New Carb - Several questions.

[joe40]

Ok. I got my new carb from Marshall today and it's looking pretty sweet. A couple of questions. When I removed the old carb and looked at the block that it mounts to I noticed red sealant had been used. I've read some posts here that said not to use sealant... so should I remove this and clean it all up somehow? (I hope not)

Second question: The Marshall carb doesn't have a place for the return fuel line. Do I just plug that hose at the gas tank and remove the line?

Third question: What do I do with the little port on the side of the carb? (obviously this is a no-smog carb) It's the little vacuum line looking port down near the mounting holes in the picture.

 

[Splangy]

That little port at the base of the carb is for your vacuum advance line to the distributer. And yeah, get rid of the silicone.

 

[joe40]

So, do I take it all apart and clean off the sealant? And then what? Isn't there supposed to be a heat sealed gasket attached to the block? Do I have to get another gasket? I wonder why the red sealant is there in the first place.

 

[edwjmcgrath]

Good questions. I just heard that my carb shipped today so I'm sure I'll have issues too.
My stock advance port is on the other side of the carb. I can deal with that.
It seems like we'll need either a gasket or gasket substitute under the carb.
Looks like your gasket is intact unless you plan to mount it on top of the air filter as shown.

 

[joe40]

The top gasket looks good. I'm worried about the seal on the bottom of the block where all the red goo is coming out. It may be sealed just fine so I hate to start messing with it, however it may be not so good and need redoing. I just want to be sure I'm doing this right while I'm here. Was all ready to bolt in place when I saw the red goo. Also, the mounting bolts were not very tight... is this normal? Top of the air filter is as close to home as it got tonight.

 

[sepr2]

I would clean that all up and use new gaskets. No reason not to with a new carb. Nuts should be tight within reason. Why risk a vacuum leak with a new carb and its all apart anyway...Just sayin

 

[Copenhagen1]

I just got my new carb as well and just installed it this weekend on my 77 so I am familiar.

The port mentioned is indeed the vacuum advance for your distributor.

You definitely need to SEAL the return line. When you start driving around, the tank builds up pressure and forces raw fuel back through the line and it pours out on your intake/exhaust manifold. VERY UNSAFE. Ask me how I know. I took the gas cap off to get it home about a mile away. Catastrophe avoided. I just couldnt wait to test drive it.

That paper gasket you have on top of the block, you need another just like it on the bottom. Be very careful scraping the red goo off the bottom of the space because you can easily damage the mounting surface. That might be what happened with the previous owner and why the goo is there in the first place.

 

[joe40]

What is the best way to seal the return line. Do I seal it at the carb and leave the line intact? or remove the line and seal it at the tank? What do I seal it with?

 

[mossman40]

I've got my trollhole carb on the way soon. I got the return line tapped on the carb. You could just leave the line intact and plug it up right at the carb or you could remove it. Either way would work. Maybe just as the line heads down into the frame would be a good place. Haven't gotten mine yet, but all I'm worried about is removing the proper smog goodies. Good luck and let us know how it runs.

 

[madinal]

I removed the secondary line and plugged the rubber part just as it decends from the tank. I used parts of it and the primary line as needed when I mounted the electric pump and filter on the frame rail. A bolt with a few wraps of tape and a good clamp worked for me.