harmonic balancer - mark at 40 deg btdc at TDC???
06-05-2011, 05:54 PM
#1
Thread Starter
Join Date: May 2011
Location: TX
Posts: 7
harmonic balancer - mark at 40 deg btdc at TDC???
Just bought a '94 cobra....harmonic balancer has been replaced recently by previous owner. I was trying to install a new distributor and following how-to:
1) I pulled #1 plug and cranked in a clockwise direction on the balancer bolt.
2) when I felt compression in cyl 1, I watched the dist rotor and when the rotor was at #1 mark on dist, it was at 40 degrees on the balancer????
I repeated this several times - cranked the engine over twice with the breaker bar (by twice, I watched the dist rotor rotate 2x around....I think that's correct....) to again align to TDC and same result. I also checked it at 1x around (in case i was off.....) and it was also at 40 degrees. It is aligned at 40, though....so I *could* use 40 as my zero mark and I do have a degree timing light.
Anyone experience this before? My last car that used a distributor and needed to be timed was my '69 camaro z28 (bought in 70's and sold in 70's), so this is a learning experience for me......
I'm reasonably sure I'm doing things right, but could be noob mistake, or can the balancer be simply installed wrong and be off that much? My understanding is that at TDC on the harmonic balancer, the rotor should be pointing at #1 sparkplug rotor location, but mine is more like the following ( How To: Properly stab your distributor. - MustangForums.com - first pic that says "this is incorrect"). Right now, car runs fine, so looking for answers/suggestions before I delve into this further.
1) I pulled #1 plug and cranked in a clockwise direction on the balancer bolt.
2) when I felt compression in cyl 1, I watched the dist rotor and when the rotor was at #1 mark on dist, it was at 40 degrees on the balancer????
I repeated this several times - cranked the engine over twice with the breaker bar (by twice, I watched the dist rotor rotate 2x around....I think that's correct....) to again align to TDC and same result. I also checked it at 1x around (in case i was off.....) and it was also at 40 degrees. It is aligned at 40, though....so I *could* use 40 as my zero mark and I do have a degree timing light.
Anyone experience this before? My last car that used a distributor and needed to be timed was my '69 camaro z28 (bought in 70's and sold in 70's), so this is a learning experience for me......
I'm reasonably sure I'm doing things right, but could be noob mistake, or can the balancer be simply installed wrong and be off that much? My understanding is that at TDC on the harmonic balancer, the rotor should be pointing at #1 sparkplug rotor location, but mine is more like the following ( How To: Properly stab your distributor. - MustangForums.com - first pic that says "this is incorrect"). Right now, car runs fine, so looking for answers/suggestions before I delve into this further.
06-05-2011, 07:17 PM
#2
Is the car not starting?
Let the piston come to the top of the compression stroke then install the distributor to where it is pointing at number one. The balancer should be around 0 if it hasn't slipped. I ususally try to get it at 10 degrees on the install. Looking at the engine from the front of the car, number 1 should be somewhere around 10 or 10:30 if using a clock for reference.
Next time you take the distributor out, find an intake bolt or plenum bolt or something that number one is pointed towards so you remember where it goes.
Let the piston come to the top of the compression stroke then install the distributor to where it is pointing at number one. The balancer should be around 0 if it hasn't slipped. I ususally try to get it at 10 degrees on the install. Looking at the engine from the front of the car, number 1 should be somewhere around 10 or 10:30 if using a clock for reference.
Next time you take the distributor out, find an intake bolt or plenum bolt or something that number one is pointed towards so you remember where it goes.
Last edited by TrimDrip; 06-05-2011 at 07:20 PM.
06-05-2011, 07:58 PM
#3
Thread Starter
Join Date: May 2011
Location: TX
Posts: 7
so I am not crazy...
when the distributor rotor points to #1, the harmonic balancer should be at 0......if that's true, then I think the balancer has either slipped or was not installed correctly - since the balancer is keyed, is this possible? That's what has me confused. Are there mutiple slots on the balancer normally where it could have been put in the wrong slot?
06-05-2011, 11:03 PM
#5
4th Gear Member
Join Date: Jul 2008
Location: alabama
Posts: 1,812
inspect the rubber if it sticks out anywhere it has slipped! thats the only way you could be getting your result if the car is running and running correctly! but to have slipped 40* you should be having other issues!
06-08-2011, 10:51 PM
#8
2nd Gear Member
Join Date: Jan 2006
Location: Colorado
Posts: 384
http://www.stangnet.com/mustang-foru...-balancer.html
This thread has a picture of a HB that shows three sets of timing marks. Note how 30 degrees lines up with zero. This would mean to me that you are advanced 10 degrees on the correct scale
This thread has a picture of a HB that shows three sets of timing marks. Note how 30 degrees lines up with zero. This would mean to me that you are advanced 10 degrees on the correct scale
06-09-2011, 11:29 AM
#9
M.A.D. Motorsports
Join Date: Jul 2006
Location: Indiana
Posts: 8,014
Why are you replacing the distributor? I would pull the balancer completely off and make sure that the key hasn't broke. DO NOT use a pulley puller to remove it!!! Use the correct tools. Also when it is removed you can also tell that you are at TDC because the key on the crank sits at 12o'clock. Just gotta be sure its the compression stroke....
06-09-2011, 11:46 AM
#10
4th Gear Member
Join Date: Jul 2008
Location: alabama
Posts: 1,812
Seems that something isnt right, get the balancer to 0* on the compression stroke and then drop in the distributor pointing at the number one plug (on the distributor cap) then you will have a total of about 30* of ignition timing to play with in both directions together! if it dosent crank then you have a problem internally!
Last edited by Venomantidote95; 06-09-2011 at 11:50 AM.
