raising the leafs a little bit. How would this improve performance

 

[Johny25]

Your raising the leaf stops and not the leaf valves. With the stop leafs being higher up it allows the valves to open up further. Essentially they will bend open farther. Make sure you get them back on correctly. Do one side at a time so you can always reference to the other side and so you put the same leaf stop back in the same spot. The leaf valve is also referenced to as "the reeds" and it is just a very thin piece of metal that opens and closes to allow air and fuel to the crankcase.

Do not put them under the leaf valves! Just so we are clear put them on top of the leaf valves (thin metal flapper) and underneath the leaf stops (the thicker metal stops that do not bend or flap). I hope this clears up your question : )

 

[Pappy]

Johny25 - I will gladly defer to you on the exhaust. I looked at one this afternoon (mid -80s) and the dam does not go all the way to the top as I thought it did so there may very well be a difference in noise level although I have never noticed it. Good job!
On the reed screws.... make sure loctite is used on re-assembly. This was already mentioned in an earlier post. Also make sure the water tube grommet or grommets are replaced during the changeover. Cheap and needed.

 

[czuniga]

Anyone happen to know if I would need to replace any gaskets for the leaf plate. If been trying to oder the head to exhaust housing. And the water tube gourmets. But iboats can't seem yo find what I'm talking about.my shimssand carb should be on the way. Missing the megaphone. Can't seem to find one. Just want to get all the small parts in. Anyone happen to have part numbers.

Thanks

 

[Johny25]

Yes replace both gaskets, one on each side of the leaf (reed) plate. Also replace the gasket between the carb and intake manifold. What parts are you needing numbers for? Please be specific

 

[czuniga]

The part numbers for these gaskets and the gasket for the power head to exhaust. Thanks

 

[Johny25]

Exhaust to powerhead gasket #0325721
Intake manifold gasket #0325260
Reed plate to crankase gasket #0318924

And get a carb rebuild kit for your new carburetor #0398453

All these parts can be looked up on this site https://www.marineengine.com/parts/johnson-evinrude-parts.php?year=1980&hp=15&model=J15RCSD&manufacturer=Johnson&section=Carburetor+%26amp%3B+Manifold

boats.net usually is the best for prices that I know of but if you don't live near Florida then it takes forever for the parts to get to you. I only buy from boats.net when I am not in a hurry for parts. I didn't have time ti look the water tube grommet up but you can do that I am sure :lol:

DO NOT BUY SIERRA GASKETS OR PARTS! GET OEM ALWAYS!

 

[czuniga]

Is this the exhaust I need to purchase. Just want to know. For some reason Ihought it was completely round

 

[Johny25]

No that is not the exhaust you want. The one you want is round on one end. That link I gave you earlier in this thread shows exactly what you need. The exhaust on the right is the one your looking for.

 

[czuniga]

Thanks I appreciate it.

 

[czuniga]

Question,,
once i get the shorter exhaust i replace the water tube from my old exhaust right. Does the water tube need to connect from the top all the way to the bottom?

thanks

 

[Johny25]

You can use the water tube off the one you remove. It should fit just fine. Yes it needs to connect to your impeller housing in the lower unit and also at the top in the exhaust grommet or else you will have no water flow, with no water flow engine will overheat a seize. First thing to check after the mod is that water is flowing properly : )

 

[czuniga]

Is this it. The short tube looks like plastic.

 

[Johny25]

Thats not the best pic in the world but yes it looks like the correct one. And I cant tell if that is plastic or not but it should be copper tubing. You can always make one from copper tubing from the hardware store. When I bought mine it had no to and I just used the one from my 9.9 square exhaust.

 

[czuniga]

Guy tells me its off a 15 and thats round. I think ill just go for it. Thanks. Ill post better pics once I get it.

 

[Johny25]

Well that exhaust in the pic is definitely round and it looks like the correct exhaust. The lighting in the pic is terrible though. But if it is a fair price get it : )

 

[czuniga]

40 bucks and my carb just came in. Found it on clist gentleman was selling a lower unit and agreed to sell me carb if I would send a prepaid package. For 35 bucks u can't beat it