aluminum underdrive pulleys are a MAINTAINENCE item
 

so you have a set of those cool aluminum underdrive pulleys and think they are pretty neat. they are.

for a couple of years.

pop the hood. grab the water pump pulley and try to turn it. my guess is the odds are 50/50 you can.

if your belt is adjusted fairly tight and you can turn your water pump pulley guess what happens to your cooling above 5000 rpm?

the problem is the back side of the belt is the only pulley contact. there are a bunch of degree lines machined into the surface of the pulley to promote grip. since they are only a thou deep and the material is aluminum it is bye bye traction in a couple of years.

so what are our options?

it doesn't make sense to drop $200+ on a complete new set of pulleys. and i don't think anyone sells just the water pump pulley... which is the ONLY pulley needed.

i took my pulley into the local machine shop and asked them for a quote. they will do a diamond (that's diagonals going both directions) for $159 which includes setup and programming. they can do a bunch for $59 thereafter...

anybody have any better ideas?

check your tires. check your pulley.

howard coleman

I was just going to say you can buy both the alt and W/P for $40 shipped on Ebay. Then you can sell off the spare alt pulley or just keep it as a back up.

the FD waterpump has a press on pulley? why not cut a key way into the pump and broach the pulley itself

if the pulley already was knurled and it wore down, doing it again probably wont work for very long as for the raised portion of the knurl wont be nearly as tall as the original

I know if you go to a shop with a manual lathe, they can dut a basic knurl on for under 20 bucks...

hes not talking about the pulley slipping on the pump but the belt slipping on the pulley

any1 no the best place to get the pulley and belt and blocking plats to remove the airpump

Or you can buy an airpump idler pulley and have your belt go most of the way around your water pump pulley.

Or go EWP ;) just playin'

[/quote]This is why I dont understand poeple paying a couple hundred bucks for "the real quality brand name item" when you can get the same thing for 40 bucks on ebay, and if it wears out or tears up then big deal, you pick up another set a couple years down the road.

Why not just put the pulley in a vise and use a center punch to make a bunch of dimples in it for grip? IT might not look like it did when it was new, but it should function well and be free.[/quote]




I got mine for the preety...LOL..

http://img.photobucket.com/albums/v2...S/DSC_0115.jpg

+1

I don't know about the price, but a real shop with a [manual] lathe and real machinist can cut a knurl onto the pully. Aluminum is relatively soft and it's very easy to put a deep knurl on it. Setup is the time consuming part of this gig, cutting the knurl will only take a couple of minutes.

This is why you use the pineapple idler pulley kit (or similar idler pulley) instead of that vastly inferior Greddy kit. That Greddy kit scared me with how sketchy it was... I know a lot of people use them with success, but it just didn't seem like the proper solution to me.

Ah, ok i understand

Howard,

Do you feel this is a problem when using the airpump also? Having a good surface area of belt to pulley contact is a key element here also.

http://img.photobucket.com/albums/v4...0813081847.jpg

If you still have the airpump, then you wont have this issue.

REALLY good post, Howard! I never considered that, and it makes perfect sense.

Seems like Pineapple is going to start getting a bunch of orders for their idler pulley!

Dale

You just have to convince them to make it again! I am not sure if they started again or not.

Garfinkle has one in fab...stay tuned.

if you know his oil pan brace or engine torque brace...you know the quality this thing will be.

howard and pineapple are probobly in cahoots with each other. haha

Actually, it's the angle of the contact surface and its coefficient of friction (CF) that are important. It's called the "capstan effect" from sailors using multiple wraps of rope on a post so that a few # of tension can hold an ocean liner from moving. The force to slip is exponential with CF and wrap angle. If the angle times CF is small, not much torque can be transmitted. Page 4 of the linked explanation below shows how this works.

http://pergatory.mit.edu/2.007archiv...Components.pdf

So increasing either the wrap angle or the CF will improve the situation.

So I have had the greddy pully kit on my car for roughly 3000 miles and one day a little after I got on it my car all of a sudden started getting warmer than it ever had before.....went out and checked and yup I can turn my water pump pulley with my hand.

So lets see I spent 140 on greddy pullies to eliminate and air pump and have higher water temps and now have to fork up the 170 for the idler pulley...this is crap!

BTW thanks howard for another informative thread.

thanks Banzai/Chris.... i tripped over to ebay and found a couple of vendors that offer a 2 pulley (alt/water pump) deal for 41 shipped.

i also took one of my spare wiped out water pump pulleys, my set of punches and in short order had a whole lot of "H"s punched into the mating surface. for anyone not wanting to spend the $41 that would be a simple option.

plus it relieves stress if you have any.

hc

Remember, do NOT over tighten the belt to prevent the water pump pulley from slipping. If you tighten the belt too much, you will pull up on the E-shaft and cause premature wear on your bearings!!!!!!

Chadwick do you have an idea on the price of your idler pulley?

what about the guys with LARGE singles? we have no room for an idle pully.....

pineapple used to make one as stated above. perfect even for guys running large single, It is the size of a half dollar in diameter. They really need to make them again.

they really need to, mine spins really easy...... so it sucks, i have unorthodox pully set and am only Running alt and waterpump... so yeah i need to do something, i think i am going to cut ribs into my waterpump pully and see if that helps at all....

Chadwick-Dan----- please keep us informed on the production and availability as soon as possible. if knowledge was a given on this issue with the slippage these should sell like hot cakes. what manufacture are you using for the bearing???

subscribed..

Is there any chance that you will be offerering different colors? for example I have the greddy kit and it would be nice if that pulley was blue as well.

I will have to keep my eye open for these to come into group buy :)

-Chance

sure enough mine slips too. howard have you tried the modified pully with the H's etched into it? did it improve the grip?

too bad there isnt a belt replacement that has some kind of ribs on the outside, course that might eat through the aluminum even quicker. I like how much simpler the engine bay is without the extra belt routing, there must be a good solution besides adding more or new parts.

This is exactly the reason why the pulley they were selling cost so much. If you use a larger pulley it hurts turbo clearence but also puts much less strain in the bearing inside the pulley. They were able to go so small on their pulley because they were using a bearing that was good to an extreme RPM. This greatly increased their cost. The original price was close to $300 I think and I heard they still lost money on the deal. The little CNC bracket and bolt cost was trivial in comparison.

Personally I didn't need the huge clearence, so this pulley by Chadwick would have most likely worked for me.

The solution you are looking for is an electric water pump.

Maintaining the OE water pump requires you to use at least close to the stock amount of belt wrap. The only way to do this properly with the air pump gone is to install an idler pulley. There is no other way. You might be able to make some more elegant belt routing with a different pulley location (like the hot rodders do) but you have to have the wrap with the OE water pump, and this is the best way to get it. The idler pulley is in my opinion a very elegant and slick solution. Much better than the Greddy pulley kit which is just a very poor solution to the problem...again IMO. But then again, they got me to buy their kit before I realized that I needed the Pineapple Pulley to really be safe and eliminate belt slip.

FWIW. I posted my Pineapple idler pulley for sale and sold it in less than 15 minutes for, I think, $165 shipped. I got PMs more than 3 months latter from people wanting to buy it from me. I think there is a market there if someone can produce a good solution.

What about an electric water pump ?

Another option instead of the standard aluminum underdrive pulleys are glimers. I know they make gilmer pulleys for 1st gens and 2nd gens, but never seen one for the 3rd gen.

http://www.tweakit.net/shop/product_...roducts_id=102

I know this could be accomplished by using the front housing/water pump from a second gen.

Yeah I really want a set like that.
But if you use the front case off a 2nd gen, then wont you need a custom oil pan?

i just tried mine and sure enough it spins with little effort, great design Greddy!

If the grip on the w/p pulley was rubber I dont think we would have this problem

so my noob question of the month:

Can I just turn the belt inside out? So the ribbed side hits the waterpump and since the alt and crank pulley have more surface grip will be ok???

^^^NO the 5-v-bans are there for a reason. the only current solution with out highly modifying would be retain your air pump or the pulley.

:wallbash: :wallbash: :wallbash: :wallbash: :wallbash: :wallbash: :wallbash: :wallbash: :wallbash: :dammit:

Wow, for once I can say I'm glad I still have my air pump connected?
I was thinking about removing it too but with California smog Laws and My laziness, I have left it on.

^^^^ same here lol

The other thing about the multi-groove belt is that, like a standard V-belt, the "V's" wedge themselves into the pulley grooves, providing more surface-contact force and area and result in more torque capability. A flat belt (or a V-belt running on a flat surface) does not have that advantage.

Dave

Another idea that came to mind would be to fab an alternator adjustment bracket that allows it to be pulled higher, allowing the belt to hug the waterpump pulley some more.

I guess the belt contact wouldn't be a much as we would like, but it can be just enough with the larger diameter aftermarket waterpump pulley.

Any thoughts?

anyone think of adding a grooved pulley to the water pump, and using two belts? one going around the alternator and main pulley, and the other one flipped inside out to hug the water pump one?? if that makes sense

just a thought

Yeah that makes sense. I thought of that too. I don't know if the two belts would ride on eachother correctly. Maybe if the other pulleys were deeper or the belts were glued together. Then there is still the issue of contact area. Although with two belts it would put more pressure on the pulley even if it wasn't a grooved pulley it might work better. I thought of using some kind of rubber stuff on the outside of the belt to make it stickier but that would prob wear off in short time

keep in mind that the slippage occurs at the higher RPM range and once the heat come in to factor the only real solution to insure the proper water pump rotation is maintain your stock air pump or install a idle pulley. :( just wait for the group buy or start calling paineapple racing and put pressure on them for a re-run

The pinapple idler kit will need the stock alt and water pump pulleys correct?
Does anyone know if it will also use the stock belt size also?

^^^does not!!!! you can us any aftermarket pulley it is designed to maintain the original belt travel path. and the size of the belt needs to be smaller after installing the kit. same OEM path but shorter. the original pineaplle pulley is the size of a U.S. half dollar.:)

Well i had a problem sizing belts, so i ended up with a bunch, pretty much you can find them in 28.5inch, 29inch, 29.5inch, and 30inch. They fit into each other quite nicely, so i don't see there being a problem of contact.

would changing the rotation of the water pump work? My friend put the belt on the wrong side of the pulley one time, and ran it for maybe a week until i told him it was backwards.