cfjan

Stranded at the track today (was able to do 2 morning sessions, but missed the last 2) due to an alternator issue. A race mechanic there was nice enough to put a meter on the alternator and read only 11.8V, so it looks like it is shot.

Just curious how many of you guys have had to replace the alternator before? Is it a relative common problem?

Car only has 36k miles so it is not excessive.

Oh yeah, I really wish I have a trailer and a tow vehicle today.. big time!

DHI

Replaced mine.
Another unforgivable weakness of what was a $140,000 car.

I also lost a full day of track on account of it.

cfjan

Thanks for the quick response, Dave.. guess I am not the only one.. yeah, I just didn't expect something like this to go so early! For mechanical stuff, there's signs that you can predict the failure (such as noise, things are loose, etc.), but this just went without warning. I drove it to the track without problem in the morning and got stranded there in the afternoon! (Had to ask my brother-in-law to come pick me up, left the car at the track..)

DHI

What track were you at?

cfjan

Lime Rock.. ! About 1 hour and 20 minutes from home.

996FLT6

Have your starter checked too. These cars are old. Mike

cfjan

Mike, what's the signs for failing starter?

The goal is to just get the alternator working first, and then during the off season, drop the engine for the coolant fitting weld.. (and then do all the other stuff..)

85Gold

Very common problem. Almost always the regulator. Easy to pull out and any competent Alt repair shop can fix got well under $100.

Peter

cfjan

So the whole unit does not need to be changed? Is it a DIY? If it is, then I can try to repair it at the track so I can at least drive it home?

996FLT6

Rebuilding alternator and starter is cheaper than buying a new or rebuild one. Starter woes- it won't click and won't start. Get it done and no worries thereafter. Mike

85Gold

Alt is easy to pull just disconnect the battery 1st. I just remove and take unit to ALT repair shop. They usually have to order a regulator in which takes 1 to 2 days at least put here in the Stix.

Peter

StephenB

I would just go with a new one (not rebuilt). A Bosch AL0815N is a direct fit and has a freewheel pulley that helps keep your belt from flopping around. My 2004 did not have a freewheel pulley so I ordered the 2005 GT3 alternator which does. Amazon has them new for $250.

Steps to remove:
-Disconnect the battery
-Disconnect the electrical plug from the mass air flow sensor.
-Remove the complete air cleaner housing.
-Relieve the belt tension by turning the tensioner bolt (circled in yellow) clockwise and remove the belt.
-Remove the idler roller under the alternator (circled in green).
-Remove the left bolt (red arrow) from behind.
-Loosen the right bolt (circled in red) about three turns only
-Smack the bolt head squarely with your trusty copper BFH to loosen the steel bushing in the alternator housing, then finish removing the bolt.
-Carefully slide the alternator towards the rear of the car to gain access to the blue wire plug (note they leave almost no slack)
-Press the plug release towards the center of the alternator and pull off.
-Disconnect the B+ lead.

Takes about 1 hour to R & R.

85Gold

You do know that GT3,s run a lower charging voltage than most cars. I believe that are set around 13.8 to 14v max. Not sure if the above meets that criteria. If it does then it sounds like a good deal for a new unit.

Peter

cfjan

GREAT information, thank you! Already contacted my service shop about it since the car is still at the track, so maybe I will have to let them do the repair this time. But looks like something that I can do in the future.

Did I say that I need a towing setup!

996FLT6

Nothing beats arrive and drive. Money well spent!!! Mike