17085213 1585 hpb

[bober]

Can you guys tell me what this Q/jet is for ? 17085213  1585   hpb

[carmantx]

1985 chevy pickup I think.

[Ethan1]

1985 chevy pickup I think.

 Yep.

[bober]

Is this a popular carb at all or just another q/jet ?  Looks wise it seems nearly new or rebuilt but no tags or stickers !

[omaha]

its a good starting point for a rebuild and can be made to do what you want it to do. the good is its a M4M carb with an electric choke, adjustable APT, better needle and seat setup. somewhat bad is that its a single main airbleed carb and is usually setup on the lean side from chevy.  dont know rods/jet combo offhand.

[Ethan1]

its a good starting point for a rebuild and can be made to do what you want it to do. the good is its a M4M carb with an electric choke, adjustable APT, better needle and seat setup. somewhat bad is that its a single main airbleed carb and is usually setup on the lean side from chevy.  dont know rods/jet combo offhand.

 .075" Primary Jets
 61S Primary Metering Rods
 EF Secondary Metering Rods

 Stock specs above.

[firefox3]

.075" Primary Jets
 61S Primary Metering Rods
 EF Secondary Metering Rods

 Stock specs above.

Thank you for the specs. I recently purchased one of these and those are the rods and jets in it. Idle tubes are .034".

What's the deal with "S" metering rods? I thought most of these single bleed models used "M" rods.

Also, do you happen to know the part no. for the power piston spring? The one in this carb. is super long.

Thanks...

[Ethan1]

 After 1980, Qjet part numbers came in "kits". So, power piston and spring kit was 17111347.

 I know the "S" rods are full taper, but that is about it. Cliff would know more.

[firefox3]

I wasn't aware of the "kits" for models after 1980. I learned something new.
I'll replace the PP spring with one from a late 70's M4.

This 1985 carb. is a bit of a strange animal...to me at least. Things I have noticed so far:
 
The plug normally removed for adjusting the APT screw is noticeably larger in diameter and has a collar that extends down about .250" below the bottom of the air horn. Apparently it's purpose is to keep someone from turning the APT screw too much CCW and richening up the mixture. I'll cut or grind it off.

The idle channel restrictions are quite large in stock form.

Also, I noticed the secondary wells have a vertical divider that seems to me would reduce their volume. These "dividers" are part of the casting and not removable. Not sure why Rochester did this.

I'll replace the "S" rods with some "M" rods from Edelbrock.

[bober]

Thanks guys for all the information ,appreciate it !!!!

[Cliff Ruggles]

The 17085212 and 213 carburetors were used on 454 BBC's in HD Truck and Motorhome applications from what I've seen.

They are far different than the other q-jets produced that year, and take special gaskets as well.

We've sold a LOT of kits for those in recent years, they are excellent units and not nearly as conservative in fuel delivery as the standard q-jets produced in the same era......Cliff

[bober]

I had a chance to try it on a 350 truck and actually ran well but had some leakage from what appeared to be around the throttle shaft . I'm thinking poss N/S or float adj. ?

[Ethan1]

I had a chance to try it on a 350 truck and actually ran well but had some leakage from what appeared to be around the throttle shaft . I'm thinking poss N/S or float adj. ?

 What are its symptoms?

[bober]

Gas drips from the throttle shaft area on exterior on to manifold while idling and after it's shut off but it didn't run bad . 

[mcx]

Cliff...do you recommend removing the secondary well cast-in dividers on these  Qjets? I guess some careful drilling could be done?