Newbie needs help alternator maybe

[QMCMSS]

I think I'm getting electrically screwed. 1991 ZR1 with 51k miles I bought it about a month ago, Symptom, about 2 weeks ago I go to start her up after stopping at the store and I had no as in zero electrical power the car ran fine ten minutes before. Called my buddy to bring my jumper box as I assumed the new battery had gone dead. While waiting for him I give it another try and varoooom the world is wonderful. Probably should have put the meter on it when I got home but things looked good and the voltmeter on the dash indicated I was charging. I used the car a little over the next 2 weeks and everything seemed fine. Went cruising yesterday and made a few stops. Kept a close eye on the voltmeter and everything looked normal throughout the day. Also noticed that my after market sound system was having problems kind of reminded me of a skipping record, hindsight makes me think it was loosing power for a nano second. After my last stop the skipping got worse and the car began to sputter, I think I was running on the battery, a quick look at the dash meter and she indicates trouble only a little more than 8 volts. And of course she shuts down in traffic. Call AAA the car starts with a jump but quickly starts to sputter and I have her towed home. Once she is safely in the garage I open a bottle of bourbon and opt to deal with the problem the next day. So here I am battery voltage was low this morning so I've got her on the charger and will check alternator output after the charge. I'm thinking the alternator died a slow death and I will have to replace it. So after looking at a number of posts it looks like I'm in for my first plenum pull. If my alternator diagnosis is correct while I have the plenum off I wondering what else I should do and what parts do I need to assemble before I get started, again after reading a few posts I'm guessing coils and injector upgrades are in order, also the posts indicate that getting the correct alternator may not be as simple as I wish. Any help or suggestions etc. would be much appreciated.

[Mystic ZR-1]

The alternator can be removed without a plenum pull.
The correct replacement can be obtained along with a lot
.of good advise from Jerrys Gaskets

[jrd1990zr1]

Originally Posted by Mystic ZR-1

The alternator can be removed without a plenum pull.
The correct replacement can be obtained along with a lot
.of good advise from Jerrys Gaskets

Although it is possible to switch out without pulling the plenum it is far easier to pull the plenum and switch it out. Last year in Carlisle, Mystic, Jim Voter and I changed one out in the hotel parking lot without pulling the plenum. I think it was more difficult this way. I would still be in Carlisle if it wasn't for them.

Good Luck.

[batchman]

Perhaps our story will be of help.

Bought 91 ZR-1 and struggled with several electrical issues. Turned out the stereo installer had used an inch adapter in the metric battery. Removed stereo power (this is a race car, still need to remove the stereo "ballast") and replaced the battery, ditched the adapter and used a correct bolt - all is good.

Good luck, I think you'll be back to enjoying a bourbon shortly.
- Jeff

[QMCMSS]

Ok after several cups of coffee reading some more posts and some testing things don't look as dark. Pretty convinced that it's defenitly the alternator . After fully charging the battery voltmeter reads 12.6V with everything off and the engine started right up meter reads 12.2 with the engine running definetly not the 14.5 I would get if the alternator was working dash voltmeter looks like around 10 and the battery red light is on in the instrument status display. So I'm going with alternator. Found a very detailed post on how to, need to learn how to loosen the belt and I'm gonna go for it. Is their a definiteve answer to "where can I buy a replacement.

[QMCMSS]

Trying to tackle alternator removal myself without removing the plenum. Someone wonderful sent me a step by step and I had to skip step 1: Remove the air horn. Followed the remaining steps and the alternator is ready to come out but not until I remove the air horn. I removed 4 torx screws 2 external and on the top of the airhorn and 2 inside the horn on the bottom. The sucker won't budge. Pretty sure their is something else holding it on but can't for the life of me figure or see what it is. Really could use a step by step for air horn removal if it exists. Is there a gasket between the horn and the plenum that could have to much sealant. I looked at trying to pry it loose but don't want to damage the horn or plenum. Just think I'm missing something. Tried tapping it with a rubber mallet but no joy. Hopefully something easy that I just can't see. Thanks in advance for your help.

[We Gone]

Yes there is a gasket it may be just stuck from time, no sealer.

http://www.jerrysgaskets.com/gasket-...rn-90-95-11d6/

[A26B]

There are 4 bolts inside. Disregard the very small hole in the gasket.

[QMCMSS]

awesome help. I can see the other two will report back on progress. Thanks

[QMCMSS]

It's out new one on the way from Jerry's gaskets. Discovered a small oil leak looks like it's coming from the oil filter housing. Gonna check the forum to see if anyone has a similar issue and how to repair it.