1979 MY Alternator shroud - Update - trying to make it fit!
#16
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While on this subject of the cooling duct. The duct directs cool air through the alternator from the back and the fan directs air from the front. So what we have is a stand off,ie no airflow through the alternator. Also with the fan on everyones alternator the vanes are pushing air radially to the front face and not scooping air and forcing it through the alternator body. If the fan was turned around it would scoop air and draw it forward out of the alternator assisted by the pressure from the flow the shroud provides. Anyone have any explanation or other theory?
As it it is designed, the fan is pulling air through from the back/shroud/hose and extracting it through the fan vanes - and no way for the fan vanes to ingest crud.
#17
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I have obtained the stainless threaded rod - Google was my friend! The stock bolts are M5 x .8 thread. I found a meter of threaded rod stock locally for $4 out the door and have a fist full of nuts, washers and lock washers so next steps are to take the alternatior apart and give it a good cleaning.
I will add pictures as I get a chance.
Thanks for the recommendations.
I will add pictures as I get a chance.
Thanks for the recommendations.
#18
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BRB-83-911SC
If the vanes were to scoop air, they would be pushing air in from the front and out the back, and all the crud the vanes would pick up as well - opposite of intended design.
Brian
If the fan is turned around it will scoop air out of the alternator.The way it is now it just paddles away with no direction since the back of the vanes are bent the wrong direction for rotation.
And as for crud I just cleaned 1/2" of sand, oil, leaves , maple keys and bugs from the shroud and back of the alternator. So, so much for the no crud theory.
My alternator also had additional tapped holes in the rear casting to accomodate the allen drive capscrews that held the shroud on.
If the vanes were to scoop air, they would be pushing air in from the front and out the back, and all the crud the vanes would pick up as well - opposite of intended design.
Brian
If the fan is turned around it will scoop air out of the alternator.The way it is now it just paddles away with no direction since the back of the vanes are bent the wrong direction for rotation.
And as for crud I just cleaned 1/2" of sand, oil, leaves , maple keys and bugs from the shroud and back of the alternator. So, so much for the no crud theory.
My alternator also had additional tapped holes in the rear casting to accomodate the allen drive capscrews that held the shroud on.
#19
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The vanes act as a centrifugal blower, pulling air in from the rear of the alternator and exhausting it radially at the front. A smoke test will show the air flow clearly.
As the cigarette butts that show up on the intake air filter show, crud can get from the road, thru the grille, thru the air intake tubes, and on top of the filter. The bend in the intake hose on the alternator cooling system helps, but it is not a filter.
As the cigarette butts that show up on the intake air filter show, crud can get from the road, thru the grille, thru the air intake tubes, and on top of the filter. The bend in the intake hose on the alternator cooling system helps, but it is not a filter.
#20
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The vanes act as a centrifugal blower, pulling air in from the rear of the alternator and exhausting it radially at the front. A smoke test will show the air flow clearly.
As the cigarette butts that show up on the intake air filter show, crud can get from the road, thru the grille, thru the air intake tubes, and on top of the filter. The bend in the intake hose on the alternator cooling system helps, but it is not a filter.
As the cigarette butts that show up on the intake air filter show, crud can get from the road, thru the grille, thru the air intake tubes, and on top of the filter. The bend in the intake hose on the alternator cooling system helps, but it is not a filter.
#21
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if you have the bend in the hose, behind the wheel liner, you should not need a screen. one thing you could do, is where the hose goes over the plastic "snout", you could slip over some pantyhose first, then the hose. i used a similar trick on a cold air pick up on my cummins.
#22
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You could go to your local parts store and look for an old-fashioned valve cover cap - the type that serves as a crankcase vent and place to add oil. Mount it to the end of the hose so it doesn't rattle or fall off.
#23
Three Wheelin'
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My 81 came with an Audi alt according to my alt/starter guy. Looked just like that one, I ruined a shroud trying trying to adapt it. I'd like to see a solution to this.
#24
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So I replaced the bolts with threaded rods and attached the shroud but of course I have clearance issues between the back of the schroud and the engine![banghead](https://rennlist.com/forums/graemlins/banghead.gif)
Tomorrow I will try and figure out where the conflict is and see if I can cut down the schroud to allow it to fit.
Nothing is ever easy!
![banghead](https://rennlist.com/forums/graemlins/banghead.gif)
Tomorrow I will try and figure out where the conflict is and see if I can cut down the schroud to allow it to fit.
Nothing is ever easy!
#25
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So I replaced the bolts with threaded rods and attached the shroud but of course I have clearance issues between the back of the schroud and the engine![banghead](https://rennlist.com/forums/graemlins/banghead.gif)
Tomorrow I will try and figure out where the conflict is and see if I can cut down the schroud to allow it to fit.
Nothing is ever easy!
![banghead](https://rennlist.com/forums/graemlins/banghead.gif)
Tomorrow I will try and figure out where the conflict is and see if I can cut down the schroud to allow it to fit.
Nothing is ever easy!
#27
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So after trying multiple combinations all day in between stoking the smoker for the pulled pork I realized two things. I want to shoot myself and I have never seen a shroud and hose on a car to know how it should be oriented relative to the alternator and the car structure.
Where should the shroud tube sit relative to alternator and car?
Where should the shroud tube sit relative to alternator and car?
#28
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At least you figured out how to spell shroud. That was bugging me.![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
I'm going to have the same problem when I replace mine, which is missing. If you or anyone can get a pic it would be great.
![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
I'm going to have the same problem when I replace mine, which is missing. If you or anyone can get a pic it would be great.
#29
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Here are a couple of pictures of an installed alternator with the cooling shroud. The second is from the passenger side of the car (USA) looking at the side of the alternator. The first is from the back of the engine looking forwards.
Please let me know if you need additional pictures as the car is still on the hoist.
Note that the 86.5 alternator shroud is very close to identical (hose is just run slightly different).
Glenn
Please let me know if you need additional pictures as the car is still on the hoist.
Note that the 86.5 alternator shroud is very close to identical (hose is just run slightly different).
Glenn
#30
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Here are a couple of pictures of an installed alternator with the cooling shroud. The second is from the passenger side of the car (USA) looking at the side of the alternator. The first is from the back of the engine looking forwards.
Please let me know if you need additional pictures as the car is still on the hoist.
Note that the 86.5 alternator shroud is very close to identical (hose is just run slightly different).
Glenn
Please let me know if you need additional pictures as the car is still on the hoist.
Note that the 86.5 alternator shroud is very close to identical (hose is just run slightly different).
Glenn
![bowdown](https://rennlist.com/forums/graemlins/bowdown.gif)