temp2

I got a S/C coupler from ebay a few days ago, it looked just like what zzp sells. Well i received it in the mail today and it looks a bit different. Its still round with one big hole in the center and 6 little holes around it, but its a darker green and there are no "ridges" around 3 holes on each side, meaning the coupler is completely flat on both sides. I could care less about the color because it was half price of zzps, but am i going to run into problems without those spacing "ridges"? Thanks in advance.

Hard to tell.

I got my coupler from http://www.darossi.com, if that's any help. You could click on that site and look at that coupler. I got the kit including bearings and SC oil. The coupler is machined from a green oil-impregnated polymer.

DaRossi claims its flat coupler is sturdier than OE as well as sturdier than the replacements that have the standoffs molded or machined in.

The "splash" page of the DaRossi site shows the couplers *with* the standoffs.

What to do: use your own judgement. That said -- I've been running a DaRossi coupler for more than a year with *no* issues.

Albertj

That actually helps a ton! The ebay username of the seller just happens to be darossi, and referred to the zzp/stock design as "inferior". I will give this coupler a try, thanks albertj!

Lol, inferior? I don't know about all of that. To me it looks like he got the idea to use the oil-impregnated polymer from ZZP (it's the same stuff), then decided to skip the stand-offs to save machining time.

What you're getting is a ZZP coupler at a really good price. Hopefully, Darossi stands by their product as well as ZZP does.

AA wrote:

Lol, inferior? I don't know about all of that. To me it looks like he got the idea to use the oil-impregnated polymer from ZZP (it's the same stuff), then decided to skip the stand-offs to save machining time.

What you're getting is a ZZP coupler at a really good price. Hopefully, Darossi stands by their product as well as ZZP does.

Thats what i was thinking, even looks like he bought a bunch of zzp couplers for his ebay picture. My only concern was if the lack of those ridges, or "stand-offs" as you called them, will effect anything.

Haha, you're right, those are ZZP couplers, or some good imitations! Hilarious. He probably tried to make them that way at first, and found out there was a faster way. Profit is all about production speed in this business.

All the stand-offs do imo is keep a little clearance between the gears and the coupler, which probably allows for better oiling to the pins from both sides. If you really think about it, his design might be the inferior one. Or, it might not matter at all. I think the material itself is what makes the product superior to OEM. I have over 100k miles on my ZZP coupler. It's holding up very well, but if it decided to give out tomorrow, that's $30 well invested in my book.

FWIW, there's another seller on eBay with 100% positive feedback on over 2100 auctions selling rebuilt snouts and blowers:

http://motors.shop.ebay.com/itsells4you/m.html?_trksid=p4340.l2562

From the auction's description:

"Our coupler is proven in thousands of rebuilds and is the best available. This coupler is made from green oil impregnated polymers. The same coupler proven and used by top rebuilders American Supercharger and top 3800 performance shops. ANY other material can break down like your stock coupler. This coupler has the correct oil stand offs just like oem. Most couplers being sold on ebay do not have the oil standoffs and may cause premature failure of your supercharger."

So, it seems anyone who can machine a coupler out of the magic green plastic becomes an "expert" on the topic.

So those stand-offs ARE for oiling? He claims that his coupler is thicker without the stand-offs and makes it stronger. Nevertheless, i already have it so i might as well give it a shot right?

I wouldn't use it. jmho

97 park ave wrote:

So those stand-offs ARE for oiling? He claims that his coupler is thicker without the stand-offs and makes it stronger. Nevertheless, i already have it so i might as well give it a shot right?

not really sure... I suspect the standoffs are on the OE couplers 'cause IIRC they are injection molded and would be weaker at the pins without them. I have no idea if the replacements are better or not with standoffs. I kinda wonder how the oil gets to the pins at all.

It may amuse you to see that the coupler offered by Dorman (pic via RockAuto.Com) also has no standoffs:



You want something to think about ? try this: at the combination of 10+ years old and 150,000+ miles our cars are past their engineered "lifetime." No?

albertj wrote:

97 park ave wrote:

So those stand-offs ARE for oiling? He claims that his coupler is thicker without the stand-offs and makes it stronger. Nevertheless, i already have it so i might as well give it a shot right?

not really sure... I suspect the standoffs are on the OE couplers 'cause IIRC they are injection molded and would be weaker at the pins without them. I have no idea if the replacements are better or not with standoffs. I kinda wonder how the oil gets to the pins at all.

