Can someone tell me how the crank dampener ulley is assembled?

I have 92 with a serpentine belt closest to block and then 3 v belt pulleys. Are the v belt pulleys bolted to the serpentine part?

reason I’m asking is I’ve discovered my dampener is slipping and debating buying a new one or having it rebuilt. The ones I see online appear to just be the serpentine pulley part, does that mean I swap my v-belt pulleys over?

I had the dampener on my 6 liter rebuilt but had down time and so didn’t mind sending it off. But if I can buy a new one for my 92 I’d prefer that.

 

The alternator pulley, multi rib rather than true Serpentine (l think) is part of the crank damper itself, the V belt pulley is actually bolted to the damper and can be removed with the damper left in place. You do swap over existing pulley to new damper.
l rebuilt my own using a jig and polyurethane about 8 years ago and all has been good ever since.

 

The new dampers are cheaper than a rebuild service. We’re lucky to have them available for 1992! Yes, most of the pulley bolts onto the damper and is reused.

A few hints for swapping this out…. The “crank dog” is also bolted in, with two bolts. You remove that and the single large damper bolt is behind it. That single bolt is TIGHT. I’ve broken them free by jacking up the car, putting a breaker bar on, and letting the weight of the car down… but you need a way to hold the engine from turning! Usually I just take out the radiator and use an impact gun. The to pull the damper itself, but the center nut back in loosely. Reinstall the two bolt damper dog and over tighten it… that will draw the damper out and the dog is now hitting the crank bolt.

have fun!

 

The above insights are spot on. Removing the radiator would solve every hardship of this repair. And I didnt compute the "crank dog" when I was removing, i thought it was the bolt holding the whole assembly on (see tech tip below!). And it is true that the car will run fine with a failed dampener because the Marelli timing ring is bolted to the dampener which spins normally even after failure. When this fails, literally the only thing that is affected is the alternator. And that only sporadically because it eventually stops slipping upon warm up and higher Revs where it jams against itself.

The sign of my failed dampener was a squeal at start up, but it doesn’t sound like a belt squeal. I can’t explain it, but when you hear it, you’ll hear the difference.

I have a hot tech tip for anyone completing this repair. Mistake the v-pulley nut bolted to the pulley ("crank dog") as the crank dampener bolt and try and remove it and you will fail. The pulley nut is 7/8” (roughly) and LOOKS like it holds the pulley and dampener on, but is really just an add-on so a mechanic can spin the engine more easily.

how did I discover this? By forgetting what I’ve read previously on this site and my own experience and torquing the **** out of it tryinf to remove it. Thankfully I stopped and regrouped and came back to this site and realized that you have to remove the 7/8” (whatever that is in mm) pulley bolt assembly with its 2 13 mm bolts, plus 2 more 13 mm bolts holding the pulley on. Now the 3-belt v-pulley pulley will come off. Then you can (more) easily get to the crank bolt, which is 33 mm.

After trying to remove the 7/8” pulley bolt, which literally CANNOT turn, with the engine locked at the flywheel, the 150 ft lbs of the crank bolt feels like nothing. Ugh.

here’s a video of my failed dampener

 

Video

 

Watched the video, unless it was flipped, you are tightening the nuts instead of loosening them

 

Sorry, to clarify, video shows how the dampener has failed by separation, I shouldn't be able to turn that at all. .

 

I am also having issues with the four belts and only one 3 groove V pulley. I started looking at the alternator and other belts. The alternator belt is flat with parallel ribs and is on a seporat pulley from the main three V belt pulley bolted on the crankshaft. The forth pulley next to the crankshaft is being used for the alternator. Is that pulley actually the crankshaft damper? The pulley is loose, rotates (not at the same speed as the other pulleys), shakes from side to side and is noisy. What happened to my car? Should the car come with a 4 V slot pulley system on the crankshaft? Did the car come with a different serpentine belt system that the car would run on a 3 groove main crankshaft pulley? Where do I go from here? Attached are a few pictures.

