Dampner out of wack

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1930

1930

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Left the shop a bit early today so I had a few minutes to play before the monsoon set it.

This is my 86 rebuilt engine, been dying to see if the notches were off on the dampner ( slipped ) Sure enough they have slipped this much.

Not sure how many degrees this is, dosent look like much. Not sure how the scale is broken up. I see the 10 way below ( advanced ? )

Its a manual trans so I sorta expected it to be slipped a bit I guess.

I hate to just make another notch. I like to do things right and have them look factory. Any way of fixing this?

No its not the angle of the camera, it is the little line just below the 0 line.

I gotta wonder just how accurate that cheap little stamped steel indicator is as well?
 

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Oval out the mounting holes othe scale and realign it? Just a thought. You could leave it as is if you have a dial back timing light and just note that you need to adjust for this inaccurracy.
 
68gtxman said:
Oval out the mounting holes othe scale and realign it? Just a thought. You could leave it as is if you have a dial back timing light and just note that you need to adjust for this inaccurracy.
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I was thinking about it after making the post and remembered that the scale I am using on this engine is not the original one. The original I still have but tougher to read so I borrowed this one from an 84 parts truck I had a few months back. Maybe they are a bit different, prob. not but maybe I can loosen it and maybe there is a bit of play or I could modify it slightly.

Thanks for the feedback
 
Had the chance to look over the scale and each hash is = too two degrees so not much. I think Im going to pull the timing cover back off next and see where the marks are lining up on the chain.

Problem with this engine/reason I could never get it to run very well was a major lack of vacuum showing on the gauge. If I remember correctly I was only pulling 11 inches at idle.

Working with a gear-head over the phone our thoughts ( his expertise ) was leading toward the P.O.S aftermarket timing set was out of funk.

Id like to check for this, I know that it is part of degreeing the cam. I need to figure this out, did it once I believe quite a few years ago on a 340 but that has been long forgotten.
 
It looks to be 3 degrees wrong. Should we assume you used a piston stop to position the crank ?
 
RedFish said:
It looks to be 3 degrees wrong. Should we assume you used a piston stop to position the crank ?
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No I did not have the time today to make the piston stop. I dropped the arm down on my dial indicator ( as close to the base as possible=less deflection if there was any ) and measured it this way.

I will be doing it with the piston stop tool over the weekend
 
You checking with no backlash on the chain, ie no ccw correction? That looks pretty close for any slants damper....im actually making a spider girdle for my trigger wheel adapted damper. A 4 arm + bolted to the pulley holes and extending out to the ring. It will have its ends bent at a very short 90 and will sit in recessed drilled holes so it doesnt touch, but it wont allow the ring to spin either.
 
pishta said:
You checking with no backlash on the chain, ie no ccw correction? That looks pretty close for any slants damper....im actually making a spider girdle for my trigger wheel adapted damper. A 4 arm + bolted to the pulley holes and extending out to the ring. It will have its ends bent at a very short 90 and will sit in recessed drilled holes so it doesnt touch, but it wont allow the ring to spin either.
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Yes I was very careful with this. No backlash on the chain. No counter clockwise rotation.

The engines tight but once I get it to start spinning slowly I can keep it spinning ( very slowly )

After that you lost me but good luck on your project
 
I'd be interested to hear how you used your dial indicator. You cannot just "look for" the highest point of the piston, as it's nearly stopped for a few degrees at TDC

What you must do is use the indicator the same way as you would a piston stop.........that is, stop the piston at an arbitrary point BTDC, mark the damper, then stop the piston on the way down at the same height ATDC and make a second mark. Your true TDC is halfway between the marks

If you are simply looking for "highest point" with an indicator it could easily be "off" that far by your method.

Also, it just might be that the piston rocking a little in the bore will add a tiny amount of "Murphy" into the equation..............
 
67Dart273 said:
I'd be interested to hear how you used your dial indicator. You cannot just "look for" the highest point of the piston, as it's nearly stopped for a few degrees at TDC

What you must do is use the indicator the same way as you would a piston stop.........that is, stop the piston at an arbitrary point BTDC, mark the damper, then stop the piston on the way down at the same height ATDC and make a second mark. Your true TDC is halfway between the marks

If you are simply looking for "highest point" with an indicator it could easily be "off" that far by your method.

Also, it just might be that the piston rocking a little in the bore will add a tiny amount of "Murphy" into the equation..............
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Yes, I am going to do the 30 degree stop on both sides of the dampener and see where it lands. I do not have a timing tape. What can you suggest as a measuring device between the two marks?

