Delco alternator not happy at temperature!
#1
Rennlist Member
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
The Delco alternator conversion works great until things get heavy (load that is) and hot.
So I figured the first thing to do is to get it spaced out from the engine block!
The extensions are 1" x 1/8" from Home Depot. I used a grinder to round off the end by the timing belt to give lots of clearance. I also used a spacer of hollow round that this a bit more than 8mm for the original mounting point.
This extends it 24mm.
Perfect fit!
Now the distance from the top to bottom mounting points are same as the original.
I used the smaller belt I bought for the original Delco conversion.
I expect to buy a belt 1 1/2 to 2" longer to move it out more.
I also used wider (as opposed to thicker) washers with smaller holes to clamp either side of the alt wire B+ as the lug hole was much larger than the stud.
Next will be a cooling shroud if needed.
So I figured the first thing to do is to get it spaced out from the engine block!
The extensions are 1" x 1/8" from Home Depot. I used a grinder to round off the end by the timing belt to give lots of clearance. I also used a spacer of hollow round that this a bit more than 8mm for the original mounting point.
This extends it 24mm.
Perfect fit!
Now the distance from the top to bottom mounting points are same as the original.
I used the smaller belt I bought for the original Delco conversion.
I expect to buy a belt 1 1/2 to 2" longer to move it out more.
I also used wider (as opposed to thicker) washers with smaller holes to clamp either side of the alt wire B+ as the lug hole was much larger than the stud.
Next will be a cooling shroud if needed.
#2
Chronic Tool Dropper
Lifetime Rennlist
Member
Lifetime Rennlist
Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I'm not sure you can get the alternator low enough with those spacers.
It needs to be in a cool air stream, not swallowing the hot air that's passed through the AC condenser and the radiator. Heat conduction through the bracket from the block isn't nearly as big a factor as trying to cool the alternator with 200º+ airflow. The cooling hose and shroud make a huge difference.
Enough folks are doing the Delco and Motorcraft replacements that there's an emerging market for a vacuum-molded plastic shroud with a hose schnozzle on the back. Did any GM cars (Corvette??) duct cool air to their alternators?
![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
Enough folks are doing the Delco and Motorcraft replacements that there's an emerging market for a vacuum-molded plastic shroud with a hose schnozzle on the back. Did any GM cars (Corvette??) duct cool air to their alternators?
#3
Rennlist Member
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
It is not the heat conducted from the block I am worried about, it is that it is tucked in so close that you can't get a shroud around it.
So I moved it out.
Now more room.
The power lug is also a big problem. It's diameter is way too big. Hopefully the wide washers with smaller diameter holes will increase the contact area of the lug to post.
BTW the harness is 928 Motorsportd so not sure if the hole is stock.
So I moved it out.
Now more room.
The power lug is also a big problem. It's diameter is way too big. Hopefully the wide washers with smaller diameter holes will increase the contact area of the lug to post.
BTW the harness is 928 Motorsportd so not sure if the hole is stock.
#5
Rennlist Member
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I figure the way the fan spins, it is sucking air out from the back.
I bought a cheap alternator from Autozone.
I'm thinking get one with the lifetime warranty.
Maybe better quality?
Making a shroud looks like a tough proposition.
I bought a cheap alternator from Autozone.
I'm thinking get one with the lifetime warranty.
Maybe better quality?
Making a shroud looks like a tough proposition.
Last edited by LT Texan; 07-05-2013 at 09:57 PM.
Trending Topics
#8
Rennlist Member
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I'm gonna pick up another alternator today and see if that is my problem.
Maybe it's a crappy one. Maybe it's toast. Maybe too much power steering fluid in it?
Maybe it's a crappy one. Maybe it's toast. Maybe too much power steering fluid in it?
#10
Rennlist Member
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
All new "Gold" Duralast from Autozone $109.99. Looks better all around.
Special order item, but got free 1 day shipping and a $25 reward card!
$10 core on the old one.
Special order item, but got free 1 day shipping and a $25 reward card!
$10 core on the old one.
#11
Drifting
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
And virtually impossible on the motorcraft.
FWIW, the motorcraft I put on my '85 is frequently used on transverse mounted engines, and placed between the firewall and the engine, right next to the exhaust manifold. Ford clearly wasn't worried too much about heat, so I won't worry much either.
FWIW, the motorcraft I put on my '85 is frequently used on transverse mounted engines, and placed between the firewall and the engine, right next to the exhaust manifold. Ford clearly wasn't worried too much about heat, so I won't worry much either.
#13
Rennlist Member
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Aircon, headlights and radiator fan all on, the Autozone Gold Duralast is showing just under 12 on the voltmeter at highway speed. (Temp in the 90's.)
I usually get 1 to 1 1/2 more volts reading at the jump post.
In the Texas heat of 105F, the volts read lower than when the temps were in the 90's.
I found that my radiator fan needs to be on to keep it cool at highway speeds. That doesn't seem right. I'll have to see what's going on with that. (PO cut out a hold in the top radiator shroud so air can go through it.
)
Wondering if replacing the battery cables would make a difference? Engine wiring harness is about 5 years old, so that should be fine.
Hate the voltage drop from the engine compartment jump post to the voltage gauge.
I think I'll take the advice to wire the electric fans (dual Taurus) directly to the positive cable at the starter.
I usually get 1 to 1 1/2 more volts reading at the jump post.
In the Texas heat of 105F, the volts read lower than when the temps were in the 90's.
I found that my radiator fan needs to be on to keep it cool at highway speeds. That doesn't seem right. I'll have to see what's going on with that. (PO cut out a hold in the top radiator shroud so air can go through it.
![Mad](https://rennlist.com/forums/images/smilies/mad.gif)
Wondering if replacing the battery cables would make a difference? Engine wiring harness is about 5 years old, so that should be fine.
Hate the voltage drop from the engine compartment jump post to the voltage gauge.
I think I'll take the advice to wire the electric fans (dual Taurus) directly to the positive cable at the starter.
#15
Rennlist Member
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Just seems to be too much voltage drop and I don't know why. Grasping for straws.
At a stoplight, idling, lights on, defroster on, wipers on, rad fan on, stoplights on - deep in the red.
It all worries me.
At a stoplight, idling, lights on, defroster on, wipers on, rad fan on, stoplights on - deep in the red.
It all worries me.