Thermoquad with no step up lever?

[Robking]

Hi folks, I apologize if this is common knowledge but my googling hasn't yielded anything. I was taking apart my thermoquad in preparation for rebuilding it, and freaked out when I realized that I had (I presumed) lost my step up lever from the throttle plate. I was trying to be extra careful along the way, including taking pictures periodically to help putting it back together.

From looking at the picture (the gasket stuck to the throttle plate), I don't think the thing was ever there since the gasket should have held it in place. Not to mention the cam looks like it's not had anything riding on it. This thing came off a motor home, would that even be possible? Or maybe someone rebuilt it over the years and left it out.

Any help is greatly appreciated, not sure what to do other than sell my rebuild kit on ebay and buy a new carb (the odds of getting another one are slim to none I would think).

 

[Aeronet]

How odd. You could buy a rebuildable core for cheap and put the lever from the core in it. Did it work without the step up lever? Might look and see if anyone sells one.

 

[rumblefish360]

That lever is to provide a mechanical enrichment. I’m pretty sure I have a spare one.
Pm me your address. I’ll send one out to you.

 

[Robking]

Thanks so much Rumblefish, sent you a PM. I can't see how the thing could run remotely well without it, but I never heard it run (basically only ended up using block and crank). I must have lost it when separating the body from throttle plate but I'll be damned if I can figure out how and where it is now.

 

[383man]

As rumblefish360 said that just adds mech enrichment by mechanically moving the metering rods. But many carbs work with just vacuum controlling the metering rods so it may have still ran ok. But when Emissions got tighter in the 70's they wanted more control over the fuel mixture since the cars were getting run leaner and leaner so that mech part is a good idea and since they were running carbs leaner that helps make sure the rods lift when they should. Good luck with it. Ron

 

[Dana]

What is the number on the rear of that carb?

 

[Robking]

Yeah, it does make sense that vacuum & spring action of the metering rod piston is
what does most of the work. The lever seems to be there to lift the rods out of the
jets quicker (making it richer) as the throttle opens. Either way thanks to Rumblefish
it now has one.

My best guess is it's a 6518 (not sure why the strange double stamping).

 

[rumblefish360]

Wow! Never seen a double different number stamping. That’s weird.

The mechanical lever is there to insure as well as activate the enrichment quicker under a quick throttle stomp.

 

[pentahead]

I have seen alot of double stamped, even with 2 different model numbers..