It may amuse you to see that the coupler offered by Dorman (pic via RockAuto.Com) also has no standoffs:



You want something to think about ? try this: at the combination of 10+ years old and 150,000+ miles our cars are past their engineered "lifetime." No?

Well, if dorman is doing it i would assume it cant be harming it. Dorman usually seems to have decent parts.

I have an even bigger question than HOW the oil gets to the pins, WHY do the pins need to be oiled? If you stop and think about it, the pins get inserted into the coupler and there they sit. They dont spin inside the coupler they apply lateral pressure to the holes. Its kind of confusing, one way i look at it the stand-offs make sense, the other way no stand-offs make sense too. I think im just going to use it as of now, if it looks wrong when i install it then i might not use it.

So the OEM ones have those standoffs? Interesting topic... I wouldn't be worried about it if Dorman doesn't include that in their design. Granted it might not be optimal but I doubt it would cause an issue. But hell, I'm not from Eaton so wtf do I know? :/

DEMonte1997 wrote:

So the OEM ones have those standoffs? Interesting topic... I wouldn't be worried about it if Dorman doesn't include that in their design. Granted it might not be optimal but I doubt it would cause an issue. But hell, I'm not from Eaton so wtf do I know? :/

Eaton/intense/zzp all show the stand-offs, while dorman/ebay do not. Its hard to say, cause like i already said i can see it both ways. Ill probably go out and pull the snout off a spare to see how the ebay one looks in a bit.

I wouldn't worry about having/not having the standoffs. The previous quotes refer to oil breaking down the material of the coupler. Not to oiling the pegs,(which would be stupid, its a shaft to shaft joining piece) Oiling does not matter, its just what it sounds like. A coupler. It couples the snout drive to the rotor pack. You don't want those pegs lubed up, just a tight fit. Its there so if something binds your rotors, it won't screw your engine. (though If you think about it, the metal pegs would just hit each other if the coupler shattered). Its interesting to note too that the Ford ones, and also the one in my Jaguar m112, are "sprung" , in that they have a spring in them to soften the initial force of the boost, and supposedly to eliminate the "worn coupler" clatter we get.(though the ford guys swap it out for "our" coupler anyway since it seems to cause the opposite.) As long as the material is good, just pop it in and go with it. The only advantage I see to the stand off ones is it would be easier to remove in dis-assembly, if it was frigging tight and you needed to get something behind it to pry.(which should really never happen)

(also of note, I once got one from ZZP with no stand offs. Way back in the day.)

Karma wrote:

I wouldn't worry about having/not having the standoffs. The previous quotes refer to oil breaking down the material of the coupler. Not to oiling the pegs,(which would be stupid, its a shaft to shaft joining piece) Oiling does not matter, its just what it sounds like. A coupler. It couples the snout drive to the rotor pack. You don't want those pegs lubed up, just a tight fit. Its there so if something binds your rotors, it won't screw your engine. (though If you think about it, the metal pegs would just hit each other if the coupler shattered). Its interesting to note too that the Ford ones, and also the one in my Jaguar m112, are "sprung" , in that they have a spring in them to soften the initial force of the boost, and supposedly to eliminate the "worn coupler" clatter we get.(though the ford guys swap it out for "our" coupler anyway since it seems to cause the opposite.) As long as the material is good, just pop it in and go with it. The only advantage I see to the stand off ones is it would be easier to remove in dis-assembly, if it was frigging tight and you needed to get something behind it to pry.(which should really never happen)

(also of note, I once got one from ZZP with no stand offs. Way back in the day.)

Exactly what i thought, well, at least one of the ways i was thinking lol. Coupler goes on today.
And anyone looking for a cheap coupler type in "m90 coupler" on ebay. Thanks for the input everyone!

OK, Work with me here as I am new. I have a 1995 S/C Riviera that is stock with 99,000. Has developed a rattle at idle that after a lot of reading and research is the coupler which I plan to do myself. Plan on changing the oil and all that fun stuff when i pull off the nose to get the coupler. I am the second owner and the car runs flawlessly for the most part and is in excellent overall condition. had it for 4 years I plan on doing upgrades as I go along and can afford to do so. Had the choice of a Grand Prix GTP or the Riviera and loved the Riviera by far. Any advice on doing this job would be appreciated as I have had two spinal fusions and eight shoulder surgeries. I have looked over a lot of threads here and this is an incredible site for a great underrated AMERICAN car.

