Background: Stock alternator lasted 68,000 miles, 160amp Eagle Auto (ebay rebuild) lasted 22,000. The consensus on here and the other sites is that the heat kills alternators and everyone's factory alternators seem to last the longest (aside from the $400 dollar plus options). This gives us two problems, new oem alternators are no longer in production and the mounting location is on top of the exhaust manifold. It's hard to change the location but a heat shield is possible, more on that, and new oem alternators are out there for cheap.
Tools Needed: Impact wrench (cheapo harbor freight), 9, 10, 13, 15, 23mm sockets, pryin' screw driver, sheet metal, tin snips, gloves, and eyepro
1. Sourcing the alternator (Thanks jrgoffin!): Two options Bosch and AC Delco make new 3.8 V6 alternators that are identical to ours aside from the pulley and post. The Bosch is the most expensive but has only a 12 month warranty and the AC Delco is the cheapest while it has 24 month warranty, your call either works. I went with the AC Delco below.
Why the V6 alternator
2. Converting the alternator: When the new one arrives you will notice the pulley is a small six rib and the post on the rear is oriented the wrong way. Follow the installation write up to remove your non working one Write up courtesy of doodad emphasis on removing the alternator bracket, it saves 30 minutes of grief over the loosen method :bowdown:. Don't worry the parts we need should still be just fine.
Once its out, prior to swapping posts.
Swapping the posts is pretty straightforward. I unbolted the 9mm nut under the red cap (visible on the old alt) and bolted my grungy, but correct, black post on the shiney new alt.
Now for the pulley.
While I liked the shiney new pulley, it obviously is too small for our cars so it had to go. Firmly grasp the pulley (while wearing gloves!) and give the pulley nut a quick blip with an impact wrench. I barely felt a tug on the pulley while doing this. I could not find a torque spec for the pulley nut or my strap wrench to hold the pulley with so I simply attached the nut with one blip of the torque wrench while holding the pulley, just like install.
Now we have a NEW OEM alternator for about $150. "But won't the heat just kill it eventually?" Yes it will thus step 3 make a heat shield.
3. Start with a cardoard mock up, it will be roughly triangle shaped fitting between the V of the motor and the fender. Installing from the bottom, the top will wrap over the top alternator bracket were it can be held by the top alternator bolt when you cut the real thing. The bottom should be even with the bottom of you oil filter.
Looking down at the top of the alternator and my mock up:
Once you have the real deal trace it on your sheet metal, my wifes paint roller pan made the ultimate sacrifice. It was steel but thin enough gauge to cut with tin snips by hand. WEAR GLOVES
Notice the bunny ears at the top, that's where the alt bolt goes holding your heat shield in place.
Key point, fold the fender side of your heat shield over to avoid nicking any of the rubber lines running along that fender with a jagged edge. I folded the bottom as well to make installation easier/safer. Install from the bottom, fold your rabbit ears over and clamp in place as you bolt the alternator down.
Those with actual fabricating skills will probably be able to build a much more substantial heat shield but I'm limited by tools and materials.
4. Add some cooling. I happend to have a brake duct kit from the previous owner (Thanks Dad!) that has sat on the shelf for the last 7 years so I put it to work. I used the supplied hardware to bolt it to the duct opening in the bumper then threaded the duct through the plastic fender liner bunching a much as possible in the engine bay and zip tying the opening to a coolant line next to the alternator.
Hope this helps everyone with their alternator woes!
Tools Needed: Impact wrench (cheapo harbor freight), 9, 10, 13, 15, 23mm sockets, pryin' screw driver, sheet metal, tin snips, gloves, and eyepro
1. Sourcing the alternator (Thanks jrgoffin!): Two options Bosch and AC Delco make new 3.8 V6 alternators that are identical to ours aside from the pulley and post. The Bosch is the most expensive but has only a 12 month warranty and the AC Delco is the cheapest while it has 24 month warranty, your call either works. I went with the AC Delco below.
Why the V6 alternator
2. Converting the alternator: When the new one arrives you will notice the pulley is a small six rib and the post on the rear is oriented the wrong way. Follow the installation write up to remove your non working one Write up courtesy of doodad emphasis on removing the alternator bracket, it saves 30 minutes of grief over the loosen method :bowdown:. Don't worry the parts we need should still be just fine.
Once its out, prior to swapping posts.
Swapping the posts is pretty straightforward. I unbolted the 9mm nut under the red cap (visible on the old alt) and bolted my grungy, but correct, black post on the shiney new alt.
Now for the pulley.
While I liked the shiney new pulley, it obviously is too small for our cars so it had to go. Firmly grasp the pulley (while wearing gloves!) and give the pulley nut a quick blip with an impact wrench. I barely felt a tug on the pulley while doing this. I could not find a torque spec for the pulley nut or my strap wrench to hold the pulley with so I simply attached the nut with one blip of the torque wrench while holding the pulley, just like install.
Now we have a NEW OEM alternator for about $150. "But won't the heat just kill it eventually?" Yes it will thus step 3 make a heat shield.
3. Start with a cardoard mock up, it will be roughly triangle shaped fitting between the V of the motor and the fender. Installing from the bottom, the top will wrap over the top alternator bracket were it can be held by the top alternator bolt when you cut the real thing. The bottom should be even with the bottom of you oil filter.
Looking down at the top of the alternator and my mock up:
Once you have the real deal trace it on your sheet metal, my wifes paint roller pan made the ultimate sacrifice. It was steel but thin enough gauge to cut with tin snips by hand. WEAR GLOVES
Notice the bunny ears at the top, that's where the alt bolt goes holding your heat shield in place.
Key point, fold the fender side of your heat shield over to avoid nicking any of the rubber lines running along that fender with a jagged edge. I folded the bottom as well to make installation easier/safer. Install from the bottom, fold your rabbit ears over and clamp in place as you bolt the alternator down.
Those with actual fabricating skills will probably be able to build a much more substantial heat shield but I'm limited by tools and materials.
4. Add some cooling. I happend to have a brake duct kit from the previous owner (Thanks Dad!) that has sat on the shelf for the last 7 years so I put it to work. I used the supplied hardware to bolt it to the duct opening in the bumper then threaded the duct through the plastic fender liner bunching a much as possible in the engine bay and zip tying the opening to a coolant line next to the alternator.
Hope this helps everyone with their alternator woes!
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