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Discussion Starter #1
So, last week my 88 Quad developed a serious engine vibration. After looking on this board and asking a few people I determined it was a dying water pump. If it's not, well, hey, I'll have a new water pump!

Worked on it Sunday but stalled at the crank pulley nut. I got me a 36mm socket and today managed to remove the nut on the crank pulley. There was no tab to bend back as stated in the shop manual, but I needed an extension on the breaker bar to get it loose. Good advice elsewhere to put the car in 5th gear and chock the wheels. Also used copious amounts of PB Blaster. (That means lots of it.)

So anyone have a tip on pulling the pulley? Rubber mallet? C4? It is my last disassembly hurdle, and I don't want to hurt this key part.

While I'm in there, I am going to replace the alternator with a new (rebuilt) from Vick. Might save me a trip under the hood soon. I have had the car since July and really don't know what the PO might (or might not) have done. Also have a new thermostat. And some cool patches for my denim jacket.

Thanks!
-Phil
88 Quad
 

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If you have gotten the nut off, they you have completed the hard part of the operation. The crankshaft pulley pretty much just slides on. Tap it with a mallet, pry it with a big screwdriver - it shouldn't require a lot of effort. These pulleys are pretty beefy, so I don't think you will fracture or bend it - again, it shouldn't require that much force.

Note that I've never removed a pulley on an engine still installed in the chassis - I presume there's enough clearance between the front crossmember and the front cover.
 

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Discussion Starter #4
Thanks, Jay. I give it a shot (ha!) tomorrow.

Tifiosi - I hadn't really thought about it. I got the parts for the plan, but not more. I am anxious to get the thing back together, and have all the parts for the current job. Now that I have done a lot of it, I am not as nervous about having to do something like this again. And I have experienced situations where I fixed more than I needed to and mucked up things (not on a car, though). I was ambivalent about even doing the alternator, working on that theory, since the current unit seems fine.

Feature creep is a danger! I have trailing arm bushings that I will do soon, and the "while I'm at it" bug wants shocks and springs, too.

Thanks for your help. The more I do, the more I can contribute back to the forum.

-Phil

P.S: I sure hope the water pump was the problem!
 

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These pulleys are pretty beefy, so I don't think you will fracture or bend it - again, it shouldn't require that much force.
Agree - they are quite 'beefy' but they are also known for cracking at the keyway. Make sure any force you apply for removal is as straight 'off' as possible. Not a lot of sideways leverage.

If/when you do get it removed, inspect the hub - especially at the corners of the keyway slot - for cracks.
 

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P.S: I sure hope the water pump was the problem!
I'm trying to understand how a dying water pump would cause engine vibrations. Is the bearing so bad the pump's pulley is wobbling all about?

More likely to cause a vibration would be a broken fan blade (due to imbalance).
 

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Discussion Starter #7 (Edited)
I have a new fan, too. The old one didn't show any breakage, but I was strongly advised to replace it since we didn't know how old it was. The shroud was so brittle you could break pieces off with your fingers.
 

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Tifosi had written: "If you're gonna go as far as pulling the crank pulley and are in an preventative maintenance mode anyway, why not change the front seal while stuff is out of the road?"

This is good advice, but I think it would be hard to change the seal with the engine in the car. I'm sure that professional shops, with lifts, do this operation all the time. Still, as a home mechanic, I would be hesitant - there isn't a lot of room to work with the engine in the car. Also, the detail of the front seal mounting is a little odd - there is no lip at the back to stop the seal as you tap it in. It is possible to knock one edge in so far that it falls out the back of the hole. Installing a new seal is an easy operation to do on a disassembled engine, with the front cover on your workbench. It is pretty easy on an assembled engine sitting on a stand. But, in the car? I'd be cautious unless there was a severe leak.

Do check the smoothness of the sealing surface on the front pulley. A groove can develop there, as grit in the oil wears into it. If you find a groove, smooth it with fine emery cloth.
 

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Hmmm, I've had several 4-cyl. Alfa water pumps fail in the last few decades, but never felt any engine vibrations. The pulley will wobble a bit as the seal and bearings go, though, so hopefully that's your issue. Also never seen a bad pump that wasn't leaking. Is yours leaking, and/or can you feel any wobble in the pulley?
 

