RTV gasket maker in carb

[CajunWon]

Since no one can determine the correct parts for my motor (Johnson Model # J130TLEOP):

Marineengine sent an incorrect kit, though it was close enough to use 2 (of 6) parts after modifying one. Modified the ring gasket which mates the carb to intake by cutting off one small circle intended for a bolt which does not exist on my motor. Did this for one of 4 carbs and since then have >50% improvement.

Rather than chance a 2nd incorrect shipment: Was thinking to use Permatex RTV to make a gasket to mate the plastic carb against the metal intake manifold. Thinking about leaving the current ring gasket in-place and adding a thin line of this Gasket Maker to make a proper seal.

I believe the current 15yo oem gasket allows air to pass causing a lean condition, hard starting and poor idle.

tia

 

[BigB9000]

Re: RTV gasket maker in carb

RTV isnt the best stuff.
you could get some gasket paper from your local parts store, in about a 10x10 sheet, and cut your own.

 

[mrcj001]

Re: RTV gasket maker in carb

RTV isnt the best stuff.
you could get some gasket paper from your local parts store, in about a 10x10 sheet, and cut your own.

.....and use Permatex 2...just a dab

Not RTV

 

[RogersJetboat454]

Re: RTV gasket maker in carb

RTV is not meant to be used anywhere in a fuel system. The fuel will quickly degrade the RTV, and you will be in the same position you're in right now. I don't know the HP or year of your engine, but have you looked here for a gasket set http://www.laingsoutboards.com/newpage4.htm#JOHNSON EVINRUDE Includes Gale, Sea King up to 1963, and others . Or Like the other poster said, your other option is to cut a gasket the old fashioned way. Get a roll of fuel grade gasket paper, a sharp exacto knife, and trim the gasket paper to the shape you need.

 

[CajunWon]

Re: RTV gasket maker in carb

Found this from Permatex:

MotoSeal? 1 Ultimate Gasket Maker Grey
For two and four cycle engines. Solvent-based bond fully seals within 20 minutes. Forms a tough flexible bond that is highly effective on irregular and uneven joint surfaces. Ideal for use on frequently disassembled engines. Resists gasoline and other damaging fluids. Withstands temperatures 350?F (177?C) continuous, 400?F (204?C) intermittent.

 

[jrs_diesel]

Re: RTV gasket maker in carb

I used Permatex Blue RTV on my scooter's carb before. Not an outboard engine I know, but it is a carbed 2 stroke.

The RTV worked for about 2-3 months, but then the scooter started running funny. That quickly progressed into that it would start and idle, but nothing beyond idle. I pulled the carbed to clean it and found a mass of RTV in the carb bowl that looked like jelly. It was clogging up my main jet. I scraped all of the RTV off and cleaned the carb good and all was well again for my scooter.

Moral of my story: I don't use sealant on fuel systems anymore. Just the specified gaskets.

 

[RogersJetboat454]

Re: RTV gasket maker in carb

The important thing to keep in mind is that it RESISTS gasoline. That doesn't mean that its gasoline proof. That type of language says to me that it can come contact with gasoline occasionally and not turn to goo, but shouldn't be used for sealing something that comes in contact with gasoline on a regular basis. Did you look at the rebuild kits on the website I posted Cajun?

 

[CajunWon]

Re: RTV gasket maker in carb

Did you look at the rebuild kits on the website I posted Cajun?

thx, I did visit the page, but appears to be just part# lists without application guide to assist in locating required items. Will look for "gasket paper" sounds like a great idea.

 

[RogersJetboat454]

Re: RTV gasket maker in carb

The gasket paper should do the trick. It's what allot of repair shops did for gasket replacement back in the day. It's an old school dying art, but done right is just as good as a factory cut gasket.

A few things to keep in mind;
Have patience when cutting one out, you may have to practice making a couple before you get it just right.

I also recommend you start with a piece of cardboard (free), then cut it to match the shapes and openings you need to cut for the gasket to match the carb, intake, bolts, etc. Then trace your new cardboard template onto the gasket paper, and you should be in the ball park with some careful trimming of the gasket paper.

And one final tip, if you need to make holes in the gasket (bolt holes, intake hole, etc), find a socket in your socket set who's size is about the same diameter as the hole you need to make. Set the socket in the spot where you need to make the hole in the gasket, then give it a couple of moderate taps with a hammer. The socket opening will cut nice neat holes in the gasket for you.