View Full Version : Carburetor adjustment

Rippen Griffin
01-16-2009, 12:05 PM
My 79 is running rich, getting ~21 mpg and extremely conservative driving. I have no experence with carbs or where to start adjusting first. If anyone has pics of adjustment points or suggestion it would be greatly appreciated.

01-17-2009, 04:07 AM
not sure about those adjustments, but make sure you have NO vacuum hoses rotted or broken..otherwise leaking while it is running. Also I think that one has breaker points so the points, dist cap & rotor get serviced more often.
I think once you get to access the carb in general you should see a big honking adjuster screw but dont move it too much until you checked the above items.

Rippen Griffin
01-17-2009, 06:31 AM
It is CVCC.

I will look over the hoses. And I read that there are 2 float adjustments

01-30-2009, 11:14 AM
It is CVCC.

I will look over the hoses. And I read that there are 2 float adjustments

Yeah,the CVCC has two float adjustment screws,one big and one small,they are made of brass and you can see them in the top of the carb after removing the filter. I dunno the adjustment of the small one but i assume that the big one has to be adjusted like in the non CVCC carb. There is two methods on adjusting the float level,in a non CVCC carb,one is better than the other,but harder because you must disassemble the thing.
The simplest way is unadjusting the screw(big one) in 1/8 steps,with the engine running,waiting 15 seconds and then another 1/8 step,and so on untill the engine starts to fail(rough idle or engine stop) then,when that happens you must screw it back 5/8 (5 steps).
The hard way (but the best) is by measuring the distance between the lower part of the float and the bottom of the carb with the gasket on it,holding the carb in a manner that allows the float to press the valve but without touching it,letting the gravity do the pressure. The distance must be of 35.4-37.4 mm(from the gasket) I will add a pic showing the procedure because my english sucks!
I hope the info is worth the effort of reading this. :pc::bowrofl:

01-30-2009, 12:05 PM
Picture from the shop manual explaining the process.

07-24-2010, 06:08 PM
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07-25-2010, 04:40 PM
can anyone tell me how to delete the evap system in my 87

Wrong section. :bandance:

07-25-2010, 07:47 PM
My feeling on carbs is that they are a mandatory overhaul item every 100k miles or so. Carbs can have a half-dozen different adjustments including float, air mixture, idle speed, choke, AC idle, etc. etc. Usually if something is coming un-adjusted, it's because it's failing and is going to leave you stranded soon. On the older CVCC carbs, it was very difficult to adjust the floats. You basically measured them before you bolted the carb together and hoped for the best. On the 1982 CVCC motors, the carbs had sight glasses built into the side that allowed perfect on-the-car float adjustment.

If you don't have the sight-glasses, I'd look into swapping a sight-glass carb onto the car. Find a decent scrapper from the yard, rebuild it properly and swap it on.