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1stuhess
07-04-2012, 09:20 PM
I am rebuilding a 1963 Avanti R2 and have come to the part of installing the Harmonic Balancer on the crank shaft. It went on really tight and my question is, how do I know when it is on all the way?

Skybolt
07-05-2012, 01:58 AM
What is really tight? Are you following the shop manual as to torque specs? For the standard virbation dampener it's 130-140 foot pounds of torque. For your R series I'm not familiar but "tight" is relative and not adequate for any engine assembly. If you have allowed for specified thrust and done all other assembly procedures according to the shop manual specs then the "harmonic balancer" will be done accordingly.

Please supply more detailed information as to your torque procedures so we may help determine if you have achieved you required results.

Did you ever get the shop manual? If so, then you just have to follow procedures like the rest of us and trust your torque wrench.

PlainBrownR2
07-05-2012, 03:54 AM
When I had my standard V8 damper off, the rubber and it's damper were "keyed" to the hub. If I recall, I think that bolt was to indicate TDC on the V8's. One of those bolts was offset from the rest, so the rubber mount and damper went on only one way. If it was correct, the rubber and damper slid onto the bolts with ease on the hub, and slid all the way to the front face on the crankshaft hub. If it was wrong, the rubber would distort, and the damper wouldn't fit right. It took some time to rotate the rubber around the bolt arrangement before it properly slid over the bolts. After I did that, I also had to rotate the pulleys around so they would coincide with the bolt arrangement on the hub as well. I had to pull the damper loose to install a modified trigger wheel ring behind the damper. Once I got the damper and pulley's back on, the large nut was installed, the engine was locked from rotating, and the nut was torqued to a preset value according to the shop manual. If it's not torqued to spec, the damper and pulley's could rattle and fly loose from engine.

I've never had the R series harmonic balancer on my Lark off, but aren't those things supposed to be "keyed" in the same manner? If that's the case, those should easily slide all the way back on the bolts to the front face of the crankshaft hub, if everything is aligned correctly. Also, don't forget to torque them to spec as well.

Dan Timberlake
07-05-2012, 07:00 AM
If the balancer/damper hub is the common (but not universal) design using about 0.001 inch enterference fit between bore and crank snout I'd expect the damper to move continuously at some fairly high percentage of the factory specified torque, then when the damper finally seats against the timing gear, etc the torque will rise very suddenly.
There are exceptions. The first Chevy small blocks used a pretty heavy interference fit only, and had no damper bolt, and were a real pain to install with a big hammer. They wised up and added a damper bolt, but some Chevy V8 dampers need full torque delivered with an impact wrench to seat. Some Other GM makes of that era used a slip fit and a big bolt tightened to triple digit lb-ft. As of my 90s vehicles slip fits and big torque are pretty standard. There are plenty of internet stories of cranks ruined because the damper was not torqued properly tight.

Hubs on shafts that transmit varying loads ( practically every component in a car's powertrain) won't last long if they used a simple keyed connection. The varying loads create micromotions that will create signficant wear in a few million cycles ( just a few days, even at 800 rpm, like a tire on the highway) . So they either need an interference fit with the shaft, or powerful axial clamping. 3rd string Junior varsity attachment methods like keyed slip fits and even a few setscrews have extremely low capacity and are just too unreliable for anything but screen door handles and consumer grade lawn equipment.

bezhawk
07-05-2012, 08:04 AM
I've never had the R series harmonic balancer on my Lark off, but aren't those things supposed to be "keyed" in the same manner? If that's the case, those should easily slide all the way back on the bolts to the front face of the crankshaft hub, if everything is aligned correctly. Also, don't forget to torque them to spec as well.[/QUOTE]

The R series engines are a different animal when comparing dampeners to standard V8's. The R engines dampener has an outer inertial ring (dampener) vulcanized to the inner hub.
The inner hub is tapped and the pulley bolts go in from the front . It is keyed like regular V8's and still has the center bolt that needs to be torqued properly.
Do not leave off the french lock, the bolt wont stay tight by itself, and if it works loose you will ruin your crankshaft. (the key will wear, and you'll get a heck of a knocking noise)

