DeTomaso Mailing List: March 2001, Message #133

Hack,

Thanks so much.  Your letter puts together all the great advice that's been 
coming in.  I don't race or ever rev past 6000rpm on the engine, so I'm 
safe setting the alternator for a higher drive ratio.

My choices are to;
1.  Use a smaller pulley on the same ribbed  belt system, but would require 
an idler pulley to keep the tension and to keep the alt pulley from slipping.
2.  Use a two belt system.  Move the alternator rearward to its original 
position, and add a larger drive pulley on the dampener, add a stock (which 
is smaller) driven pulley to the alt.
3.  Suffer with what exists now.  Its fine in the winter anyway.

Right now I'm going for #2, and need to shop for pulleys.  I successfully 
removed the 15/16'ths bolt from the dampener.  A friend encouraged me to 
use a cheater bar while he stood on the brake pedal.  Using a 3' lever arm, 
I turned the bolt loose.

The bolt had silicone sealer on it, and oil drips out of the hole!

I then took the rubber mallet and banged the pulley off.  To my 
embarrassment, it was not restrained by the bolt after all.  (I didn't 
listen.) :-(  It seems the oil and dirt made it all look 
continuous.  Cleaning it up, the pulley is aluminum and the dampener is steel.

So, now I am shopping for pulleys, this is good.  I am also wondering how I 
opened pandora's box.  Is it normal for oil to flow out of the  bolt hole 
in the middle of the dampener?  What is the "normal" procedure for 
re-installation?

You folks are great!

Mike (need some bathtub calking) Royer


At 07:04 AM 3/4/2001 -0800, Hack D. Carsome wrote:
>Mike
>
>A photo is worth a thousand words.  Great photo.  Your set up is 
>aftermarket right?  Haven't seen this before.
>Some thoughts:
>
>Larrs was right - the alternator amp rating is at 1800 to 2300 rpms 
>(alternator rps) or so depending on the manufacturer.  At idle it's not 
>getting there.
>
>Gary Hall has a variation on what you have.  He sells a gilmer (cogged) 
>belt drive system based on a similar 4 pully config.
>
>I think we all struggle with the alternator keeping up at idle.  And it 
>gets worse with bigger radiator fans and A/C fans.  I know I have 
>struggled with it with my stock v belts.
>
>I think the core root issue is the diameter of the drive pulley.  It is 
>5.5 inches (Stock) where as most of my other non-italian exotic go fast 
>cars are 6.5-6.75 inches.  I'm not positive but I think Gary's Gilmer deal 
>has a larger diameter drive pully.
>
>And of course realize that at 6500 rpm's (engine rpm) the alternator 
>bearings will be spinning 13000 rpms ect.  So it is a two edged sword, 
>spin faster at idle, cook the alternator when racing.
>
>So the advice is:
>
>Turn your idle up to 800-1000 and struggle
>or
>Drive faster
>or
>Have a new drive pully fabbed (check clearance between the pully and the 
>body, I know a larger v-belt pulley would require cutting)
>
>FWIW
>Hack
>
>
>
>>From: Michael Royer <mroyer@surferdude.com>
>>To: Multiple recipients of list <detomaso@realbig.com>
>>Subject: Re: pulleys
>>Date: Fri, 2 Mar 2001 16:51:24 -0500
>>
>>Kenny,
>>
>>Thank you for your careful reply.
>>
>>Here are some photos of the car with the alternator removed.
>>http://www.employees.org/~mroyer/cars/pulley.htm
>>
>>It is a one belt system.  The alternator is used to tension the one and
>>only multi-groove  belt.  The  belt pattern is a square.  It is a difficult
>>task to get enough tension to drive the alt, because less than 1/4 of the
>>pulley surface is covered.  It does not squeal, it just won't run the 3
>>radiator fans, AC fan, MSD and defroster fan while at 600 rpm.
>>
>>The  little  bolts, (four allen head things) were removed first with the
>>highest expectations for successful pulley removal.    I guess whoever
>>assembled it put the pulley on first.
>>
>>I considered just going to a smaller grooved pulley, but assumed this would
>>be even more likely to slip.  Considering all of the obstacles I'm finding,
>>trying a smaller pulley for the alternator is more attractive.
>>
>>I thank you and find the knowledge and encouragement with this club/list
>>fantastic.  Try to beat that with a Mustang club!
>>
>>(btw, My pre pantera muscle car is for sale)
>>http://cgi.ebay.com/ebaymotors/aw-cgi/eBayISAPI.dll?ViewItem&item=565188182
>>
>>Mike
>>
>>
>>
>>At 10:21 AM 3/2/2001 -0800, Kenny Hall wrote:
>> >First things first:
>> >
>> >If you are running a multiple groove pulley and belt (newer style), you
>> >only use 1 belt.  2 belts are used in the old single groove "V Belt"
>> >systems (by the way, they should always be a matched set).  Test your belt
>> >tension by either a tension tester (around $20 at the local NAPA) or the
>> >old "twist" method, multiple groove belts run tighter than V belts (I 
>> believe).
>> >
>> >Your charging problem is only related to the belt if it is slipping at
>> >idle (do you hear it squeal?).  If it is not slipping, test the charging
>> >system.  What size and type of alternator are you running, check the
>> >archives for discussion on alternators/rpms/charging, some don't start
>> >charging until a certain alternator rpm is reached.
>> >
>> >The "big" 15/16 bolt does not hold on the pulleys!  there should be 3 or 4
>> >(I've worked on too many different type to remember specifically) bolts
>> >(9/16 head) around the outside of the "big bolt" that holds the pulley to
>> >the dampener.
>> >
>> >Kenny
>> >
>> >(test the charging system first!)
>> >
>> > >>> Michael Royer <mroyer@surferdude.com> 03/02/01 10:03AM >>>
>> >I am working on getting a proper arrangement for my Pantera's
>> >alternator.  The way it is now, the ribbed AC belt moves the water pump, AC
>> >compressor and alternator.  When I installed the alternator, I had to
>> >change the pulley from V-belt to ribbed to match the extisting single belt
>> >system.  Presently at idle, I don't get enough amps.  On hot summer days
>> >idling with all the fans running, I get stranded unless I set the idle
>> >to  1400 rpm.
>> >
>> >Photos of other cars on the internet shows two belts.  A closer look at my
>> >car revealed that the alternator was sitting too far forward.  I can move
>> >it back easily.   But here is the problem.  I need to put a second pulley
>> >on the crank balancer.  Taking the existing pulley off is just too
>> >tough.  I'm not even at the shopping for parts stage yet.  How do I turn
>> >the 15/16th nut in the center of the pulley?  When I put enough leverage on
>> >it, the engine turns.  I put it in gear, the car rolls, even against the
>> >parking brake.  I need advice.
>> >
>> >Shopping for parts.  I can move the alternator easily (I think) and could
>> >find a pulley to add just behind the ribbed pulley.  Then I can make some
>> >guesses regarding how long the belt is and make a fit.  Sound right?
>> >
>> >How do I remove the existing pulley?  Should I  be scared that the engine
>> >will start as I'm turning the crank?
>> >
>> >Mike
>
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