I have very little overlap showing on the dampener but from what I am reading the dial indicator isnt accurate enough to show the correct amount of overlap.......this has me confused...... a precision measuring device that is showing me ( in the thousands of an inch ) the amount of overlap as I look at the dial isnt accurate enough?

I can literally see the dial indicator rise with the piston, I can see the overlap with the dial indicator ( and it is very minute ) and of course I can see piston drop.

Again I will put together the piston stop/set up the dial indicator as you suggest and measure it this way over the weekend at the latest ( cause what do I know ) but I am going to be shocked if it shows me a different location on the dampener than what I have showing here now.

Suggestions on a temp. timing tape would be appreciated.

I guess maybe I need to invest in one of those stick on deals but for the time being I do not have one.
 
I received this P.M from a member here explaining what I am still having a hard time believing/understanding but I know you guys know more than I do so I just have to accept. ...........


This has been explained to me before and I do understand the overlap concept I just have a hard time accepting it in this case. Again I will measure it the other way this weekend and I am hoping I can see a difference between what I have come up with here now..............

There is a "dwell" period at TDC. There is a small time before you hit TDC, the split moment when you are at TDC, and the small time after TDC. They will all look like TDC. Plus there is clearance in the rod bearing and the piston. That is why you pick a number greater than .015 of an inch and reverse direction. Like .030 going one way, then reversing and reaching the same number. The center is true TDC..................
 
We assumed Dads new dampner had the same TDC mark as orig 273. NOPE. So I was thinking the same thing you were with remarking it. I took 67Dart273's advice which is a good thing to do. Used a piston stop method to find TDC and marked the damper.
Then took measurements on damper (to get circumference of a circle)to make sure we were getting the right tape. Once you have circumference of the damper divide by 360(degrees in a circle) your answer should match the new timing tape. Installed new tape on the dampner....if I remember correctly, we were about 20* out from the TDC marks on damper!!

If it was me and my dampner had "spun" I would be buying a new one

For example, lets say dampner has 10" diameter right?
Formula for Circ=2 X 3.14 X Radius
so we have 2 X 3.14 X 5(radius is 1/2 of diameter)
so this works out to 31.40 inch circumference. Divide this number into 360. Which gives you 11.46* per inch on tape.

Hope this helps
 
4spdragtop said:
We assumed Dads new dampner had the same TDC mark as orig 273. NOPE. So I was thinking the same thing you were with remarking it. I took 67Dart273's advice which is a good thing to do. Used a piston stop method to find TDC and marked the damper.
Then took measurements on damper (to get circumference of a circle)to make sure we were getting the right tape. Once you have circumference of the damper divide by 360(degrees in a circle) your answer should match the new timing tape. Installed new tape on the dampner....if I remember correctly, we were about 20* out from the TDC marks on damper!!

If it was me and my dampner had "spun" I would be buying a new one

For example, lets say dampner has 10" diameter right?
Formula for Circ=2 X 3.14 X Radius
so we have 2 X 3.14 X 5(radius is 1/2 of diameter)
so this works out to 31.40 inch circumference. Divide this number into 360. Which gives you 11.46* per inch on tape.

Hope this helps
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That does help, I am looking for an alternative at this point to buying the tape cause Id like to measure it this weekend but Ill see what I can come up with if nothing else is suggested.
 
Perhaps search for a post titled redneck timing tape, believe it was from "crackedback"...it may be of help to you....it might have been "hillbilly timing tape"...did a quick search and could not find it but it is here....
 
I almost never use an indicator, prefer positive stops. A stop is more difficult on some engines, impossible on an L head. The whole idea is to get the piston "down the bore" to a point where any crank movement is going to make a BIG change in the piston position. This means the further down, the better.

For our purposes piston rock in the bore is miniscule. By the time you set timing, read the marks with the light, get your eyeball "off" and so on, add up all the errors, you will be off 1/2 degree or so, anyhow. So the piston clearance is almost transparent.

For measuring 1/2 way between, you can use whatever you can come up with. On the V8s it used to be easier for me, in some cases, to make the two marks, then rotate them "down" and jack up the car and crawl under and work upside down. Easier than "hanging" down and trying to deal with obstructions above.

You can carefully measure between your two temp marks with calipers, dividers, a graduated flexible rule, anything you can to get it accurate

HERE IS a simple way I cannot take credit:

Get a scrap of heavy paper / light cardboard, and CAREFULLY cut it so it's EXACTLY the same length as between the two temp marks. Then fold it in half!!!!! You should be able to go from each temp mark and they should be equal "to the middle."