 

Patrick,

I answered all that for you on Nov 21, and asked you to confirm the belt layout.

Repeated here:
Early cars came with 4 "V" belts, and a 75Amp Lucas alternator.

Later cars, around Late 1988ish BUILD DATE, went to a PK flat belt for the Alternator, leavung the front "pack" of 3 V belts the same as the earlier cars, and that Alternator was 100ish amps, from memory..

Your latest post in that thread NOW tells us you have a flat alternator belt, THANK YOU, and I have, again, answered Today in that thread.

Lots of info in here, as your market has New Dampers available, go get one.

 

Sorry you had to answer the question twice. If you can not get the drive pulley reattached to the crank pulley is it best just to purchase a new unit? How do you prevent the motor from rotating when changing the crank pulley?

 

The outer ring of damper is attached to inner ring of damper with bonded rubber. While some people have done a DIY replacement of the rubber, I think home vulvanizing is more than you should bit off right now. Just buy a new one from Amazon: MTC 7808 / EAC-9693 Crankshaft Pulley (Harmonic Balancer, Jaguar/Land Rover models) https://a.co/d/9EYUSit

To hold engine place…. Buy a flywheel locking tool. Alternatively, vice grips on flywheel (or flex plate, whatever you chose to call it). Unbolting the large center bolt is still difficult this way.

Alternatively, don’t bother holding engine still. Remove radiator. Use impact gun… inertia is enough to hold engine in place when using air tools.

 

Link that works!

 

Aussie way.

1) Remove the HT lead at the coil, prevents the engine from starting.
2) Remove that pulley pack from the front, 4 X 9/16AF headed bolts. These are NOT tight enough, normnaly, to cause engine rotation, BUT, PAY ATTENTION, just in case the Jag Gods are against you. If in doubt, read step 3.
3) Remove the tin pan under the flywheel/flex plate/whatever, and jam a tyre lever in the teeth to jam the engine. This OK for the 4 pulley bolts, and tightening the BIG bolt later, but NOT for undoing that sucker unless a rattle gun is used.
4) REMOVE that tyre lever when finished with the 4 bolts. Leaving it there could destroy that flex plate, and you will be a little bit upset.
5) Now for that BIG centre bolt. Make sure that tyre lever is OUT OF THE AREA. Socket on that BIG bolt head 7/8, 15/16, I forget, and a 2ft breaker bar. End of said breaker bar sitting on the concrete floor, on the LEFT side of the the engine (as identified when sitting in the car facing forward). Take the car keys from your pocket, and insert in the switch, and turn to ONLY JOLT the starter motor. You only need to "quick flick" to the start position. That will rotate the engine, the breaker bar will tap the concrete, and the BIG bolt will loosen just fine.

First time is kind of scary, thats why we drink lots of beer down here, calms the nerves. I have used that method since 1968, and only had one actually start on me, coz I forgot #1, duh

Tightening that BIG bolt. Same socket/breaker bar, slide the floor jack tube over the bar, tyre lever in place under the car, and HEAVE in ONE smooth pull..

 

Grant
LOVE it!

 

Grant you are full of great information (and others)! the entire engine is covered in oil so I am cleaning large areas when I am working on something. Should all of the motors and pumps mounted on the front of the engen have the seals replaced at the same time as the main crankshaft?

 

I think we are now digressing from the original thread just a tad. Anew thread might be FAIR and smart.

Simple answer NO.

Read my oil leak sticky and think carefully, is it engine oil, steer oil, A/C oil, etc etc. Dont re-invent the wheel, its aleady as good as it will ever get.

 

Thanks I don't want to do any more work than I have to.

 

Personally I'm rather tolerant of oil leaks. Others are not.

However, being tolerant has its limits. Oil dripping (or being slung) onto hoses and belts will saturate the rubber and turn 'em soft-n-gooey....with failure soon to follow. At that point you fix the leaks..... or give the hoses and belts a wiping-down from time-to-time.

Cheers
DD