1stuhess
07-05-2012, 08:10 AM
It was a new dampner supplied by the machine shop who rebuilt the motor.I started the dampner on the crank with the key aligned and pressed it on by using the crank shaft bolt and an impact. It went down until the bolt bottomed out at which time I was concerned about how far it should go because it was still sticking out a ways. After reading the shop manual i discovered that there is a tool for pressing this on which I do not have and it was all ready on anyway. I installed the lower pullys which are quite thick and ran the whole thing down again with the impact. It went in some more and stopped. The dampner and pullys are not flush with the end of the crank as I have seen on other motors but it does'nt want to go any more. I am assuming that it has bottomed out on the timing gear. Is this where it is supposed to be and is there any way that I could have damaged any thing by using the impact gun like putting to much pressure on the timing gear.

Skybolt
07-05-2012, 11:30 AM
Is the crankshaft original to the engine? Studebaker had different length from snouts on the crankshafts which necessitated a different length hub/pulley bolt. You may have a short snout with a long bolt combination. Your R series should have come stock with the long snout crank if I'm not mistaken. Since you are building an R2 one would think only a long snout could be used. Just one of many possibilities. Do you have all the pulleys on?

Dan Timberlake
07-05-2012, 11:43 AM
It was a new dampner supplied by the machine shop who rebuilt the motor.I started the dampner on the crank with the key aligned and pressed it on by using the crank shaft bolt and an impact. It went down until the bolt bottomed out at which time I was concerned about how far it should go because it was still sticking out a ways. After reading the shop manual i discovered that there is a tool for pressing this on which I do not have and it was all ready on anyway. I installed the lower pullys which are quite thick and ran the whole thing down again with the impact. It went in some more and stopped. The dampner and pullys are not flush with the end of the crank as I have seen on other motors but it does'nt want to go any more. I am assuming that it has bottomed out on the timing gear. Is this where it is supposed to be and is there any way that I could have damaged any thing by using the impact gun like putting to much pressure on the timing gear.

Sounds like something is wrong. I'd pull it apart and measure everything.
The crank snout should always be a little below the damper/hub face. Otherwise the bolt and washer hit the crank first, and the hub will not be clamped axially, which is absolutely necessary.
Late V8 cranks (60s?) have longer snouts, so the early hubs etc stop flush with the crank before they touch the gear etc. I had to get a few extra parts (bolt and hub?? from the parts book) to seat my 259 damper properly. As-assembled, using mis-matched parts by another ignoromnibus the crank had scary visible (over 0.09" ?) endplay when prying gently on the damper, which was my clue something was wrong.

Can you see or measure a few thousandths of daylight above the key?
An improper key can be taller than the keyway cut in the hub, and can break an iron hub if forced together. More of a problem with a Woodruff key
http://motionsystemdesign.com/images/too-tall-key.jpg
http://www.classicinlines.com/images/pics/CrackedHub.jpg

1stuhess
07-05-2012, 12:25 PM
The crank is original to the motor. I think that it is all the way on now but I was hoping to find some one who could give me some kind of measurement from a point a to point b (block to back of dampner or simular) just so I could compare it against mine to ease my mind.

1stuhess
07-05-2012, 12:27 PM
The pulleys are on and appear to line up with the water pump pulleys, not exactly but very close (within an 1/8 of an inch of each other).

PlainBrownR2
07-05-2012, 02:32 PM
Hubs on shafts that transmit varying loads ( practically every component in a car's powertrain) won't last long if they used a simple keyed connection. The varying loads create micromotions that will create signficant wear in a few million cycles ( just a few days, even at 800 rpm, like a tire on the highway) . So they either need an interference fit with the shaft, or powerful axial clamping. 3rd string Junior varsity attachment methods like keyed slip fits and even a few setscrews have extremely low capacity and are just too unreliable for anything but screen door handles and consumer grade lawn equipment.


