1987fbd

I have found the two cross refrence carbs for the 1708 series Q-jet in 87. They are the 9906 which is the Emissions model and the 1406 which isn't. My question is they are both $259.00. I need to stay legal so I cannot use the 1406 which every parts store stocks around here. Does anyone know what the difference is and can I modify the one to have the smog items on it. I am cosidering this purchased based on my carb is just shot. I have been told that a rebuild kit is not going to help my situation any cause it is shot. And a Rochester carb is going to run me 100 more, except I do see a bunch of different 1708 series carbs on Ebay. Do I need to use an exact 17087306 or can I use for example a 17082224? Any suggestions, has anyone done this? Thanks in advance.

Mark

five7kid

iTrader: (14)

There's no such thing as a new, "replacement" emissions carb out there for 3rd gens, because none of them are CC. If you have visual inspection (and the inspector has a clue), you're going to fail for that. Also, without a CC carb, the SES light is going to stay on - if you take the bulb out, it won't come on when the ignition is first turned on, so again if they know what they're doing, they'll fail you for that.

If all you have is a sniffer test, then you might be able to get even the non-emissions 1406 through testing. But, your chances will be reduced over a CC q-jet (feedback control works).

I don't know what's wrong with your current carb, but short of severe warping or cracks in the bowl or airhorn, it should be rebuildable. The throttle shafts can be rebushed, even. I've seen q-jets that weren't salvagable, but they're the exception (and all were abused).

I also can't provide details about carb numbers, but most any 305 CC SBC carb should be workable. If you went to the parts store for a rebuilt CC carb, for instance, the chances are it would not be the same number as your current carb, even though it is the right one for your applicatioin.

1987fbd

Hi 57, man i am glad your on here. You have been alot of help for me. I had no idea they weren't cc controlled. Well that is out then.
I believe Idaho is visual as well and sniffer.
I am fighting a high idle problem and they told me it was because my carb needs to be rebushed. At least that is what the guy on the phone from carbs unlimited told me. My choke is wide open cause I had to wire tie it open or it would be almost shut. It idles at like 1400 rpm and the screw is backed all the way out. I was considering replacing the tps sensor? Do you think that will help me out any. Sounds as though the carb kit doesn't come with much. And it sounds like I need alot of things that aren't in the kit.
Well thanks again.

five7kid

iTrader: (14)

I doubt your TPS sensor has anything to do with your problems. Sounds more like choke thermostat/linkage malfunction. Throttle shafts may also be worn, but I doubt it.

A rebuild will allow you to disassemble the carb, clean it up, and replace the gaskets & rubber parts that degrade over time and/or would be destroyed by the disassembly process. Float, choke thermostat, TPS, MCS, etc., are purchased separately if needed.

You might do okay with one of those Ebay carbs. I'd try to establish whether it came off a 3rd gen (American, not Canadian version), but even that probably isn't necessary. You might also take a look at the classifieds on this board, as one of our own is less likely to mess you over (although still no guarentee, I suppose). If nothing else, you'd have parts to make one out of two.