My roomate and I finally finsihed up converting my slant to a serpentine belt





My heater core decided to dump a 1/2 gallon of antifreeze on me while test driving last night, so these pics were taken in haste. I will try to get some better ones when I have more time to work on it.

The conversion proved both simple and difficult; the hard parts being machining a spacer for the crank pulley (from junkyard) and machining the waterpump pulley. I was fortunate to have my roomate doing this for his senior design project, as I got quite a few hours of free machining out of the deal.

The power steering pump pulley is from a '96 intrepid (press fit), the alternator is from the same car. It puts out about 13.8 volts at idle, in gear, with the lights and heater on The automatic tensioner is from a mid-90's dodge caravan.

We fabricated a single bracket to hold the power steering pulley, alternator, and automatic tensioner. This was the first time either of us had welded, so we will see the strength of our welds as time passes

An added bonus to this conversion: I can take #1&2 spark plugs out without any universals, wobblies, or extensions....that is a huge servicability plus to me.

Next project on my list (after the heater core) is re-learning to tune a *(^%#$$# Holley!

-S/6

Man, you make me look lazy ... I haven't even got the 2-barrel in yet.

Seriously, that is cool!

Wow, can you take a few more pics, and write up this project? This kicks serious butt!

Great work.

Greg

I have several pics of the bracket fabrication and machined pulley & spacer from my roomates presentation (This conversion was done as his mechanical engineering senior design project), but I need to find a photo hosting site that is more reliable than photoisland and will allow me more storage space. Will post more pics as time allows.

We still have some minor alignment issues, when we braced the bracket we warped it a little bit, so the automatic tensioner and alternator are slightly out of plane. But, the belt is not showing any excessive wear or scrubbing as of yet, so we will be making some minor tweaks, again, as time allows.

Thanks for the compliments guys

-S/6

Nice job, it looks well done. But I have to ask, why? You took a simple two belt system and made it more complicated.

Hi K-man,

I am interested because I have had too many problems with V belts over the years. Slippage, glazing, shredding, and failure are all unpleasant experiences that I have had with V belts. In contrast, I have never had a serpentine belt ever fail on me, or slip exessively. It is a no brainer for me.

Greg

One reason was my power steering bracketry had become mis-aligned (slightly) over the years, and my truck LOVED throwing & destroying the p/s belt. It also liked to squeal quite a bit. I have some choice words if I ever meet the engineer that designed the slots for belt tensioning on the p/s pump as well In any case, as the p/s belt is the closest belt to the engine, it required removing the waterpump/alt belt to put a new one on.

Now, it only takes one belt, and with the automatic tensioner, all I need is a breaker bar and socket to remove/install a belt Added "bonus'" include:

Easy spark plug access
Newer style alt cured idle charging issues
Easier belt maintenance
Power steering pump has not made one squawk yet!

Then, there is the ultimate reason.....just to be different! I am unaware of anyone else that has a serpentine system on a slant, which is not to say it has not been done.

-S/6

Check out http://www.moparpages.com for photo hosting. That is where I upload all mine.

Jerry

_________________
There's a difference between ignorance and stupidity.
Ignorance is not knowing any better.
Stupidity is knowing, yet doing it anyway.

Here are some pics of the fabricated pieces for this conversion:

First, the crank pulley spacer/adapter:


The crank pulley came from a box of pulleys in at the junkyard, so I have no idea what it came off of. I looked for a part number stamped into the pulley, but it appears they were worn/rusted off for the most part, as I could only see a few numbers then they faded away. The larger aluminum spacer places the back (engine side) edge of the serpentine pulley in the same plane the back of the original V-belt pulleywas in. The smaller spacer replaces the crank bolt washer, and centers itself in the dampener. The larger spacer is machined with a recess that the washer fits in, centering the adapter & pulley.

Water pump pulley:


The hardest part of machining this pulley is the grooves. My roomate had to fabricate a tool to cut the "v's", which are a standardized shape (40* 'V') The tool he made got caught twice while machining. As a result, the pulley is ever so slightly out of plane. We will be taking it back up to the machine shop to true it up, we are pretty sure it shouldnt take more than .005 to .015" to true it back up. Quite honestly, if you didn't know to look for it, I dont think you could see the slight wobble in the pulley (Wobbles maybe 1/2 mm at the outer edge of the pulley)
The backside of the pulley (pictured) has a deep recess for placing the pulley in the correct plane, the front of the pulley has a shallow recess to center the fan.

