1971 Evinrude 18 hp fastwin help

[StinkyPeteJones]

Folks,
Firstly, thanks for accepting me into the community this website has already been a great help.

Now to my issue. I inherited a 16' deep v from my grandpa and it came with two motors, a 1986 Evinrude 15 hp and a 1971 Evinrude 18 hp fastwin. I've been trying to work on the 18 hp first cause who doesn't need more hp. I rebuilt the fuel pump and the carb so far. I'm having trouble getting the fuel mixture right but that's beside the point I assume it's mostly trial and error. However after rebuilding the carb it runs amazing with the cowl off but when I put it on the motor it is super doggy. Won't climb rpms and dies rather quickly when trying to idle out. Also another thing I noticed was there was a milky white film coming out of the carb throat and also started showing up in random spots on the motor. I live in Missouri and right now it is ridiculously humid which I read on here might be part of it. I hope my rambling makes sense to the boat experts on here cause I'm at a loss. Thanks in advance!

 

[user 21074]

Possibly exhaust leak and it is sucking it in the carb.

 

[Pappy]

The white residue is nothing to worry about.
As far as the cowling issue goes do yourself a favor and take a look at the air inlet on the motor pan. On yours I believe it is located under the carb?
You may have critter matter built up in that area blocking off air flow. Also, if you do not have this on your model then check the upper cowling at the rear and follow the air inlet there and look for blockage. Let's start there.
Welcome to the forum by the way!

 

[StinkyPeteJones]

Oh man, thanks so much for the quick responses. I did read on here about the exhaust leak being a possible issue where would I check to look into fixing this. As far as the air inlet I lost a nut to the carb in there when taking it off so I know it's not caked full of stuff but now that I know what that area is I'll go ahead and clean whats there out.

 

[CedarRiverScooter]

I have same motor & ended up taking it all apart. It seems daunting at first but really is not hard if you do it in the right sequence.

I ended up replacing just about every wear part on mine so now it is good to go for the next 30 years.

While you have it apart, it is a good time to repaint it. I used Ford dark blue from rattle can plus some generic clear coat. White rustoleum for hood. New decals are about $50 & make it pop.

The white slime is due to condensation on carb (carb body cools off due to Bernoulli principle). water & oil film = milky

 

[StinkyPeteJones]

Thanks cedarriver I planned on repainting and making her look brand new just didn't know the paint code I could use for oem look.

 

[StinkyPeteJones]

Do you guys think it would be fine to use that permatex high heat gasket maker stuff or should I keep look for the actual gasket. Only reason I ask is I'm having a hard time finding the gasket online.

 

[CedarRiverScooter]

Which gasket? Marine engines has just about everything available.

 

[StinkyPeteJones]

I guess I should look there

 

[Pappy]

Do NOT use silicon in place of a gasket or use it on a gasket! Source your gaskets and do the job properly using proper sealants and parts.
If you have a severe enough exhaust gasket leak then you should be able to see the smoke coming from between the powerhead and the exhaust housing. Do you?

 

[StinkyPeteJones]

Well I’m honestly not able to tell. I added some seafoam to my gas mixture in an effort to clean the ol girl out so it’s got a bit extra to the exhaust. I planned on dumping that mixture and get new to look into the exhaust leak.