Balancer is "friction welding"

joespanova · 08-22-2011, 02:15 PM

Quote:

Originally Posted by Sean Marconette

Just curious, how long is it sitting on the limiter? That could also be a problem with a load/unload condition.

Sean

Not long , I purposely try to avoid that..........in fact I prefer "pro tree" style index racing ( 6.0 ).

I have always been skeptical of 2 steps and this may seal the deal as far as I'm concerned...............

any body know what kind of rev limiters they use in Pro Stock?

Alan Roehrich · 08-22-2011, 02:46 PM

Joe,
Given what you have posted, I'd say that the problem is that the balancer is past due for a rebuild and has long since ceased to function as a harmonic damper.

First, the elastomer o-rings in the damper will eventually fail due to age, exposure, and thermal fatigue. That is why the balancer should be returned for a rebuild at or before the suggested interval. Honestly, for what ATI charges for an inspection and rebuild, 2 to 5 years is a much better interval, and money well spent. Earlier return for inspection and overhaul can even allow ATI to tell you if your damper is the right one for your application, and if it is performing properly.

Second, if the balancer is moving on the crank, it is no longer absorbing and damping the harmonics. It is obvious that the damper is moving on the crank, that is why it is attempting to weld itself to the crank and the crank gear of the timing set. The most likely cause for this is the lack of a timely rebuild (the decal says "return every ten years for rebuild") has cause the damper to stop working, and once it stopped working, it worked itself loose.

ATI will step up and take care of your damper. They'll either rebuild it for a low price (I'd suggest a new hub, properly sized to your crank snout) or offer you a new balancer at a reduced price. Their service and support after the sale is excellent about 99% of the time.

Solving your balancer problems will probably solve the rest of your problems, as the timing set and valve train problems are most likely the result of the balancer no longer absorbing and damping the harmful harmonic vibrations. Those harmonic vibrations, if they are not absorbed and dampened, have to go some where. The logical place for them to go is into both the crankshaft, and through the timing set into the valve train. You are seeing the expected results of this in the damage done to your engine.

I do not think that the rev limiter is the cause of your problems. However, the rev limiter probably did make your problems worse. The combination of adding a rev limiter that you use on every pass to an engine with a balancer that was at the end of the life cycle between rebuilds is what you're seeing.

I seriously doubt the pushrods had any real effect, other than the stiffer pushrods may have transmitted more of the harmonics not absorbed by the tired balancer to the rest of the valve train. Weight of valve train components on the lifter side of the rocker fulcrum is negligible in comparison to weight on the valve side of the fulcrum. The stiffer pushrods are a good thing, don't take them out. Solving your balancer problems will likely solve the valve train problems as well.

C and W Racing · 08-22-2011, 03:54 PM

I don't remember the specifics, but in the National Dragster months back, Rhear Morrison talked about engines and the use of two steps. If I remember correctly ( which is questionalble) it was talking about the damage it causes when using a two step on a burn out. May be worth trying to find the article and read it to see if anything pertains to your situation.
Chuck

Jim B · 08-22-2011, 04:31 PM

joespanova you have a PM

joespanova · 08-22-2011, 05:36 PM

Alan , and all....thanks for the replies.

I called ATI ( Dave ) in tech and discussed this with him.

He was adamant that the balancer was way over due for an over haul for several reasons.

One of the reasons is that when new that balancer is only designed for an operating range below 8000 with the o'rings that come in it ( durometer ) . So it will be sent in and set up for what I am doing for as suggested by Alan a very reasonable cost.

I did not go into the 2 step with him other than to mention I now use one.......regardless he is very sure its all balancer related.

Alan Roehrich · 08-23-2011, 02:32 PM

Joe,
Very glad I could help. I've actually seen this a couple of times recently and been through it myself. Glad to pass on what I learned to help others.