Bracket:


We fabbed this bracket up from some scrap 1/4" mild steel. The power steering pump mounting point is exactly the same as the factory bracket, we just replaced the piece that bolts to the block with this behemoth. The p/s pump is what gave us the most alignment issues, as I believe the remaining factory bracketry was bent slightly. Acetylene torch, BFH, some creative bracing, and a lot of swearing took care of that

The automatic tensioner is mounted on a piece of steel tubing welded to the bracket to put it in the correct plane. Some of our final bracing welds seem to have warped the bracket a little, so we have some minor adjustments to do here as well. The tensioner makes approximately 95 lbs of initial belt tension (calculated & measured)

The alternator was the last to go on, and was really the easiest to make work. A few pieces of small diameter pipe were used as spacers over the loooong grade 8 bolt to position the alt in the correct plane. The top brace (not shown in this pic) is simply a piece of angle iron cut to length, and bolted to the head and alt. This bracket was our "backup plan" in case the automatic tensioner did not work out....it allows us to swing the alt to adjust belt tension. Fortunately, the automatic tensioner worked

Passenger side view:


This pic came out dark, but shows the crank pulley...somewhat. What it really shows is my newly gained access to plugs 1 & 2!

The following are not exact numbers, as I do not have access to them at the moment, but the belt wrap on each pulley is approximately as follows:

Crank: 95*
Waterpump: 110*
Tensioner:115*
Alternator: 180*
P/S Pump: 90*

As said above, I have not experienced any belt slip or sqeal as of yet. We were worried with the 95* crank wrap. According to our calcs, with everything drawing max load (including the fan), the belt should begin slipping at about 4200 rpm. I had it up to 5000 rpm last night and had no slippage I am unsure whether the fan was engaged though. I should also note that we estimated the power draw of each accessory, as I could not find much documentation for actual numbers.

25.6 miles on my slant now, with 23.2 of those on the serpentine system. Hope to have over 2000 miles on it by the end of May, so I can see what this heavy beast will do at the track. She really comes alive at 3000 rpm now, and pulls clear through 5000 rpm (maybe higher, that's where I backed off). She used to fall flat on her face at 43-4400.....that head work and compression bump must have helped things upstairs quite a bit

Whew! Sorry for the book. I have more pics and can take more if needed.

-S/6

That is a great looking setup Aaron.

I can't tell from the pics, but it looks like you even got the water pump turning the right direction.

Our GM systems at work require a reverse rotation water pump.

_________________
Official Cookie and Mater Tormentor.

'Ye of little faith....the w/p definitely spins the correct direction

I apologize for the quality of the pics. I will try to get some better ones. If a reverse-rotation pump were available, machining or adapting a w/p pulley would have been much easier. Cutting six 40* grooves in aluminum billet, and getting them all parallel to each other was a royal PITA, as we had to make a tool to cut the grooves---three times. The tool removed so much metal it got caught and snapped twice, and we were keeping the lathe RPM's very low, and trying to remove material as slowly as possible. We went through a LOT of machining oil.

If I were to do it again, I think I would spend more time scouring the boneyards for a pulley to adapt to the w/p. It is easier to machine a spacer/adapter than a pulley.

Thanks for the compliment Dennis.

-S/6

Very innovative, well thought out ,,,,and very cool. I hope your roomate got the marks he deserves. Im surprised you got that pulley machined. It shows what can be done when you don t know the task is impossible.

_________________
Yeah....Im the one who destroyed this rare, vintage automobile.....

Saul's (my roomate) instructor seemed impressed, I think it helped that he was driving an early 70's A-body with a slant

I am sure he will make a good grade, compared to many other student's projects Saul's was much more involved both in theory (belt friction/tension/scuff, drive ratios, belt angles, etc) and in application (fabrication and machining). Plus, this was the only project that had a functional prototype---I drove it up to the University for his presentation, and over half of the Mechanical Engineering Dept. professors came down to take a look.

Looking over my previous posts, I noticed I neglected to thank Saul for all of his time spent on this project. I could not have done it without his machine shop access & experience. Thanks Saul!

Thanks Sandy, nothing is impossible on a slant, except sealing the oil pan to timing cover from leaking oil

-S/6

Hmmm ... I don't suppose you have any drawings, sketches, dimensions you'd care to post, do you?

I have AutoCAD (2002) drawings of the w/p pulley and adapter for the crank pulley, both with dimentions. I do not have any CAD drawings of the bracket though. I have our initial measurements for the bracket, but we ended up putting a couple "calibrated bends" in the bracket to line my bent power steering bracketry up, so they are only close at best. Will try to get the CAD drawings and some measurements posted for you.

-S/6

Here are the CAD drawings of the w/p pulley, crank spacer, and crank washer. Still looking for bracket measurements.....

W/P Pulley:
W/P Pulley

Crank Pulley Adapter & washer/centering adapter (Remember I do not have a P/N for the crank pulley I used )
Washer
Adapter

All dimensions in the above CAD drawings are in decimal inches.

-S/6