Newbie Alternator and Belt Change Instructions

[66DartSedan]

Since this is my first car, people are telling me not to change the belt and alternator myself as they think the belt needs to be put on my pro.

But the belt looks dry rot so I'd like to upgrade and it looks pretty simple to me. No? Am I too ambitious?

Can anyone give me a step by step guide to changing my alternator and power steering belt on my 66 Dodge Dart and also tell me what Amp you think my current one is? the stamping says #4111973 #46264

Thanks!

 

[krazykuda]

The bolt on the top bracket that has the slot in it is the adjustment... there is a long bolt opposite of that which is the "pivot"...

Loosen both the pivot bolt and the slot bolt and enough so you can move the alternator inward and remove the belt... The pivot bolt should be 9/16" and the adjusting bolt should be 1/2"... Be sure to look at the routing of the belt to see what pulleys it goes on or get some good pictures at different angles so you can refer to them later...

Then remove the belt from the engine, taking it off carefully... It is sometimes helpful to rotate the fan to get the belt out from under it while removing it... Likewise rotate the fan to get the new belt on...

Place the new belt on the crank pulley, then the water pump/fan pulley, then lastly get it over the pulley on the alternator...

Then pull hard on the alternator or use a pry bar for leverage to tighten the belt to where there is less than 1/2" of flex in it... Tighten the adjusting bolt on the slotted bracket first, then the center pivot bolt opposite...

Test the tightness of the belt by pushing on a fan blade and see if the whole motor cranks over (if it's got some miles on it and is loose) or is the belt slipping??? If the belt is slipping, then tighten it a little more... if it wants to turn the engine over by pulling on a fan blade of a non-clutch fan, then it's tight enough and you're good...


The belt will stretch slightly and loosen a bit after it breaks in for about 10 - 30 minutes, so check it after you run it for a while to make sure it's still tight...


You can do it...

 

[tonysrt]

If you have a set of wrenches, open end or box and a socket set your good to go. All bolts are standard American not the pathetic metric size. Buy the right size belt and make sure it is the right size by putting next to old belt before you take it apart. There are 2 bolts you have to loosen to move alternator toward the fan to remove old belt. Those bolts are 1/2" and 9/16". Install new belt on the same pulley you took old from. You'll also have to loosen the power steering pump to get Alt. belt off and back on. You may as well replace the Power steering pump belt while you're in there. When tightening Alt. belt have about 1/2" play at the middle of long run between the two pulleys. If belts howl when you run engine up tighten belt a little more. This is probably the easiest job you'll ever get to do. Good luck and make sure bolts are tight when reinstalling everything.

 

[krazykuda]

I see you also have power steering... The power steering belt is in front of the alternator belt on the crank pulley and must be removed first before you can get the alternator belt off...

The power steering belt is the same, just loosen the bolt on the curved slot (adjustment) then loosen the pivot bolt opposite and remove the belt...

Then change the alternator belt and put the power steering belt on after... You may as well get a new power steering belt since you have to remove the old one anyway to get to the alternator belt...

 

[krazykuda]

Since this is my first car, people are telling me not to change the belt and alternator myself as they think the belt needs to be put on my pro.

But the belt looks dry rot so I'd like to upgrade and it looks pretty simple to me. No? Am I too ambitious?

Can anyone give me a step by step guide to changing my alternator and power steering belt on my 66 Dodge Dart and also tell me what Amp you think my current one is? the stamping says #4111973 #46264

Thanks!

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From looking at the first picture, there is a "square back" alternator on that and 66 should have a round back...

It is a single field wire set-up on that so your car should have the old solid state voltage regulator mounted on the firewall...

As long as it works, you're ok, but if it you want to get back to the original style, look for a roundback...

There is a place locally near me that rebuilds them and can upgrade the amps if you want also... They do a good job and make their own windings - not that Mexico/China crap... If you need a rebuild call and send it to them before trying the parts store junk that is bad right off the shelf...

P&G Keene Electrical Rebuilders LLC

Edit: You also have a double pulley on the alternator, it will work, but a single pulley will be better lined up with a non A/C car... If you change the alternator, bet a single field with a single groove pulley in whatever amperage you want/can get...

A/C cars had double groove pulley alternor & belts...

Non A/C or heater only cars had single groove pulley alternators and one belt...

 

[66DartSedan]

From looking at the first picture, there is a "square back" alternator on that and 66 should have a round back...

It is a single field wire set-up on that so your car should have the old solid state voltage regulator mounted on the firewall...

As long as it works, you're ok, but if it you want to get back to the original style, look for a roundback...

There is a place locally near me that rebuilds them and can upgrade the amps if you want also... They do a good job and make their own windings - not that Mexico/China crap... If you need a rebuild call and send it to them before trying the parts store junk that is bad right off the shelf...

P&G Keene Electrical Rebuilders LLC

Thanks, i didnt know that wasn't OEM...do you think this is 50 amp? 60amp? Is there a way to tell?

