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Engine problem while at the track yesterday. (FIXED)

A

Anonymous

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Thought I'd put this all in one place on the off chance someone is willing to help :eek:mg

While at the track yesterday, the car ran great during the first session: HPT 9110 session 1.avi

The second session went downhill fairly quickly. At about 1:30 of this video: Uh Oh.flv which was only the warm up lap, the car starts missing and popping right after the 4-3 downshift into turn 10. I wasn't going that fast and the car did not over rev.
The miss is constant, but gets worse as the go pedal is applied. If I let off the gas or put it in neutral/out of gear it dies. It will not run without applying copious amounts of fuel. It will start up and run, but poorly.

The Optima red top is at least 6 yrs old, maybe 7. It sits with a reading of 12.44 volts. Cranking, it drops down in the 11 range and when running it was reading 12.11 volts.

I have a MSD 6AL box, MSD Blaster HVC 42,000 volt coil and a stock type Motorcraft dist with electronic ignition. I looked at the cap and rotor and while they don't look trashed, they are worn.

Any ideas are welcomed before I start digging into it this weekend. I'd like to rule out electrical or any easy fixes before I dig into the engine.
 
Re: Engine problem while at the track yesterday.

IMO it looks like your alternator took a crap. I may be wrong but the reading of 12.11 while running looks low. Shouldn't it be up around 14.5 while just running? It would be great if that's all it is. The MSD requires about 12.00 just to run or it will malfuction. Correct?
 
Re: Engine problem while at the track yesterday.

"silverblueBP" said:
...... when running it was reading 12.11 volts.

Any ideas are welcomed before I start digging into it this weekend. I'd like to rule out electrical or any easy fixes before I dig into the engine.
Click to expand...

I don't know about your miss problem, but you definitely have a charging system problem. Most likely a bad alternator but could be a bad regulator also. As 6T6red stated voltage while running should be in the 13.5 to 14.5 volt range.
 
Re: Engine problem while at the track yesterday.

That's what I was kinda thinking, but I'm "electrically challenged" and need expert advice. How would I check the alt output at the alt? The reading I took was at the battery posts. Or, does it even matter to test it at the alt?

Could I jump my battery with a good battery and see if it clears up?
 
Re: Engine problem while at the track yesterday.

If you want the farmer method of checking an alternator, here you go.

With the engine running, take a long screwdriver and hold it near the back of the alternator (with the blade running across the entire back of the alternator but not touching).

You should feel a magenetic tug on the screwdriver (pulling it towards the alternator) if the alternator is actually working.

Sounds like a regulator/alternator problem if you are only reading 12+ volts at the battery with the engine running. 14+ is the norm.
 
Re: Engine problem while at the track yesterday.

On the back of the alt, the large post should be putting out over 13 volts dc on a meter when running. Or...

Take the alt. to a local parts store and they will check for free. If it checks good, get a regulator.
 
Re: Engine problem while at the track yesterday.

No regulator, it's a one wire Powermaster 100 amp alternator. I found the receipts for the alt and battery; the Optima is 7 yrs old and the alt is 8 yrs old. I put the car on the road mid 2004.

I now run a power inverter to keep my camera charged while on the track. If the alt is shot (likely) would it be good, bad or indifferent to go to a 140 amp alt?


I can't complain about them lasting that long.
 
Re: Engine problem while at the track yesterday.

Just went out and checked the alt. Took my multi-meter and ran the pos to the back post of the alt. ran the neg to a ground. With the engine off but the main switch on it was reading 12.48 volts (same as right at the battery).

Started the car up and the volts dropped to 10.89! and that was with it rev'd up to keep it running. So, am I correct in thinking that the alternator is shot? I need to get one so I can go back to the track next Sunday!

Stay with a 100 amp or go with a 140 amp?
 
Re: Engine problem while at the track yesterday.

I hate you
 
Re: Engine problem while at the track yesterday.

Now is the time to upgrade if you desire to. Really your call....
 
Re: Engine problem while at the track yesterday.

I think it's the nut that connects the seat to the steering wheel.
 
Re: Engine problem while at the track yesterday.

Alternators are like wallets and peckers - they can never be too big
 
Re: Engine problem while at the track yesterday. (updated)

Changed the alternator out with a new one. Now I'm getting the proper charge to the battery :vic

It didn't resolve the misfiring issue though. I changed out the cap and rotor with new ones, no change. Pulled the carb off and opened it up to see if there was any debris blocking the jets and it was clean.
Pulled the plugs, checked the gaps, checked the wires, all were OK. Went through each plug wire grounding it out to see if the spark was going through. Had a nice blue spark from each one. Getting the same reading at the battery as well as at the solenoid up front while grounding to the engine.

Turned the motor over and looked at each valve, they seemed to be opening all the same with no weird sounds. It will not run at idle so I can't see what the timing is at. If I advance the timing about 8* it runs better but the timing light shows 30* at about 1,200 rpm (normal idle).

I'm running out of electrical ideas and am now leaning towards a timing jump. I took the distributer out and the gear looked fine. The cam gear looked OK as well. I suppose the cam bolt could have backed out and let it move if the pin sheared or came out (dbl roller chain). The only thing, is that it has not changed or gotten worse since it started this misfire Wed.

I have fuel (6lbs), compression and spark.

Any ideas?
 
Re: Engine problem while at the track yesterday. (updated)

Verify the timing.
Run #1 to TDC and check the bal for correct mark, then look at where dist is pointing.
Its a shot in the air ,but did you look at the dist gears shear pin?
Your startment of if I advance it it will run makes me lean towards the dist gear has moved.
 
Re: Engine problem while at the track yesterday. (updated)

Try a different coil. If that doesn't fix it put a point driven dist. in it with a regular coil to see if it's the box. It sounds like your ignition is breaking up. If it jumped timing it wouldn't misfire like that IMO.

Something broke, it was running fine, you going up in RPM and poof. Could be the pick-up in the dist. Something's not making the coil hit everytime. Changing the ignition over to a set of points and a regular coil will give you some answers.
 
Re: Engine problem while at the track yesterday. (updated)

Get a wooden steering wheel
 
Re: Engine problem while at the track yesterday. (updated)

Thanks, those are both GREAT ideas.
 
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