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which DP vendor has the correct 6.5L alternator

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5.2K views 26 replies 7 participants last post by  jnlperformance  
#1 ·
1994 6.5.... gonna order my new alt...

lookin for correct pulley size (66mm?)

not lookin for huge amperage.... stock 105/110 amp will be sufficient for now
 
#2 ·
62mm

Bought my alt from oh really for $100 LT Warranty.... easier to warranty stuff you need now to make the truck go Vroom than through the mail. Just my opinion. Mail order I do stuff like body parts filters etc.
 
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#3 ·
#4 · (Edited)
#5 · (Edited)
Stock Alt (CS130) is undersize in terms of capacity at idle rpm, it only gives around 20-30 amps at idle.
The max number is immaterial (105 amps). Plus it tends to heat up due to the size of the casing.

If you have a chance and need to change it, get CS144 or AD244 alt.

CS144 is a more popular choice since it is an option with 96+ model year.
AD244 is used after 2000 model year and it is thinner same diameter as CS144 and I have put it in my truck with minor mod.

These alt gives around 60-70 amps at idle and can keep up with most of the standard accessories like headlight, radio, AC, etc.

Price wise, not much difference but you need to modify the bracket a little bit.
 
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#7 ·
By the way, if you want the right pulley, you may have to go to a local rebuilder and let them put in the correct pulley.

There is no DP vendor selling alternator, at least not that I know of.
 
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#10 · (Edited)
i think im beginning 2 understand the issue. i just bought a new alt. measured 62mm diameter across the face.

ill take some piks.

if i stick with this alt, put on correct pulley - ill get less amps then im getting now because smaller = faster.

im going 2 install it, see what happens. i need a new alt for sure, but i want it to work right, and i want a true reading @ dash, otherwise why have a tach? i can do the math on the fly but that gets old and im a perfectionist anyway....

so if I upgrade to a cs144, install correct pulley, likely ill get correct apmerage and rpms@tach??

I have a 120A fuse breaker between alt and battery right now. If I upgrade to cs144 what fuse rating do I need (after correct pulley install)
 
#11 ·
Remove the correct pulley Off the bad alternator and install it on the new unit. 1/2" impact will zip the nut off and easily.
 
owns 1985 GMC Sierra 6.2 K3500 SRW Manual
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#12 · (Edited)
pulley I have on now is incorrect.


cs144 pulleys
http://store.alternatorparts.com/partno241281.aspx - correct pulley??
http://store.alternatorparts.com/cs144-series-alternator-pulleys.aspx - larger list of pulleys

larger list of pulleys.
http://store.alternatorparts.com/6-groove.aspx

here is a pik of alt i bought last night. cheap pos. it does not turn freely. gets caught up in certain spot (should return anyway??)

www.dieselplace.com/forum/members/m...2mm-diameter-across-face-pulley-56-57mm-across-belt-grooves-incorrect-size.html - pik of new alt from last night
 
#14 · (Edited)
morning fred, gonna take it back.

i just want a quality alternator... thats not going 2 require mods 2 put in... while fixing my rpm and tach issues.

ive got enough amps. voltage regulator is bad in one I have now.

will that cs144 bolt in w/o mods? does it come with friggin correct pulley? lol

also, I have a 120A fuse for alt... with cs144 is that enough? or will it need to be larger? 150A 200A 220A...ect
 
#16 ·
Good morning, Michael.

Toss up on buying a good quality, more expensive alternator like AC Delco, etc or one from the local parts store with a lifetime warranty where it is much easier to return.

I bought mine from Advance Auto. Lasted 2 weeks before one of the bearings/bushings failed and the "fan" dug into the housing.....but I got another one for free and within an hour had it replaced. Had it for a year and so far so good. But I can see on the volt meter the draw down with heat blowing and the lights on......I am not sure how healthy that is for the batteries.
 
#17 · (Edited)
yea thats my concern if this were any of my other rides I wouldnt care... but @ double the cost of the alternator (batteries).... yea... no point in that there either.


ur right i guess... its a crap shoot.

how about those pullies? which one is the one I need to order??

21x61x7 x6 groove?

ill just get correct pulley and stick with a crap autozone alt for now. f-it.
 
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#18 ·
Other than getting the nut off which is easy with an impact I have never had a problem getting the pulleys off alternators. Many seem to just pull off, others you just tap em a few times with something small like a screwdriver handle and they then pop off. I always expect to have to fight em but so far they come off.
 
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#20 ·
Starters, Alternators and more for Cars, Trucks, Tractors and ATVs

AWESOME. ok... so I just got off the phone with these guys. all they do is starters and alts... got me the correct pulley. 21mmx61.2mmx17mm

got some good alternators and starters from the looks of it...

got it shipped same day air... ill post results 2morrow...
 
#22 ·
just gonna stick with my brand new pos duralast - freddy im with ya on the warranty... their issue if its no good.

if it damages anything... ill MAKE it their issue.

otherwise correct pulley is on the way. ill be seeing it 2morrow or day after. sometime this week at least.

as stated ^^^... ill post results.
 
#24 ·
im gonna exchange this alt for a different one tho, I dont like how it seizes up on that particular spot. the "new" one from oreillys did the same... unless this is common?

i had spun a remanned unit... did better... no seizing ... should I get that one??
 
#25 ·
ok, as far as advance auto, autozone and oreillys its a crap shoot for the correct pulley size. ive bought 4 new alts. ive returned 3. kept the one from napa seeing as how it came with the correct pulley.

for those who are looking for the CORRECt OE 100-105amp alternator replacement with the CORRECt pulley (the common 9mm offset type) .... napa part # 1N-4555D. 132 dollars and some change. brand new alternator. turns great, no seizing up while turning by hand.

that dbelectrical.com place in tn... they are crap and sent me the incorrect pulley even after i had sent them a diagram with precise measurements.

i did manage to find a place around town that had an original stamped pulley. apparently there are 2 different pulleys? one with a 9mm offset/spacer deal and one with a 14mm. i already have 2 of the 9mm offset (the stamped one i snagged here in town and the turned one that came on the napa alt) but I told the guy to order me the 14mm offset.

gonna try the 14mm offset as well - used a stright edge as another thread mentioned. it would seem that my alt pulley is 14mm too far back, and needs to move forward a bit and would be the answer to my fraying belt ...

so i guess im fixing three or 4 issues at once here.
-low ign voltage
-damaged volt regulator
-incorrect tach reading
-fraying belt and offset pulley by 14mm. go figure.


who would have known an alternator would have been such a pain in the arse!

ill take some piks of old alt, new alt... some pulleys side by side...
 
#26 ·
michaelogan said:
the CORRECt OE 100-105amp alternator replacement with the CORRECt pulley (the common 9mm offset type) .... napa part # 1N-4555D.
Click to expand...
Napa Online shows my store @ $125 and save 10% off, through the 25th of Feb if you reserve online and pickup in your local store.
 
owns 1985 GMC Sierra 6.2 K3500 SRW Manual
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