Choke assembly gasket

[Big Jay]

Hey guys, my first time posting here and I'd like to take the time to say thank you Lord for providing me with this knowledgeable site.

That being said, I'm reviving a '68 Evinrude Big Twin 40 (40853a) and am in the middle of rebuilding the carb. Once dismantled I cleaned it with Evinrude\Johnson Engine tuner as per the advice from my local dealer. Worked great, however it did chew up the gasket between the carb and automatic coke assembly. I didn't want to mess with the choke if I didn't have to, but seeing as it was providing a leak, I kinda had to take it apart, clean it and re-seal it.

My question for you is this: The carb kit I ordered had no gasket for this piece and the dealer says it's NLA. So I'm cutting one out myself, what material should I be using? Is it pressurized or is it just keeping the metal off the metal?

Also... Should I be using a sealant on the carb gaskets? If so what type?

Thanks so much in advance

Big J

 

[Daviet]

Re: Choke assembly gasket

Do you mean #60 or 46, looks like they are available.
There is exhaust gases that pass through, but not much actual pressure, you can make it out of regular gasket material.
http://www.ishopmarine.com/ishop/js...CatFilter=BRP&eCatSupFldr=supplier-100-005-EJ

 

[Big Jay]

Re: Choke assembly gasket

Do you mean #60 or 46, looks like they are available.
There is exhaust gases that pass through, but not much actual pressure, you can make it out of regular gasket material.
http://www.ishopmarine.com/ishop/js...CatFilter=BRP&eCatSupFldr=supplier-100-005-EJ

Alright... I figured I was ok, but better to be sure. Thank you, it is #46 I was talking about. Weird my dealer says nla, hmm.

My next question is about the heat exchanger tube running from the exhaust manifold to the choke. At the manifold end, is it supposed to be tight in there with a compression nut? There is a nut there but it differs from the one at the choke end in that it doesn't tighten it down. The tube is also different in that the end at the choke has a brass piece attached which the compression nut pushes onto. The manifold end has nothing on it, and just seems to sit inside it's opening leaving it un-sealed. Will this affect the operation of the Heat/Electric choke?

 

[Big Jay]

Re: Choke assembly gasket

Alright... I figured I was ok, but better to be sure. Thank you, it is #46 I was talking about. Weird my dealer says nla, hmm.

My next question is about the heat exchanger tube running from the exhaust manifold to the choke. At the manifold end, is it supposed to be tight in there with a compression nut? There is a nut there but it differs from the one at the choke end in that it doesn't tighten it down. The tube is also different in that the end at the choke has a brass piece attached which the compression nut pushes onto. The manifold end has nothing on it, and just seems to sit inside it's opening leaving it un-sealed. Will this affect the operation of the Heat/Electric choke?

Sorry, lol I just saw in that same schematic it is indeed supposed to have a compression nut at both ends as well as a sleeve ball. Thanks for the link man !

 

[Daviet]

Re: Choke assembly gasket

You're welcome, hope it will help ansewer your questions. If you need more assistance, just ask, there are a lot of experienced people here that are glad to help you out.