If your old mark is correct, of course that is where it will be
 
Get a new dampner. Slant six dampners were notorious for slipping. The rubber ring debonds from the core,once this happens it will keep slipping. Eventually it will come apart. If it's running at the time, it could do some major damage. I had similar problems with mine and once I swapped it out I could separate the two pieces by hand.
 
# 2 Parts truck :

Spent a bit this A.M modifying a bar to fit the TDC tool, dropped screw of TDC tool down in the cylinder as far as it would go, made my mark, rotated engine opposite direction as far as it would go, made another mark.

Cut out a narrow strip of paper, cut it to length so that it was between the two marks I had made and then folded it in half and marked center.

The dampener here as slipped a whisper. The center mark of the paper falls onto the leading edge ( ATDC ) of the notch that is on the dampener.

I would say this is acceptable and nothing to give a second thought too. Does everyone agree?
 

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powerwagonpaul said:
Get a new dampner. Slant six dampners were notorious for slipping. The rubber ring debonds from the core,once this happens it will keep slipping. Eventually it will come apart. If it's running at the time, it could do some major damage. I had similar problems with mine and once I swapped it out I could separate the two pieces by hand.
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this is why i ended up with the romac... i was at a test and tune and my timing was ALL OVER THE PLACE. made some marks and it was spinning as much as 10* per run...
 
I don't agree with any balancer slip whatsoever. Not even a "whisper". Since even good SFI ones are pretty affordable, there's no excuse to run something that's damaged.
 
#1 Truck:

Performed same tests. This dampener was quite a bit off......It is off approx: the same 2 degrees that I had noted above in my first post using just the dial indicator but it is off instead ATDC wheres before it was off BTDC if I am using the correct terminology.

Is there a usual direction that these will spin?

I would guess there is only one way these things will typically spin but not sure of which way that would be.
 

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Why does it matter the direction of spin? It's a spun balancer. It should be replaced.
 
RustyRatRod said:
I don't agree with any balancer slip whatsoever. Not even a "whisper". Since even good SFI ones are pretty affordable, there's no excuse to run something that's damaged.
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#1 Truck: I am going to go ahead and put on the original timing tab/gauge and see if I get any sort of a different reading.

I see there are various versions of the slant dampener, I have yet to see another style identical to mine. Maybe it is because my engine is powering a 4 wheel drive truck? I do not know, I have two other dampeners out of similar year trucks that were two wheel drive and the dampeners match each other but not the one in my 86 4WD.

My engine also was originally equipped with a double roller timing chain as well like I have heard the industrial slants too of had. Maybe there is a different industrial dampener?

Where would I purchase a new dampener. I am not looking for cheap but instead a quality part. Rough price would also be helpful if you know. Thanks
 
Pioneer balancers are made by the same Australian company that makes Romac. I would just get a stock replacement Pioneer. They are good quality. A balancer is something that I would not be dickin around with. If I had any question about it whatsoever, I would throw it in the ditch and replace it. Think about this. If it slings off goin down the road. Where's it gonna go? It will destroy the fan and radiator. I have even seen one that took out the fan, transmission lines, radiator and indirectly the battery, battery tray and half the fender well. It wasn't purdy.

http://www.summitracing.com/parts/pio-da-2250/overview/make/dodge

...and I did not mean to sound like I was sayin you are dickin around with it. I simply meant it's THAT important a piece that if there's any question whatsoever, replace it, that's all.
 
RustyRatRod said:
Pioneer balancers are made by the same Australian company that makes Romac. I would just get a stock replacement Pioneer. They are good quality. A balancer is something that I would not be dickin around with. If I had any question about it whatsoever, I would throw it in the ditch and replace it. Think about this. If it slings off goin down the road. Where's it gonna go? It will destroy the fan and radiator. I have even seen one that took out the fan, transmission lines, radiator and indirectly the battery, battery tray and half the fender well. It wasn't purdy.

http://www.summitracing.com/parts/pio-da-2250/overview/make/dodge

...and I did not mean to sound like I was sayin you are dickin around with it. I simply meant it's THAT important a piece that if there's any question whatsoever, replace it, that's all.
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Thanks for clarifying ...............and I did not mean to sound like I was sayin you are dickin around with it..............

I am also an animal/cat lover. We have 4 not counting the strays we take care of.

Id still like to know if there is one direction these usually spin, I am curious if a direction has been noted as usual or un-usual.

I may take the advice given above and sent mine to dampner dudes. I tried calling but no answer. Anyone have any objections to going this route?

Ill have more pictures in a bit that might clarify
 
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