Hi guys..
I have a 66 Delta 88 with the 425. It runs good but a little sluggish dieting acceleration. I'm guessing its a Carb issue. I'm going to do a full tune up on it this weekened and I am wondering how diffecult or easy it may be to adjust the Carb. I'm fussing its original factory. Any advice helps thanks.

 

"Dieting?" "Fussing?" Help!



I have a '67 Delta 88 with the same engine, and I would do a tune-up as you say. Make sure that includes new points, rotor, condenser, etc. and that you check the dwell.

I would also check for vacuum leaks. I would rebuild the carb if it's never been done. I did it on mine, even though I had never done it before, and it was really not a problem. Take photos as you go so you can look at them as you put it back together. I got a rebuild kit for about $15.00 at my local Autozone.

Adjusting the carb is easy. Just turn the screws. Make sure to count how many turns it takes to remove them if you do a rebuild as you'll want to reinstall them to the same degree when you reassemble so that you're at least at the same point you were before when you start making adjustments.

I would make sure to change the fuel filter, which is right there at the carb at the point where the line from the fuel pump attaches. It's a $2 part at Autozone (or anywhere else), and you'd be surprised how little crud needs to be accumulated in there before it starts to restrict fuel flow.

In fact, I would do the fuel filter first as it's easy, fast, cheap, and might be all that's needed to fix your problem.

 

A tune-up would be a good thing. You may want to check vacuum advance mechanism on the dist as well. You should as mentioned check vacuum lines for leaks and even consider changing th carb base gasket as this part gets overlooked. You should also check timing with a timing light. As for adjusting the carb the mixture screws only control idle circuits and not driveability for the most part.

 

Too much guessing. Check it out and see what you've got. Lots of things get changed over 45 years.

Good. As Jaunty says, that's exactly the right thing to do.
Many different things can cause your symptoms, and you've got to check everything out before you can be sure what's wrong (or whether it's a little bit of everything).

Its not hard. I'd recommend following the procedure in the Chassis Service Manual, but the basic details are all the same:
Examine, clean, and adjust points (dwell angle)
Check cap, rotor, wires, plugs, coil.
If necessary, replace some or all of above.
Set timing.
Rebuild carb, bench adjust as per Chassis Service Manual.
(Remember - the way to keep your old mixture screw settings is to turn them all the way IN, counting the turns, then remove them. For a starting point, screw them all the way IN again, and count the same number of turns out from there.)
Check vacuum, use vacuum gauge to help adjusting carb. (idle speed and mixture screws).
Replace fuel filter, check fuel hoses - it they're cracked, replace them.

- Eric

edit: also, what OldsManiac said: Check vacuum hoses and advance diaphragm!

 

Just in case you don't have the CSM (Chassis Service Manual) with the info about tuning? Here's a link to the 66 CSM dealing with tuneup: http://wildaboutcarsonline.com/membe...ections_6C.pdf

 

Check the mechanical distributer advance by twisting the distributer with the rotor off - should move free, and snap right back.
While the plugs are out, you can easily check the timing chain stretch by moving the lower pulley, both ways, and seeing how much travel is required to move the rotor.
More than an inch, you should consider replacemant!
If you do the chain, do the $25 water pump, too.

 

Thanks guys will do as much as I can and ill keep you posted. Thanks for that link too.