Author Topic: timing issue  (Read 440 times)

Offline john h

  • Jr. Member
  • **
  • Posts: 206
timing issue
« on: February 07, 2019 - 01:22:13 pm »
Hi all,
I'm having an issue with my timing.  The car starts and runs fine but then it has a blip in the timing on a fairly normal interval.  This blip can be seen using the timing gun and it can be seen on the computer.  This was an issue back when it was carburated and I was running a new SB distributor with the new electronic ignition parts the crate motor came with and it's still an issue running EFI with a new locked out billet distributor with timing controlled by the EFI.  I have base timing set at 12* BTDC at start and Idol.  it will idol there and read 12 on the gun and on the handheld computer.  suddenly, it will blip, and bump to 16 or 18 and then go back.  the idol definitely changes and you can hear it in the exhaust if you are listening at the back.  I can't really say if I have the problem at speed but I don't think I do because the advance seems to have a more constant # on the handheld computer when I running at say 50 MPH or 2k RPM.  I also check it on the Timing light at 2k and it seems to be a non issue.  What could be causing this issue? do I need to worry about it?
John
73 Cuda
360 Crate motor
FiTech Fuel injection
727 Trans (wishing it had Over Drive)




Online 70chall440

  • Sr. Resident
  • ******
  • Posts: 5615
Re: timing issue
« Reply #1 on: February 07, 2019 - 01:50:00 pm »
If you had the issue with the previous distributor and now with the EFI and a new ignition system (or at least the distributor) you need to look at what has remained the same. On the electrical side, are you using the same coil? I suspect that your issues more mechanical in nature, meaning the timing chain/gears. I understand you have a crate engine but that doesn't mean there isn't an issue.

Should you be concerned? Perhaps, depends on what is doing it. If it is a timing chain problem then yes you should. Drop the oil and see if there are any metal flakes in it. If there is, then you need to pull the front of the engine apart, if there isn't you may not be out of the woods, but you need to keep looking. another trick is to use a stethoscope (or long screw driver) on the timing chain cover and see if you can hear any weird noises.

All that said, I would look at everything connected to the timing side that has carried over.
Current Mopar
70 Challenger RT 440-6 EFI, 73 Cuda 416-6 EFI
05 Hemi Durango, 01 Ram 4x4, 14 Ram 2500 4X4, 10 PCP Challenger 6 spd RT, 01 Viper GTS ACR, 52 B3B w/330 Desoto Hemi, 70 Hemi RR (under const)
Past Mopars
9 x Challengers. AAR Cuda, 4 RR, 2 GTX, 4 Chargers, etc... (too many to list)

Offline john h

  • Jr. Member
  • **
  • Posts: 206
Re: timing issue
« Reply #2 on: February 07, 2019 - 02:02:17 pm »
If you had the issue with the previous distributor and now with the EFI and a new ignition system (or at least the distributor) you need to look at what has remained the same. On the electrical side, are you using the same coil? I suspect that your issues more mechanical in nature, meaning the timing chain/gears. I understand you have a crate engine but that doesn't mean there isn't an issue.

Should you be concerned? Perhaps, depends on what is doing it. If it is a timing chain problem then yes you should. Drop the oil and see if there are any metal flakes in it. If there is, then you need to pull the front of the engine apart, if there isn't you may not be out of the woods, but you need to keep looking. another trick is to use a stethoscope (or long screw driver) on the timing chain cover and see if you can hear any weird noises.

All that said, I would look at everything connected to the timing side that has carried over.
That all makes sense.  I am using the same coil a blaster 2 coil and timing chain.  The plugs, wires, computer control and distributor all new. with using EFI timing control you eliminate the electronic spark box and the ballast.  I don't get any errors on the controller.  From time to time I do get a startup kickback when the engine is warm.  I wonder if the chain is stretching or sloppy and the timing is off at just at the moment I turn the key but I would assume that would advance the timing based on it idling at 12* and then bouncing up to 16-18*.
John
73 Cuda
360 Crate motor
FiTech Fuel injection
727 Trans (wishing it had Over Drive)

Online 70chall440

  • Sr. Resident
  • ******
  • Posts: 5615
Re: timing issue
« Reply #3 on: February 07, 2019 - 02:09:03 pm »
On the surface, it "sounds" like your chain is either sloppy loose or the gear isn't tight and wobbling around perhaps. I would swap out the coil first and see if that changes anything, that is the easiest thing to do before ripping the front of the motor apart. That said, if you do end up tearing it apart, do yourself a favor and spring for a timing chain tensioner when you put it all back together. I think Manicini sells them and they are awesome.
Current Mopar
70 Challenger RT 440-6 EFI, 73 Cuda 416-6 EFI
05 Hemi Durango, 01 Ram 4x4, 14 Ram 2500 4X4, 10 PCP Challenger 6 spd RT, 01 Viper GTS ACR, 52 B3B w/330 Desoto Hemi, 70 Hemi RR (under const)
Past Mopars
9 x Challengers. AAR Cuda, 4 RR, 2 GTX, 4 Chargers, etc... (too many to list)

Offline john h

  • Jr. Member
  • **
  • Posts: 206
Re: timing issue
« Reply #4 on: February 08, 2019 - 01:23:03 pm »
On the surface, it "sounds" like your chain is either sloppy loose or the gear isn't tight and wobbling around perhaps. I would swap out the coil first and see if that changes anything, that is the easiest thing to do before ripping the front of the motor apart. That said, if you do end up tearing it apart, do yourself a favor and spring for a timing chain tensioner when you put it all back together. I think Manicini sells them and they are awesome.
Thanks for the advice.  I have a stock coil I can try.  I will also pick up a stethoscope. 
John
73 Cuda
360 Crate motor
FiTech Fuel injection
727 Trans (wishing it had Over Drive)

Offline rusty dodge

  • Jr. Member
  • **
  • Posts: 298
  • 74 challenger 440-727-3:55
Re: timing issue
« Reply #5 on: February 10, 2019 - 09:01:00 am »
What about the tang at the bottom of the distributor shaft. Does it fit snug into oil pump gear slot? The slot may be worn. Is the rotor stationary, or is there play there?

Online 70chall440

  • Sr. Resident
  • ******
  • Posts: 5615
Re: timing issue
« Reply #6 on: February 10, 2019 - 12:40:06 pm »
This is a possibility as well, you changed the distributors but if the timing gear is slopped out it would exhibit the same problems regardless of distributor. Easy enough to check.
Current Mopar
70 Challenger RT 440-6 EFI, 73 Cuda 416-6 EFI
05 Hemi Durango, 01 Ram 4x4, 14 Ram 2500 4X4, 10 PCP Challenger 6 spd RT, 01 Viper GTS ACR, 52 B3B w/330 Desoto Hemi, 70 Hemi RR (under const)
Past Mopars
9 x Challengers. AAR Cuda, 4 RR, 2 GTX, 4 Chargers, etc... (too many to list)

Offline john h

  • Jr. Member
  • **
  • Posts: 206
Re: timing issue
« Reply #7 on: March 12, 2019 - 01:22:38 pm »
What about the tang at the bottom of the distributor shaft. Does it fit snug into oil pump gear slot? The slot may be worn. Is the rotor stationary, or is there play there?
I have not been able to look into this issue so far but I will for sure pull the cap and see if the rotor has any play.  The motor is a crate  engine and only has about 20K on it.   
John
73 Cuda
360 Crate motor
FiTech Fuel injection
727 Trans (wishing it had Over Drive)