08-22-2011, 02:46 PM	#2
Alan Roehrich Veteran Member Join Date: May 2006 Location: Murfreesboro TN Posts: 5,116 Likes: 1,573 Liked 1,832 Times in 415 Posts	Re: Balancer is "friction welding" Joe, Given what you have posted, I'd say that the problem is that the balancer is past due for a rebuild and has long since ceased to function as a harmonic damper. First, the elastomer o-rings in the damper will eventually fail due to age, exposure, and thermal fatigue. That is why the balancer should be returned for a rebuild at or before the suggested interval. Honestly, for what ATI charges for an inspection and rebuild, 2 to 5 years is a much better interval, and money well spent. Earlier return for inspection and overhaul can even allow ATI to tell you if your damper is the right one for your application, and if it is performing properly. Second, if the balancer is moving on the crank, it is no longer absorbing and damping the harmonics. It is obvious that the damper is moving on the crank, that is why it is attempting to weld itself to the crank and the crank gear of the timing set. The most likely cause for this is the lack of a timely rebuild (the decal says "return every ten years for rebuild") has cause the damper to stop working, and once it stopped working, it worked itself loose. ATI will step up and take care of your damper. They'll either rebuild it for a low price (I'd suggest a new hub, properly sized to your crank snout) or offer you a new balancer at a reduced price. Their service and support after the sale is excellent about 99% of the time. Solving your balancer problems will probably solve the rest of your problems, as the timing set and valve train problems are most likely the result of the balancer no longer absorbing and damping the harmful harmonic vibrations. Those harmonic vibrations, if they are not absorbed and dampened, have to go some where. The logical place for them to go is into both the crankshaft, and through the timing set into the valve train. You are seeing the expected results of this in the damage done to your engine. I do not think that the rev limiter is the cause of your problems. However, the rev limiter probably did make your problems worse. The combination of adding a rev limiter that you use on every pass to an engine with a balancer that was at the end of the life cycle between rebuilds is what you're seeing. I seriously doubt the pushrods had any real effect, other than the stiffer pushrods may have transmitted more of the harmonics not absorbed by the tired balancer to the rest of the valve train. Weight of valve train components on the lifter side of the rocker fulcrum is negligible in comparison to weight on the valve side of the fulcrum. The stiffer pushrods are a good thing, don't take them out. Solving your balancer problems will likely solve the valve train problems as well. __________________ Alan Roehrich 212A G/S Last edited by Alan Roehrich; 08-22-2011 at 02:49 PM.

08-22-2011, 03:54 PM	#3
C and W Racing Senior Member Join Date: Jul 2007 Posts: 557 Likes: 6 Liked 13 Times in 3 Posts	Re: Balancer is "friction welding" I don't remember the specifics, but in the National Dragster months back, Rhear Morrison talked about engines and the use of two steps. If I remember correctly ( which is questionalble) it was talking about the damage it causes when using a two step on a burn out. May be worth trying to find the article and read it to see if anything pertains to your situation. Chuck

08-22-2011, 04:31 PM	#4
Jim B Member Join Date: Dec 2008 Posts: 100 Likes: 0 Liked 1 Time in 1 Post	Re: Balancer is "friction welding" joespanova you have a PM

08-22-2011, 05:36 PM	#5
joespanova Senior Member Join Date: Jun 2011 Location: Ga. Posts: 521 Likes: 7 Liked 13 Times in 11 Posts	Re: Balancer is "friction welding" Alan , and all....thanks for the replies. I called ATI ( Dave ) in tech and discussed this with him. He was adamant that the balancer was way over due for an over haul for several reasons. One of the reasons is that when new that balancer is only designed for an operating range below 8000 with the o'rings that come in it ( durometer ) . So it will be sent in and set up for what I am doing for as suggested by Alan a very reasonable cost. I did not go into the 2 step with him other than to mention I now use one.......regardless he is very sure its all balancer related. Last edited by joespanova; 08-22-2011 at 05:43 PM.

08-23-2011, 02:32 PM	#6
Alan Roehrich Veteran Member Join Date: May 2006 Location: Murfreesboro TN Posts: 5,116 Likes: 1,573 Liked 1,832 Times in 415 Posts	Re: Balancer is "friction welding" Joe, Very glad I could help. I've actually seen this a couple of times recently and been through it myself. Glad to pass on what I learned to help others. __________________ Alan Roehrich 212A G/S