Carb base gasket replacement

[rbh]

1985 merc 260 rotchester 4mv carb
OK, so it seems that the poor idle I was expierencing was from a cracked base gasket.
Would it be better to use the thicker base gasket, or the skinny stock one??

 

[joenapier]

Re: Carb base gasket replacement

My experience a few months ago is I could not get a low enough idle set after a complete rebuild of my Quadrajet. The engine would die under 1200 RPM and it was unresponsive to adjusting the two air/fuel mixture screws on the outside.

I squirted starter fluid around the base and heard the engine change - it must have been leaking air.

I got a thicker gasket with a metal mesh layer inside it and now it runs fine.

 

[Danny Mc]

Re: Carb base gasket replacement

I always use the thick gasket better sealing and insulates against heat. I see folks tightening carb bolts way more than necessary and distorting the carb base and gasket.

 

[rbh]

Re: Carb base gasket replacement

Ok, so I replaced the base gasket on the weekend. WHAT A DIFFRENCE!!!
Took it to the lake let it warm up, put it in gear, and went to adjust the idle fuel mixture screws.
I set the idle screw for about 800 rpm, then started adjustment.
I was 2.5 turns out to begin with, but for some reason and I think the linkage
IE, the spring.
Is not tight enough to pull the carb partially closed at idle.
and had a heck of a time trying and failing to set the jets.


Any words of wisdom???

THX
Rob

 

[jtmarten]

Re: Carb base gasket replacement

Remove the throttle cable from the carb linkage, then adjust the carb, then adjust the cable end at idle.