200 ci reduced idle RPM after tune-up

WhiteHorse-6

WhiteHorse-6

New member
Suggestions on why my idle is now lower than before the tune-up? I expected a better sounding engine!

Replaced plugs (gapped to .035 as per shop manual) and wires (7mm), then started engine as a test. Everything sounded normal. Then replaced the dist. cap, rotor, and points (set to .025). Inadvertantly, the condensor touched the points shorting out and once we figured that out and ensured it wasn't touching, engine would start, but the idle is much lower. To the point that the battery tested with a voltometer only registered 12.2 at an idle. The battery is new, I did not replace the condensor (I asked for the complete kit from Autozone and it didn't come - lesson learned!) I did not adjust the distributor or mess with anything on the carb. Your help is appreciated, thanks!

William
 
Have the battery charged to bring it up to a full charge. When ever you change cap, rotor, and or points, You need to reset or check that the timing is in spec, be sure that point dwell is set right first. Last reset the idle rpm of the carb. Good luck
 
new condencer in now too?

"...expected a better sounding engine..."
what duz it sound like now (also as compaired to B4)?
 
I did not replace the condenser (when I asked for the completer tune-up kit, they did not include one), but as soon as I get the time, I will get one from Autozone. Following the tune-up, it idles rougher and much lower, which I guess is why hte battery does not seem to be getting charged like it should. After putting the trickle charger on the battery overnight, the charging went from 12.2 to 12.6. Still not right, but an improvement. I'll keep you posted. Thanks for the advice!

William
 
Got some time and replaced the condenser, starts up like a champ (better than ever before!), but the battery was still not getting more than 12.6. I'm told the alternator is bad, so I bought a new one from NAPA. I hope to replace it this weekend. Once I have that done, I'll play with the timing and carb idle (it still seems to idle a little on the low side). I bought a timing light so I can check/adjust the timing. Without a tach in the car, is there an improvised way to determine the actual RPM other than by sound?

Thanks again for your help!

William
 
About the only other way to set a carb would be with a vacuum gauge, but like setting it by ear your not going to know the Idle RPM. You should invest in a Tach / Dwell gauge you can use it too set the points as well as the carb mixture and idle RPM. :nod:
 
Whitehorse,

What Bubba said is key. Without a dwell meter, we used to set points at .016-.017 on Fords.

This seems to make them start and run better, however it's only preliminary. I did it time and again with good results. One should use adwell meter if possible, adjust points until 38-40 degrees; then use your timing light and reset timing.

Point gap change will change timing and idle. With no meter, .017 should do you good. You a NAPA/Echlin condenser if you can,their capacity used to be spot on.

Keep it up, have fun.

Gary
 
"...used to set points at .016-.017..."
thickness of the flap on a pack of 'book' matches...
 
.016-.017 on the hi-side. & don't strip the screwhole out in the baseplate. Uh-oh I dropped it. hey, here's that missing needle bearing I needed. Ah, bumper jacks, barrel fuses, pop-in cig. lighters & metal click-clack armrest ashtrays... I'm sorry I'm back. ON a serious note; does your mustang have an external voltage regulator? Make sure whether your new altinator has an internal one or not.You can't have two of them hooked up in the system.
 
Thanks all!

Ludwig, I'll see about buying the Dwell meter, thanks for the link! Like I said, once I replaced the condenser, it started up better than it ever has! I just bought the timing light so I can check the timing and see about adjusting that or the carb, whichever the low idle is from. Since the alternator is bad, once I replace that, I'll see if that had anything to do with a slightly lower idle since it's just taking from the battery and not being recharged. Doubtful, but first things first. I really enjoy learning how to work on my White Horse and can't thank you guys enough. Not just for my question, but reading other Q & A's I'm able to read here.

William (A.K.A. WhiteHorse-6)
 
Since you bring it up, you need to know where the real and true top dead center is in order for your timing light to do you any good. Sometimes the outer ring slips on the damper and the notch creeps away from TDC. There are several ways to find it. Some use the string in the cylinder, others use the stop bolt. I like the finger in the plug hole. It shows you when your are on the compression stroke. Another low tech one is the long rod (screwdriver) in the hole and turn until it just stops rising. Use the search to find what I'm talking about.

Once you find the real TDC, make a new mark with a white pen on your damper ring at the indicator notch.
 
"...with a white pen..."
bringin home that lill bottle of white out from the office supply closet helped me! shows up in the flashin light great!
 
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