crank trigger timing - Performance Forum

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crank trigger timing
Thursday, May 09, 2013 7:39 AM
Hello all. I'm currently in the process of building an le61 hybrid motor, LE5 bottom and l61 head. I have the motor all put together and in the car just having trouble getting it started. I have fuel and spark but it stumbles to start and occasionally backires telling me timing is way off.

I'm using the external crank trigger wheel mentioned on these boards for the swap but I'm obviously guessing since I mounted the crank sensor on the water pump access hole that I have everything off. I mounted the trigger wheel like it would be oriented on an l61 but I guess I need help positioning and timing everything.

I've looked at all the old threads here but none are very descriptive on how its all done. Looking for some help. Thanks in advance!

How I mounted the sensor


The trigger wheel mounted


Here if you look close you can see the small knotch on the back of the crank pulley to time it. The black mark I have on the wheel represents the key way in the crank





Re: crank trigger timing
Thursday, May 09, 2013 3:02 PM
Well, I can't see the timing mark on the crank to see where you have it, but basically you need to set your crank pulley at TDC..there is a hash mark on the timing cover that should align with the mark on the pulley..you can also verify by pulling the original CKP out of the block and see that the key way on the ring is indeed pointed at that sensor location. Now you know that is at TDC.

For the trigger wheel, you just need the reference tooth pointed at the external CKP (which is why it's irrelevant where the sensor is mounted)...all the sensor cares about is seeing that 7th "tooth" on the wheel.

curious, is this the m62 hybrid Hogar posted up on facebook? I recognize that green block lol.






Re: crank trigger timing
Thursday, May 09, 2013 3:54 PM
EVILution (KGMs FrankenCav) wrote:Well, I can't see the timing mark on the crank to see where you have it, but basically you need to set your crank pulley at TDC..there is a hash mark on the timing cover that should align with the mark on the pulley..you can also verify by pulling the original CKP out of the block and see that the key way on the ring is indeed pointed at that sensor location. Now you know that is at TDC.

For the trigger wheel, you just need the reference tooth pointed at the external CKP (which is why it's irrelevant where the sensor is mounted)...all the sensor cares about is seeing that 7th "tooth" on the wheel.

curious, is this the m62 hybrid Hogar posted up on facebook? I recognize that green block lol.

Maybe you need to clarify, because what you just typed is not even remotely true. All spark timing is based off of the precise location of the sync notch and the crank sensor. If you do not have this located correctly to the expected crank angle using an OEM PCM (or corrected for in a standalone EMS) , you will blow up an engine.




I have no signiture
Re: crank trigger timing
Thursday, May 09, 2013 7:57 PM
Lol why yes this is the one hoger posted on Facebook. I have the car all together just this is the last hicup I have left.

I know its very hard to see but in the last pic the hatch mark is close to the white x. So basically your saying line the 7th mark on the external wheel with the sensor when the motor is at tdc?



Re: crank trigger timing
Friday, May 10, 2013 7:17 AM
Richie Aranda wrote:Lol why yes this is the one hoger posted on Facebook. I have the car all together just this is the last hicup I have left.

I know its very hard to see but in the last pic the hatch mark is close to the white x. So basically your saying line the 7th mark on the external wheel with the sensor when the motor is at tdc?

Absolutely not. The link below explains how to time a 6+1 wheel for a GM 4cyl.

http://www.megamanual.com/ms2/GM_DIS.htm

The sync pulse is 70degrees after TDC of cylinder 1.




I have no signiture
Re: crank trigger timing
Friday, May 10, 2013 1:58 PM
Yeah, my bad, I don't know what the hell I was thinking. Been a while since I set mine up. Whalesac is correct using the 70*. Follow the picture in the link he posted. I'll still try to get a pic of mine later today or tomorrow morning.
Forget if I mentioned this on facebook, but I think you're going to have an issue using the stock pulley where your ckp is mounted...PJ made the same bracket and had to use an MRZ pulley since they are flat and don't have the "spokes" bow out like the stock one...where your sensor is, the "spokes" on the trigger wheel sit right on the "spokes" of the pulley and warp when you tighten it down. I mounted my sensor towards the bottom of the pulley to avoid this.






Re: crank trigger timing
Friday, May 10, 2013 5:32 PM
Ok so I got you guys now. Make the 7th notch 70* after the sensor with the motor on tdc.

I have the sensor mounted good and close to the external wheel. I know what you mean about the stock pulley being to big but I got around it just fine.

I appreciate the help guys. Gonna try it tonight and cross my fingers.



Re: crank trigger timing
Saturday, May 11, 2013 11:32 PM
Well put the motor at tdc on the #1 and degreed the wheel 70* from the sensor and...........no go. I'm definitely getting fuel but now I don't think I'm getting spark. It might be because of the spacing of the sensor but not quite sure yet. Brought home some tools and meters and gonna try and read the sensor as its cranking and also make sure I have power to the coil pack.

Getting a little discouraged. I thought for sure it wad gonna fire. Bummer!



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