Write-Up: Supercharger Coupler Replacement (Series II)

No gastket, just a thin bead of RTV or whatever came with your coupler.

This site is awesome! Riv Owners RULE!

Ok, replaced snout with sealant, put it back together and still leaking, what do I use to clean off the sealant and reapply? Im thinking I either didmt tighten it correctly or I puttoo much sealso it didnt close all the way? Also I failed to mention that when I pulled the snout off, partof the upper intake gasket came off with it...isnt that the part that some of you cut off?

When you say thin, how thin is a thin layer

By thin I mean about the diameter it flows out of the squeeze tube. As long as it you get all the way around without any gaps, it shouldnt leak? When we did mine, the gasket maker was only a few mm. Its weird that you're still getting a leak after removing it and putting new gasket maker in. Did you let the gasket dry good before filling with oil? And does the surface you apply the RTV stuff to look corroded where it would not sit flush?

There must be some damage or debris on the mating surfaces. I used NO sealant when I assembled mine, and it doesn't leak a drop.

I will take it apart again, recommendations for cleaning debris, sealent off? Im willihg to bet I didnt let it dry. Now, let it dry before I put it back together, or put it together and then let it sit?

I always use a razor blade to clean off all of the debris. And I meant put it together and let it dry, before adding the oil again! Like AA said though, if the surface is clean and nit damaged or worn in any way, it should be flush enough that the gasket is only insurance.

Alright cool, so remove it, clean off with razor, reseal, let dry first before adding oil, how long did you let it sit?

Most people say it takes a few hours to cure and around 24hrs to dry. If you wait 2-3 hours that should be fine but if you not dependent on the car to go somewhere right away might as well let it set a bit longer!

Alright thats what I will do then. Thanks

Son of a b.... took the snout off again for the second time, resealed it, its still leaking, what sequence was use dto tighten the bolts down? ! Im about to give up

i think i have my old snout around here somewhere. needs cleaned and the old drain plug taken out (stripped head) and of course a new one put back ( 8 bucks gm dealer). if ya want it its yours just pay shippin. let me know and ill look for it

I feel like you either messed the snout up, or you're not using enough sealant. Maybe post some pictures of the bare metal and how much sealant you're using? Is the belt lining up right and not squealing?

Belt is lined up correctly, no squealing . seems to be coming out of the bottom. How did you guys tightened the bolts? Top to bottome, left to right etc. As far as the sealant goes. When I put the bead around the snout, am I supposed to spread it out into a thin layer or no?

I know this is a little extra work, but by removing the entire supercharger you can have better visibility as to where the leak is coming from. The blower should hold SC oil off the car. It will also permit you to replace the SC gasket with a fresh one.

highwaywarrior wrote:

Belt is lined up correctly, no squealing . seems to be coming out of the bottom. How did you guys tightened the bolts? Top to bottome, left to right etc. As far as the sealant goes. When I put the bead around the snout, am I supposed to spread it out into a thin layer or no?

tightening order doesn't really matter. RTV should be very very thin, but some guys don't even use it. The surfaces are machined and should seal just by tightening. The surfaces aren't gouged are they? Or perhaps its your snout seal thats leaking?

Hm, i dont mind taking her apart again. I didnt look damaged or anything when i cleaned it off again, the second time. Also when i took it off. The red sealant wasnt even on the machined surface it spread to the outer parts. So here what i will do, take the sc off and see where its leaking. Take the snout off and use a different sealant RTV high temp?

Snout seal looks good lol

I've developed a choo-choo train sound which seems to be coming from the SC snout -



What do you think?

Incidentally, the chirruping you could hear in my new alternator @1:00 here appears to have gone away -

For future ref Abaddon says the SC coupling makes a rod knock sound at idle (only at idle), so that rules one possibility out.

I ran the engine with the SC belt off, the choo choo sound is definitely coming from the SC.  I checked the SC oil level, that's fine.  I can't feel any play in the coupler, but I can hear some little impact sound back at the base of the snout when I switch directions rocking the pulley back and forth.  If there is an play it has to be tiny, like a 1/32 or 1/64.  Turning the pulley doesn't feel buttery smooth, but there's nothing that jumps out and says "this is a bad bearing."  I guess it could be, but from what I've been reading so far the bearing is not likely to fail.  I'll keep an eye on this and see what happens, unless someone spots a/the problem.

That doesn't sound right to me. When you spin it, it should be relatively noise free. Yours is making a "zipper" type sound. Unless it's the video making some weird feedback.

Correct on the coupler noise. The coupler has 6 holes, with 3 on each side. They're offset of each other. The snout gear has 3 pins, and the rotor gear has 3 pins. The coupler is what mates the whole unit together. Over time, the (not metal) coupler wears out, and the holes oblong.
The 3800 naturally misfires at idle. Those misfires, cause a momentary "stoppage" of the S/C, which causes the pins to slam against the coupler. The sound gets worse as the engine warms up. If you ever hear a knock from the upper engine area, put a stethoscope (or screwdriver) on the S/C and to your ear......

Abaddon wrote:

That doesn't sound right to me. When you spin it, it should be relatively noise free. Yours is making a "zipper" type sound. Unless it's the video making some weird feedback.

Correct on the coupler noise. The coupler has 6 holes, with 3 on each side. They're offset of each other. The snout gear has 3 pins, and the rotor gear has 3 pins. The coupler is what mates the whole unit together. Over time, the (not metal) coupler wears out, and the holes oblong.
The 3800 naturally misfires at idle. Those misfires, cause a momentary "stoppage" of the S/C, which causes the pins to slam against the coupler. The sound gets worse as the engine warms up. If you ever hear a knock from the upper engine area, put a stethoscope (or screwdriver) on the S/C and to your ear......

The coupler noise is one of a few, only a few sounds from an SC 3800 that makes one think sudden death is imminent.

One of the others is the alternator bearing. Ever heard one of those failing? Sheesh, I thought I'd spun a bearing.

Abaddon wrote:

That doesn't sound right to me. When you spin it, it should be relatively noise free. Yours is making a "zipper" type sound. Unless it's the video making some weird feedback.

The "zipper" sound is accurate, not an artifact. It sounds like it's coming from the pulley area, so maybe a bad bearing after all, unlikely though it may be?

Looking at ZZP vs Intense snouts, the Intense rebuild is radically cheaper?

ZZP

Intense

I don't understand why there's such a price difference, but the Intense rebuild isn't so bad, if that's what I need.

SC snout is off, sounds like the bearing is bad?

Here's a couple pics of the bolt holes -





With the front bottom bolt out (easily missed), I was able to pry the snout off using a crowbar against the accessory tensioner to break the snout loose. The snout was glued on pretty good, but nothing the crowbar couldn't handle.

I looked at the coupler and I bet it's already been changed, I can find no play in it at all. Unless it can't take extra boost, I see no reason to change it.