So what in your all's fine opinion is the best, most durable coupler to get? I also plan on replacing the belt and some other stuff. waiting ion a my tax refund before I can do anything.

I am in Redmond, Oregon.

Hey there fellow Oregonian.
Rockauto has the coupler Dorman brand part # 917022 for $10. I'm sure there are other places but my guess is they are all the same part. Just remember to grab the super charger oil from the deal before you start.
The write-up on this site is probably the best out there so follow it step by step and you should be good to go.
While you're there on Rock Auto, check out the pulleys for your belt system. IMO it's time that kills these cars, not mileage so just because you have fairly low miles does not mean the parts should last that much longer.
Good luck and take some pics of your ride. wish you were closer and I'd come help.

If your certain the sc coupler is the culprit it is an easy fix. That being said I would also recomend that you spin and listen to each pulley once you have free'd them from the tension of the belts. If you see or hear anything you don't like then you'll have a heads up to repair it before she ever leaves you stranded.

I changed my failing stock coupler to a ZZP version at around 150k miles. Still good at close to 250k miles, I wouldn't use anything else.

Has anybody bought from this person http://www.ebay.com/itm/Eaton-supercharger-coupler-M90-Thunderbird-Etc-New-BIN-/130728673854?pt=Motors_Car_Truck_Parts_Accessories&hash=item1e7009423e&vxp=mtr?

98riv wrote:

Has anybody bought from this person http://www.ebay.com/itm/Eaton-supercharger-coupler-M90-Thunderbird-Etc-New-BIN-/130728673854?pt=Motors_Car_Truck_Parts_Accessories&hash=item1e7009423e&vxp=mtr?

Yes I have a DaRossi coupler, works fine, I bought the kit that contains the needle and roller bearings as well, overhauled the supercharger as long as I was in there so to speak. Not a terrible job other than the SC oil really, really, really stinks.

Albertj

There is some discussion of Darossi couplers on a previous page of this thread. Not sure how much was concluded.

My idea is to mechine a coupler out of aluminum using same dimension as the plastic ones. Has anyone tried this? Dose anyone have any thoughts or concerns with this idea?

I didn't design the Eaton blower, but I have to believe the coupler is there for a reason. They didn't have to include it - could have easily just driven the rotors directly by the shaft, but they didn't. I believe it's a stopgap for the dynamically changing loads the blower operates at, and abrupt changes in RPM. The coupler may help insulate the rotors from the belt driven shaft, giving a little elasticity to help isolate from shock, vibration, and extreme load.

By coupling the shaft and the rotor drive with something as rigid as aluminum, it could make more noise, or it may decrease the life of the blower. Not for sure, it's just a thought. Also, if anything ever binds up or jams, the coupler won't fail, so your belt will rub on the frozen pulley until it slips off, melts, or otherwise fails.

ZZP makes a coupler from a tough plastic that has lasted over 100k miles on my car. It's $35, and still working like new. If I ever need to replace it, another $35 + 1 hour to swap, and I'm fine with that!

There are a few reasons for the phenolic coupler.
-They act as a dampener between the 3 pegs and your rotors. Think of it as a "dead blow" hammer. It still transfers the force, but without the component damaging shock. Many Ford and Jag units actually come with a spring loaded coupler that can turn a 1/4" against the spring before being a solid connection. This is to get the rotors moving up to speed a bit and prevent belt slip. This can also help prevent the belt from jumping when going on and off throttle.
-It is just as strong as aluminum. phenolics in many cases are stronger than 4140 steel. Combine that to being just as light as aluminum, its huge pressure and temperature withstanding ability and it makes sense.
-And the main reason: A metal coupler would not last nearly as long, would wear out very quickly, and would not fit as tight. Trying to get a metal to metal fit is extremely difficult and the distance between the parts would *always* be further apart than with a plastic. The plastic can deform very slightly to provide a tighter fit; this means it can be machined to end up at a much tighter tolerance.. Additionally, the phenolic coupler is oil impregnated. As it wears it absorbs more oil and expands slightly closing up the holes again. That is how it lasts longer with a tighter fit than a metal coupler.

So in a nutshell, Eaton knew what they were doing by using a superplastic.

OK thank you both for your input. I did over look somethings and have decided to not make the attempt.