 

[Steve 225]

I'd add . The bolts look a little rusty, may be a good idea to give them a shot of WD40 or something similar, and just to be on the safe side take off the positive battery cable before you start so you don't accidentally ground out the alternator which you probably won't or can't, but sometimes a wrench slips
It's a 60s slant 6 and you don't have AC in the way it should be real simple

 

[krazykuda]

Thanks, i didnt know that wasn't OEM...do you think this is 50 amp? 60amp? Is there a way to tell?

The best way is to take it off to a parts store and have them test it... However, I found the employees at my local Auto Zone do not know how to hook it up to the machine properly and can't do a fair test... P&G Keene fixed the old core that we hadn't turned into Auto Zone when we got the defective new one and was able to test it properly and verify our new rebuild was good and the parts store one was junk...

I doubt it was a 60 amp from the factory as most of them didn't have too many electronic options...

Here's a alternator spec chart from the 66 Dodge Dart service manual.. If you don't have a copy of the service manual, go here and get a free download, start out with the 66 Dodge Dart and Coronet service manual:

MyMopar - Mopar Forums & Information - Service Manuals

 

[66DartSedan]

The best way is to take it off to a parts store and have them test it... However, I found the employees at my local Auto Zone do not know how to hook it up to the machine properly and can't do a fair test... P&G Keene fixed the old core that we hadn't turned into Auto Zone when we got the defective new one and was able to test it properly and verify our new rebuild was good and the parts store one was junk...

I doubt it was a 60 amp from the factory as most of them didn't have too many electronic options...

Here's a alternator spec chart from the 66 Dodge Dart service manual.. If you don't have a copy of the service manual, go here and get a free download, start out with the 66 Dodge Dart and Coronet service manual:

MyMopar - Mopar Forums & Information - Service Manuals

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I ordred a single pulley 50amp from rock auto hoping to get "more" for my electrical system but you say its most likely not OEM and since it has 2 pulleys probably already 60 amps? I think it works fine now, but Im just trying to replace all the parts since I bought the car. He had it sitting a lot.
I may need to return my 50amp alt

 

[krazykuda]

I ordred a single pulley 50amp from rock auto hoping to get "more" for my electrical system but you say its most likely not OEM and since it has 2 pulleys probably already 60 amps? I think it works fine now, but Im just trying to replace all the parts since I bought the car. He had it sitting a lot.
I may need to return my 50amp alt

If you put a double pulley alternator instead of a single pulley alternator, the single groove pulley is in the center of the two, so it is not perfectly aligned... It will work, but there will be more side load on one side of the belt and it will wear unevenly in the long run... You have to match the alternator pulley with the other pulleys on the car...

 

[RedFish]

I did not find "disconnect negative battery cable" in any above post. Factory service manuals are free downloads.

 

[krazykuda]

Never mind...

 

[66DartSedan]

If you put a double pulley alternator instead of a single pulley alternator, the single groove pulley is in the center of the two, so it is not perfectly aligned... It will work, but there will be more side load on one side of the belt and it will wear unevenly in the long run... You have to match the alternator pulley with the other pulleys on the car...

Thanks, I ALWAYS detach my positive and negative terminals from my battery before I touch anything on my car. perhaps its overkill, but as a beginner, i dont have $ for mistakes. I guess Im going to need to have the alternator checked for how many amps is running because I recently bought and installed an electronic voltage regulator from @furygt on ebay: Mopar Voltage Regulator - Electronic Solid State with Correct Restoration Look | eBay

And it specifically stated NOT to use an alternator above 65 Amps. So IF my squareback alt is not OEM and the last guy put it on, say its running 75amp for all I know, it could damage the Ext voltage regulator no? Also that could be why my , oil gauge, temp gauge and gas gauge aren't working, maybe that blew them?

 

[Dave Haertel]

I would add, check your alignment with the belt and the alternator after it's installed. I have an AC car but they stripped the compressor before I got it so I have a double pulley alternator but no compressor. My alignment of the belt/alternator goes out constantly because I still need to replace all the brackets. Not only does it look goofy and is immediately noticeable, it wears the belt early AND it squeaks like a son of a *****, literally driving me batty. It works so I'm still fixing things that don't work but that is definitely something I want to get to soon lol.

 

[tonysrt]

In your first post you didn't mention that you were having charging problems. You did mention changing alt. & belt. The poor shape of that belt could be the reason for charging problems. Under load, the Alt. belt could be slipping causing the no charge problem. When having a problem try to give as much info so the minds here can get to the root of the problem and make suggestions to help you.

 

[BillGrissom]

No fear. Changing a slant six "fan belt" is one of the easiest jobs. As mentioned, you must remove the p.s. belt which is harder, and best to change it too since belts cost ~$5 on rockauto. You should see how tough it is to loosen the alternator on my 1980's M-B cars (designed by drunk Germans). Keep a spare belt in the trunk. For roadside emergency, you could cut off the p.s. belt and leave it off (p.s. is only needed in parking lots). In emergency, main thing is to keep the water pump and fan spinning, which you can do w/ nylon rope. In an old car, you can drive ~200 miles off the battery if no headlights.

I would use the later square-back alternator like you have, since it gives more output, esp. at idle. You simply need to ground one field terminal, which it appears was done in your old one. You might also change to an electronic voltage regulator for 1966 (rockauto). Many posts.