Distributor cap wasn't on right...did I damage anything serious?

sigh Well, I was installing new spark plug wires and a new distributor cap and rotor on my 85 Olds Cutlass today.

I did the wires first, one at a time. Then the cap, rotor, transferred the coil over to the new cap, hooked it all back up and started it. Well, TRIED to start it. My brother-in-law was watching the cap while I started the car, and waved at me to kill the engine right away. I got out and he said the entire cap turned about 20 degrees when I tried to start it. The screw/hooks were on tight, but I took off the cap and reseated it…it seated MUCH better the second time, I did not feel it set nicely like that the first time…stupid. Anyway, it took a bit to get it started after that still, but it did start and ran…poorly…I double checked all the wires, they were on the right terminals/cylinders. Took it for a test drive, it ran badly, hesitated and really had to rev high to get any speed. Got home, popped the hood, and smoke was coming from the intake manifold (right side of engine). Looked like old oil that was on the engine was smoking. The temp guage never moved above 190 during the short (3-4 min) test drive. I pulled the cap out completely and removed the rotor…saw the problem, the contact tip on the rotor was bent badly to the side…

SO…the cap looks totally undamaged, so I am going to buy a new rotor tomorrow and install it (making sure the cap is on right this time…) and hope that’s all.

My question is, did I damage anything else when the rotor made contact with the cap terminals, turning it? Why was the engine smoking after the drive, is it because cylinders were not getting spark but still being moved? Should I be checking anything else or replacing anything else?

Feeling sheepish…


Look at the inside of the cap and make sure all of the terminals are intact, and the spring loaded button in the center is intact. If it is, you’re good to go. When you install the cap, make sure the tabs around the inside lower lip of the cap fit in to the notches on the distributor body. Twist it back and forth to make sure it’s seated, and make sure that the spring-loaded hold-downs are in place (something you’re probably familiar with now. :slight_smile:

Should be fine.

That’s a relief. I did check the inside of the cap, amazingly, none of the terminals have any visible damage at all. Any ideas on the smoke coming off the right (driver) side of the engine?

It was probably getting hot from the timing being messed up by the broken rotor.

It’s easier to wreck a rotor than to destroy a distributor cap. The end of the rotor probably retarded the timing, so you had fuel burning after the exhaust stroke was done, burning the incoming air and fuel on the intake stroke and firing back through the intake. That is why it ran badly and heated the intake manifold. That interferes with the intake cycle of all the cylinders, going from vacuum to pressure. The engine is ususlly OK after that.

When you think you are done, check the timing…An episode like this can move things a little…

Thanks, I will have to get a timing light. I’ve never checked timing before, is it complicated?

Also, I’m having trouble finding a rotor with a brass contact terminal (the terminals on the cap are brass)…how important is it that the metal on the rotor matches the metal contacts on the cap?

The metal used in the rotor is not important.

Checking the timing is quite simple. On the harmonic balancer, that big pulley on the nose if the crankshaft, will be a timing mark, a groove or a scale with degree markings. There will be a pointer on the timing cover that will line up with the marks. Use chalk to highlight the correct mark. Then, with the light connected to #1 plug terminal and the battery, start the engine and carefully shine the light on the timing pointer. Be REAL careful of the fan and belts…Disconnect the vacuum line from the distributer advance during this procedure. To adjust the timing, look down at the base of the distributer (is your distributer mounted at the front or rear of the engine?) you will see a hold-down secured by a single bolt. Loosen this bolt (they make a special dog-leg wrench to reach it) so the distributer can be rotated slightly with hand pressure. Then, using the light with the engine running, move the distributer until the marks line up correctly. Turn off the engine and tighten down the distributer and reconnect the vacuum line.

Well, apparently I blew the coil when I installed the distributor incorrectly. I saw the old coil, the metal bracket had melted in 3 parts on the one side…ouch. I also had a few melted misc wires and the metal brush (?) with the spring attached to it beneath the coil was damaged. The timing was way off too, I’m assuming from my rotor incident.

A couple problems…the part # for the coil installed is D505A (ACDelco)…I looked it up on ACDelco’s website and it’s not the right one for my car…I have the less popular Chevy 305 engine, the D505A is for the more popular Olds 307…I need part #D573A according to the site (matches my VIN too - “H”, not “Y” or “9”). Is this a problem?

Second, while I gotta admit the car has TONS more power now with the new coil (I’m guessing more from the timing adjustment and advancement though - 5 degrees), if I punch the throttle, it hesitates, almost like it’s gasping really…just for a second and then takes off…when it does this the RPM’s jump up a tiny bit, then drop to 500 for that second, and then back up as it gets power. It does this at any speed, more noticeable at low speeds. If I gradually give it gas, it doesn’t do this, even if the gradual push quickly turns into hard acceleration. What could cause this? Wrong coil?

I’m posting this same answer in the other thread in case anyone is waiting for a follow up post on that thread only…Please help! I’m taking the car back to the mechanic tomorrow but I’d like to hear your opinions first. Thanks in advance…


Hesitation…Quadrabog …It kind of comes with the quadrajet carb. Check to see that the accelerator pump is working by looking down the throat of the carb (engine off) and open the throttle quickly. You should see a a shot of gas being squirted into each primary bore…You might be able to adjust the amount by manipulating the linkage to the pump…

But it never did this before, why would that all of a sudden change? Seems to coincidental.

Well, I found out the that coil that was put in is the reverse polarity of what my engine needs. So I took it back and am waiting for a new coil in the mail (parts are much cheaper to buy from the States, even after the shipping costs to Canada…plus our dollar is doing ok right now). Hopefully this solves the rough idle and hesitation.

An update for anyone who’s interested…

I received the new, correct coil in the mail today and installed it and what a difference! Even starting is much healthier sounding and quicker. No more hesitation, it idles properly, no stalling at stops, and tons of power. When I really open it up, I can hear a clicking sound coming from the general area of the distributor, consistent with the engine speed…It’s a “new” sound, which I noticed after the timing was adjusted/new dist cap&rotor installed. It doesn’t sound like pinging or like it’s coming from the actual engine. Is this normal?

I’m curious, after I had my incident with the distributor cap being installed wrong and timing getting knocked off, my mechanic said that there was a lot of fuel in the engine oil and they changed the oil but not the filter. How would that happen (fuel getting in the oil)? Timing being off can do that?

Thanks again for everyone’s help…

The fuel is going to the cylinders even if the spark is not.  The fuel does not burn so much of it drains past the pistons into the oil.  Even if it does ignite, if the timing is off, it may not fully burn leaving some to drain into the oil.  Your mechanic was likely correct. 

Pinging can sound a little different depending. It could be many different sources however. Find a length of garden hose and use it like a stethoscope to see if you can locate the source of the noise. It may be nothing other than normal now that you have good spark, properly timed.

If you are not able to located the sound have your mechanic listen to it, he (or she) maybe able to identify it.