I've been reading and learning on the forum about the debate between replacing with a spring Isolator / coupler (which SuperCharger Online sells) and the solid isolator (which e.g. Powerhouse UK or ZZP Performance sells). These threads, amongst many, were helpful: - thank you.
https://www.jaguarforums.com/forum/f...er-faq-268068/
https://www.jaguarforums.com/forum/x...-249262/page3/
https://www.jaguarforums.com/forum/f...rattle-194718/

This came about as I have the supercharger snout rattle. Is there any consensus yet on which coupler / isolator is better for the X351? (I have a V6) And if any particular rebuild kit is best given I have the play in the snout, and hence the rattle... (35k miles) Also what about the worn shaft? If it is worn, do you replace or leave it alone? - if replace, best source? Many thanks...

Post # 31 in the 2nd thread caught my eye, but do not quite understand it all: -

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Quote:
Originally Posted by clubairth1
I wonder if the spring loaded coupler acts as fuse or weakest link in the system? As an Engineer I have worked on systems that were setup so the least costly item failed first and protected more complicated and costly components from damage.
.
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Vincent V - replied:-

"I now believe that this is what the manufacturer intended.

The cheapest and easiest to maintain components are subject to wear and tear. Now I have opened the supercharger and I can see it. (3.0 SC) The spring coupler is designed in such a way that all the shock load that it could not damp is transferred to the needle bearing, which is easy to replace. This is achieved by springs that apply a force at an angle to the axis of rotation. The main load is taken by the snout. Thus, the rotor bearings and gears are maximally protected.

At full throttle, the clutch is fully engaged on all three pins and the force is strictly on the axis of rotation. At this point, the spring coupler is equal to the solid coupler. However, torsional vibrations at high revs are much less.

The rest of the time the coupling dampens torsional vibrations. And at partial throttle or idling, the car works most often.

This may be why the solid coupler is quite useful in racing, where full throttle, and supercharger life do not matter so much.

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It seems getting this repair wrong could end up being very expensive down the road, so advice is much appreciated. It also seems this and the water pump / coolant pipes upgrade may be the two most important things we can do for long term reliability on an X351, and that can also be tackled somewhat simultaneously to help save labor (although I understand some say the SC does not need to come out when using a rebuild kit...)

Thanks...

PS - I'm not look for any increase in performance - just the best choice for long term reliability

 

I replaced the OEM coupler with a ZZP coupler at around 110K miles on our 3.0L RRS (same engine as yours). The original coupler really wasn't that bad and the rattle was pretty slight. With the ZZP coupler, the noise from the engine bay was definitely less and everything seemed great. Now, around 8K miles later, the supercharger is making a bit of a growling noise, and when I removed the belt, the pulley feels a little gritty as I turn it. It was dead smooth before. And there seems to be a little bit of play that was not there.

I have not diagnosed it any further yet, but I am sure I will be forced to soon as whatever is making that noise will most likely get worse. But whether it's the snout bearings are shot, or the supercharger bearings are shot, it won't be easy to know if it was just time/mileage that caused the issue, or the ZZP coupler. It is a lot of miles. I did change the supercharger oil at the time with the GM oil. Could that also be the issue? Or the fact that the oil hadn't been changed for the first 100K miles, if it the supercharger's bearings. Who knows! But if I had to do it again, I would probably go with the OEM coupler and just make it a routing maintenance item in my mind instead of trying to find a lifetime solution.

 

Thanks, that is helpful. It is also good that you are staying on top of it, especially given you have good mileage under your belt with it, so to speak....

Good luck as always !!

 

I bought the front snout kit from Jaguar and stuck with the OE coupler that was included. I also changed the supercharger oil at the same time. I’m now 30,000 miles in and it’s still working well. Overall the car has 115k miles.

 

If the OEM couplers are lasting ~100k miles, probably best to stick with them.

 

Thanks Nedoerr, that is helpful.

The Jaguar part I saw seemed to be only for the 5.0 litre, but I presume they are the same, for the 5.0 and the 3.0...
https://parts.harperjaguar.com/oem-p...r-kit-c2d58056

In any event I found this one for the 3.0 litre but it may be poor or good aftermarket? One question might also be, like the water pump, is that the most recent part number?
https://www.wholesalepartsexpress.co...3104-c2d40425/

The main thing I'd like to find out is if there is a reliable version besides having to buy from Jaguar to save the $500 +? I managed to get a good Denso Alternator for $259 (with LIfetime warranty (?!) from FCP Euro), and that from Jaguar was $939 I think
https://parts.harperjaguar.com/v-201...al--alternator

This seems well recommended, albeit with a solid coupler: - for about $350
https://powerhouse.uk/supercharger-p...-rebuild-kits/

 

No. The 5.0 and 3.0 use different couplers.

 

I remember now, and stand corrected, 49mm vs 46 mm, correct?

 

Correct. Plus the depth is different as well. 25mm for the 3.0 vs 19mm for the 5.0

 

You sure do know a lot - thanks. BTW how is Cape Town, I used to live there to train at the Sports Science Institute! Tim Noakes's amazing place... What an amazing town.

So, back to the topic - what rebuild kit would you recommend, given, f possible, I want to avoid spending the $900 on the Jaguar OE part...

 

By chance I have a 5.0 and a 3.0 coupler sitting on my desk next to my computer so I whipped out the tape measure and also took the above photo. I did not actually have the measurements in my memory bank. The only thing I knew for sure was they are both round with 3 holes.

Cape Town is amazing for sure. I am not familiar with Tim Noakes,s institute but know the area.

I have used a few different suppliers over the years (one shown below) and always successfully used the solid couplers but recently I had 2 cases where there new coupler improved but did not completely sort out the SC noise. I dont know why but I am wondering if OE type couplers would have done the job better. One of these days I may experiment with the noisy vehicles and fit the OE couplers to see what happens.
https://powerhouse.uk/supercharger-parts-rebuild-kits/

 

"easy to replace"?

Is there somewhere a guide for this?...to replace the bearings?

I'd like to get this done at the same time, whether I need it or not.

 

I don't know if someone's made a guide, but you take the supercharger off, disassemble and use a pulling tool to remove the bearing and replace the bearing.
The only hard/time consuming part is removing the supercharger.

If you search needle bearing removal on an eaton supercharger, you'll see a few examples on youtube of folks doing it.

 

Is this the process?

 

I actually just searched on youtube, here is the 5.0 version Eaton TVS1900 IIRC is what our cars have. This is the exact process: