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Discussion Starter #1
Hi all,


This is likely a shot in the dark, but does ANYONE on here have the STOCK water pump, crankshaft AND alternator pulleys? My aftermarket ones are causing major drivability issues, to the point where the car is off the road and I will likely sell her if I can't get the factory pulleys. Please let me know!!
 

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Hi all,


This is likely a shot in the dark, but does ANYONE on here have the STOCK water pump, crankshaft AND alternator pulleys? My aftermarket ones are causing major drivability issues, to the point where the car is off the road and I will likely sell her if I can't get the factory pulleys. Please let me know!!


Just out of curiosity what is the problem that you think is related to the drive pullies?
Are you having a charging problem or an overheating problem? I have been running
underdrive pullies for a while now and the car doesn't run hot and charges fine.
 

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Hi all,


This is likely a shot in the dark, but does ANYONE on here have the STOCK water pump, crankshaft AND alternator pulleys? My aftermarket ones are causing major drivability issues, to the point where the car is off the road and I will likely sell her if I can't get the factory pulleys. Please let me know!!


Just out of curiosity what is the problem that you think is related to the drive pullies?
Are you having a charging problem or an overheating problem? I have been running
underdrive pullies for a while now and the car doesn't run hot and charges fine.
Stock alternator? No dim dash lights?
 

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You're issues are probably due to what Squekster alluded to?? If so,I never experienced any ill effects when I ran just a UD crank pulley with the stock alternator & water pump pulley.This,of course,will speed the alt & wp pulleys up a tiny amount,but not enough to notice. Therefore,if you can find the oem alt & wp pulleys,the ud crank pulley can probably be left in place,if you can't find the oem one or don't want the added expense.
 

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You're issues are probably due to what Squekster alluded to?? If so,I never experienced any ill effects when I ran just a UD crank pulley with the stock alternator & water pump pulley.This,of course,will speed the alt & wp pulleys up a tiny amount,but not enough to notice. Therefore,if you can find the oem alt & wp pulleys,the ud crank pulley can probably be left in place,if you can't find the oem one or don't want the added expense.
I ran the same on my fox. There weren’t really any charging issues, but the lights what dim. After replacing the little stock alternator w a 95 amp alternator it was better.
The 94/95’s have a 130 amp alt so you’ll prob be ok if you just ran an under-driven crank.
 

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However, once I read that the water pump and alternator pulleys that come with the u/d pulley kits are over driven pulleys. Meaning that they are actually sized to spin the accessories faster to compensate for the crank pulley. I don’t know if that’s accurate or not though.
 

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I believe the ud crank pulley is worth 5hp & the alt & wp pulleys make the additional 5hp,for a total of 10hp,thats standard for most pulley kits.I agree though,it seems like the alt pulley shouldn't bother anything seeings how the car came with a 130amp alt?? I wonder if the pulleys were installed recently or awhile back?? It seems like the problems would have popped up quickly after installation,if they were caused by the pulleys??
 

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Discussion Starter #10
Hi all,

So yes, these were installed by my mechanic after I got the car in the road in May. I noticed the issues right away, should've called him and had him look at it but didn't. He had my car for some other work for a few days, and after it sitting in my garage since November when I bought it, I just wanted to have it on the road and driving. Was hopeful the issue would resolve itself ( ya right) but then did some research and actually saw that most UDP kits make the pulleys drive SLOWER than normal, hence an alternator that doesn't charge the battery the way it should. Saw this on a thread somewhere in this forum, I believe. My battery meter starts dropping below 13ish volts as my RPMs fall, in Drive only. In park it could probably run until it runs out of gas. No dim lights or anything. But any sort of pull on the battery definitely makes the meter drop more quickly and significantly. It sucks, I have to literally put the car in neutral and rev her some to prevent it from stalling out at red lights or in traffic.
 

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Hi all,

So yes, these were installed by my mechanic after I got the car in the road in May. I noticed the issues right away, should've called him and had him look at it but didn't. He had my car for some other work for a few days, and after it sitting in my garage since November when I bought it, I just wanted to have it on the road and driving. Was hopeful the issue would resolve itself ( ya right) but then did some research and actually saw that most UDP kits make the pulleys drive SLOWER than normal, hence an alternator that doesn't charge the battery the way it should. Saw this on a thread somewhere in this forum, I believe. My battery meter starts dropping below 13ish volts as my RPMs fall, in Drive only. In park it could probably run until it runs out of gas. No dim lights or anything. But any sort of pull on the battery definitely makes the meter drop more quickly and significantly. It sucks, I have to literally put the car in neutral and rev her some to prevent it from stalling out at red lights or in traffic.
Yeah man, Underdrive pulleys are kinda bunk. You could get a higher amp alternator I guess, but it would probably be more expensive than replacing the pulleys and you won’t really notice any loss in speed.
Did you ever have it running with the stock pulleys? The stalling could be another issue but they aren’t helping the matter for sure.
*Edit*
In a nutshell under-drive pulleys slow down the accessories so they can “free up” power to the crank. How much power? Probably not enough to change the outcome of a race.
 

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These guys,in my neck of the woods, might have some stock pulleys too.They sell & install performance parts,do supercharger/turbo installs,do engine swaps,do dyno & tuning work & they also sell used parts off of wrecked/salvaged Mustangs.Their wrecked/salvaged inventory is constantly changing,so you'll
have to call to see if they can help you or not.

Delk Performance Parts & Service

https://www.ebay.com/str/delkperformanceparts
 

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Discussion Starter #13
Thank you all. I drove it before installing the pulleys and had no issues. Just kind of a bummer, I should've done more research into them. Thanks for the link to delk performance!
 

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If you can get the part number for each oem pulley you need,you might be able to cross reference each one to other Ford models with the same pulleys,that way you'll have a bigger selection if you decide to get the parts at Pull-A-Part.Its very rare to see 85-93 5.0 and 94-95 5.0 Mustangs at Pull-A-Part,but the 3.8 models & other Ford models with the 302 are normally available.I don't know if the Non HO 5.0 cars have correct pulleys or not for the sn95?? Probably not.
 

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Here's a list of Ford's BASIC part numbers for the pulleys. Keep in mind that these are merely partial part numbers, and should be preceded with something like "F4ZE" or "F4ZZ".
8509 - water pump pulley
10344 - alternator pulley
8678 - idler pulley
3A733 - power steering pump pulley
2E884 - A/C clutch pulley
6312 - crankshaft pulley
9B447 - secondary ait injection pump pulley
6B209 - tensioner
 

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Here's a list of Ford's BASIC part numbers for the pulleys. Keep in mind that these are merely partial part numbers, and should be preceded with something like "F4ZE" or "F4ZZ".

:goodpost
 

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Discussion Starter #17
Thanks to you guys both! Wbrockstar, you and I had a mindmeld, I had that exact thought earlier today. And I amazingly might have come across OE spec replacement pulleys at Summit ! Called technical support earlier but couldn't reach anyone. Going to try again tomorrow.
 

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Discussion Starter #18
Hi all,


I feel very blessed right now...just found the EXACT replacements (Crank, Water Pump and Power Steering) in Good used condition, OE, from a guy in Kansas. Thank God for eBay! Purchased them as soon as my keyboard would let me hit "send", haha. I will keep you all posted, praying all will go well!
 
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Hi all,


I feel very blessed right now...just found the EXACT replacements (Crank, Water Pump and Power Steering) in Good used condition, OE, from a guy in Kansas. Thank God for eBay! Purchased them as soon as my keyboard would let me hit "send", haha. I will keep you all posted, praying all will go well!
Good score
 
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