Not that kind of keyed. In this case, Studebaker offset one of the bolts in the bolt arrangement on the standard V8 dampers, so to bolt on the rubber cushion and metal plate, required aligning the offset bolt arrangement on the hub, to the offset bolt arrangement in the rubber cushion and the damper. If the alignment is incorrect, it won't slide on, rather people will force it on, resulting in an improper fitting cushion, or tearing the rubber cushion. If you hold up the cushion and the damper, you can see the offset bolt arrangement where it attaches to the hub.

1stuhess
07-05-2012, 08:27 PM
Thanks for all the info, I think I've got it now.

Dan Timberlake
07-06-2012, 11:47 AM
Not that kind of keyed. In this case, Studebaker offset one of the bolts in the bolt arrangement on the standard V8 dampers, so to bolt on the rubber cushion and metal plate, required aligning the offset bolt arrangement on the hub, to the offset bolt arrangement in the rubber cushion and the damper. If the alignment is incorrect, it won't slide on, rather people will force it on, resulting in an improper fitting cushion, or tearing the rubber cushion. If you hold up the cushion and the damper, you can see the offset bolt arrangement where it attaches to the hub.

Hi PlainBrown,

Sorry for any confusion. My interference or axial clamping comments were about the damper hub to crank attachment.
(or gear to cam, or rear hub to axle, or flywheel to crank, or ring gear to diff carrier, or wire wheel to axle, etc, etc)

Dan T

PlainBrownR2
07-06-2012, 05:29 PM
Not a problem :cool:...

But, just for posterity's sake, and so everyone sees what I'm talking about, this is the photo of the standard 289 damper I pulled from the '55 to install the trigger wheel.

From the front:
http://i158.photobucket.com/albums/t102/PlainBrownR2/55%20Studebaker%20Commander%20Streetrod%20Project/EDIS%20Distributorless%20Ignition%20Setup/P1050146b.jpg

This is the damper as you would see it from the front of the car, when everything is mounted to the crank hub. As you can see in the photo, that bolt hole and rubber mount, as well as the crank hub and associated pulleys, have an offset bolt hole compared to the other ones in the crank hub. If everything is lined up correctly, that standard damper and rubber should just slide onto the crank hub. If it's not, the rubber will not slide onto the crank bolts, and the rubber will not slip into the damper very easily. This something that has to be paid attention to when assembling the dampers on the 259/289 standard V8's, and it is very easy to miss if somebody is putting the front of the lower assembly in a hurry. In effect, the crank hub bolt arrangement makes it keyed, so there's only one right way to install the rubber and damper :eek:.

I needed to pull the damper off, so I could put my trigger wheel on the rear :cool:.....

From the rear:
http://i158.photobucket.com/albums/t102/PlainBrownR2/55%20Studebaker%20Commander%20Streetrod%20Project/EDIS%20Distributorless%20Ignition%20Setup/P1050147.jpg

DEEPNHOCK
07-06-2012, 07:58 PM
John...
He said he has an Avanti R-2, which is a bonded ring type harmonic balancer...

PlainBrownR2
07-06-2012, 08:17 PM
I know, I know :). I just had to get my point across between the the terms keyed, keyed, and keyed to make sure everybody is on the same page. Like so many times before, my explanations seem to get misinterpreted in a rather major fashion, so I have to go back and explain it a few more times so everybody understands it :rolleyes:. Hopefully now everybody knows, lol....

SN-60
07-07-2012, 08:45 AM
To: 1stuhess,----- I've seen tight fits similar to the one You're describing here when the original parts are not put back together. In other words, if You install a 'replacement' Avanti damper on the original crankshaft, or
vice-versa.

sweetolbob
07-07-2012, 09:37 AM
If I missed this in the post, let me apologize but if you remove and reinstall the balancer, go to your local FLAPS and rent (for Free) a harmonic balancer installation kit. Driving the balancer on with a bolt and impact driver are a great way to learn how to install a helicoil to replace the threads that no longer hold the bolt. JMO

Bob