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Discussion Starter #12 (Edited)
If you run the engine with the fan belt removed is the vibration gone? If NOT, the problem lies elsewhere...
NOW you tell me. <grin>

I just put the alternator on. The screws are too short on three of the bolts to hold the wiring cover on. Not stopping me. First cigar lit, break time.

Now I gotta clean the crud off the front of the block. I'm thinking light emery. Maybe some WD, too.

Mistakes so far: 1) Didn't mark which belt was which (I have A/C which doesn't work). 2) I have a 10mm nut that is orphaned. 3) Not taking it to a competent mechanic.

ghnl - If it isn't the water pump, where else might the problem lie? (If it isn't the water pump, at least I won't have to worry about the water pump for a while!)

Thanks!
-Phil
 

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If it isn't the water pump, where else might the problem lie?
Well, the list is long...

Is the vibraton there at idle? Or only when you rev up the engine? When the car is moving or not moving?

It could be an ignition or fuel injection fault (running on three cylinders), a driveshaft fault (guibo breaking up/imbalance, bad U-joint). It is really hard to diagnosis over the 'net. Can you provide more clues?
 

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Discussion Starter #14
The engine vibrates at idle, out of gear. It isn't constant, but regular, cyclical. When it started, I pulled into a gas station and opened the hood. Under the flourescent lights, the fan apeared to "strobe" backwards when the engine vibrated. The engine feels and sounds good, and revs well. There also developed a metallic clank. The effect seemed to be diminished when I turned on the A/C.

Shortly before I noticed it, we had to brake hard for an idiot, but did not hit any bumps. The motor mounts are new (August) and appear sound. Also new are the rear tranmission mount and center driveshaft support, all replaced at the same time.

Thanks!
-Phil
 

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Have you removed the crankshaft pulley? If so, did you carefully inspect for damage/cracks of the hub near the key way? If you haven't removed the pulley, with the belts off, does the crank pulley wiggle at all (it shouldn't).

Peruse this thread - I hope it is NOT a cracked crankshaft pulley.
What the?!?
 

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Discussion Starter #16
I did remove the crakshaft pulley. It is back on, but only hand-tight. I'll take a look at it, but there didn't appear to be any issues with it.

There was only a thick, keyed washer under the nut. I have no oil leak in that area.

I'll re-inspect the pulley - better to find out now than out on the road somewhere.

That thread also had a nice engine-cleaning tip, with the Simple Green. I always wondered how those Ferrari guys got thier engines so clean.

I read in another thread that the crank pulley nut shold be tightened to 180 ft/lbs of torque. I guess I'll have to get a torque wrench!
 

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IIRC, Simple Green should not be left in contact with aluminum for a long while. So, if you do use it, be sure to wash it all off.

A torque wrench is a good tool to have. But for the crank nut 180 ft/lbs really means to use a large wrench and get it as tight as you can. A torque wrench that'd measure to 180 ft/lbs wouldn't be useful for the more typical tightening torques you'd use (say 65 ft/lbs for cylinder head nuts).

BTW, it seems there are two styles of keyed washers behind the crank pulley's nut. On our '84 I have the style that one bends up against a flat of the nut (after it is tightened) to prevent it from moving. I don't know how the other style works. Perhaps it is just a washer and you are supposed to use 'Locktight'?
 

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Discussion Starter #18 (Edited)
Simple Green - good for the environment, bad for aluminum.

I got a breaker bar to put the nut back on. The pulley is sound.

I can only seem to get it so tight befor the car moves. I have it in reverse with the wheels chocked. Should I use locktite or something? I would hate to have a loose nut there.

I was wrong about the washer - it is not keyed. But the pulley is.

Edit: in 5th gear, wheels chocked. Using 18 in. breaker bar with extension pipe, tightened it as much as I can pull. Good?

-Phil
 

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Using 18 in. breaker bar with extension pipe, tightened it as much as I can pull. Good?
Sounds good to me. If you apply 120 lbs of force to that 18" lever (the breaker bar), you'll be applying 180ft/lbs on the nut.
 

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Discussion Starter #20
Cool. Reassembly time!!!

I think I'll leave the A/C belt off, for now. Cooler weatrher, and the A/C doesn't work anyway.

If a) I got everything together right and b) this fixes the car, I'll call it the "Miracle of Spring Branch", and celebrate this day by donating to the board.

Thanks!
-Phil
 
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