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Crank damper alignment

RestoreThemAll

Jedi Warrior
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I installed a crank dampener rebuilt by damperdudes on my BJ7 following the great advice from the BCF about heating to 275 degrees, adding little light oil on the crank and tapping it on. It did go on nicely. Yes, I wacked it a couple of times for the final seat.

I don't believe it's right though. It looks like it should go another 3/16" to 1/8" or so. For one thing the pulleys don't line up.

In the pic labeled "dampener all the way home" it looks like it should go on farther. Should the dampener be flush with the shaft shoulder in that pic?

In the pic "threads left on dog nut" it looks like the nut could go on further. Should it?

I measured the crank snout from the end to the oil slinger 1 1/8" and compared that to the depth of the dampener 1 5/16". The dampener is pressed on to the slinger. The timing gears line up perfectly. I must be missing something.

In the pic "dog nut lock washer" the lock washer is shown. It's not the same as the tab washer that came off. The washer came from AHspares. Here's a pic from the AH Spares web site. Is it just a different style lock washer?
https://www.ahspares.co.uk/austin-h...G595-to-ENG680/LOCKWASHER-crankshaft-nut.aspx

Lastly, my bently manual doesn't show a torque spec for a dog nut. Does anyone have that?

Thanks in advance for your thoughts.
 

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re: "... For one thing the pulleys don't line up."

All the evidence you need that something ain't right. It looks like you have the oil slinger outside of the seal; it should be inside. As far as a torque spec for the dog nut; I've always torqued as tight as I can (it's not likely you'll break the crank).
 
Bob,

I see what you're saying about the oil slinger and thought that at first. When I was laying out the parts in preparation of install I noticed that the lock washer is concaved similar to the oil slinger. So I looked it up on the AH Spares web site. One nice thing about that site is they provide great diagrams and pictures. The part that I have is clearly labeled lock washer. It matches up with the picture on their site. There is an oil slinger between the seal and the gear that's in place where it belongs. The oil slinger is a bit larger than the lock washer.

The pulleys are misaligned by an 1/8" give or take a little. I don't like it but I can't see a reason why.

The crank is in place. Can't mess that up, right?
Then shims to align the gear to the cam gear.
The gear next.
Oil thrower after the gear.
Timing cover with seal aligned to center the dampener.
Finally the dampener install.
The rest is described above.
Seems simple enough.

I'm concerned about the belt alignment but more so the dampener itself. I've read the experts on this forum who have warned about improper installation of the dampener. It's a critical component.

I'm still scratching my head about this one. I can't wait to get on to the body work. I'm much better at that stuff.
 
Update: Ron from Damperdudes was very helpful in sorting some of this out.
There are 9/16" of threads on the crank shaft available for the crank nut to capture. There are 13/16" of threads in the nut. If the washer is considered then 1/2" of threads secure the dampener. That should be OK, right?

The two pulleys, water pump to dampener, are misaligned by about 1/8" inch.
Pump: from the front engine plate to the center of pulley is 2”
Dampener: front engine plate to center of pulley 2 & 1/8”

Comparing the old pump to the new one
The old pump pulley measures 2 & 7/16” from the edge of pump body to the center of the pulley, new one 2 & ¼”.
So the new one does set back farther.
Is it possible that the pulley on the new water pump is pressed on too far?

Dale
 
Update: I've been working with AHSpares on the pulley alignment issue. Those guys are really great to work with. Very helpful. I replaced the water pump with a new one from AHSpares. The manufacturer pressed the pulley on the water pump about 1/8" too far. They're sending me a new one at their expense. The one I have now is junk, as the pulley can't be realigned without losing the friction fit.

My concurs manual says that the distance from the block to the edge of the pulley is about 2". AHSpares took several measurements from at least three different water pumps. They're all 2". Go measure your water pumps. Are you wearing out belts?

There were a few things going on, as explained above. I'm very pleased with the support from both vendors. Excellent service!

The last of this for me is the lock washer and torque spec. I'm going to clean up and use the original. That new concaved lock washer just doesn't seem right. I'm using a 3/4 drive socket ratchet. Without a spec I'll make it tight without striping threads???

Dale
 
Tighten it up to about 90-95 ft lbs and you'll be fine. The bad harmonics only come into play around 5900 RPM. That's when the damper can come loose and fret the crankshaft if not snugged up properly. We racers usually torque it to as much as 120-130 ft lbs and that's with an interference fit- high performance damper such as an ATI Superdamper. But that's because we rev our motors to as much as 7000 RPM.
 
We racers usually torque it to as much as 120-130 ft lbs and that's with an interference fit- high performance damper such as an ATI Superdamper. But that's because we rev our motors to as much as 7000 RPM.

I put a super damper on when I rebuilt my engine and my Healey guru says 120-130ft lbs and I was obviously not going to race mine.

:cheers:

Bob
 
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