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Question: I think my 99 6.5 might be 180 out after rebuild - it won't start up. I fixed the codes it was throwing. I may have the IP gear and the cam out 180. A) is there an easy way to check this without taking a bunch of stuff apart? B) if it is 180 out, how do I fix it?

Is it simply a matter of pulling the IP gear then rotate the pump and reinstalling the gear?

History - the crank snapped, I got a used short block and I did the rod bearings and rings due to minor rust in the cylinders, so the chain between crank and cam was not changed - still in original orientation. When I put the IP gear on, the dots were perfectly aligned with the cam gear. But it may not have been at TDC for #1 when I set it.

The other question - how do I static time it? I don't have a scanner other than my launch code reader.

Thanks for any help. G
 

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Question: I think my 99 6.5 might be 180 out after rebuild - it won't start up. I fixed the codes it was throwing. I may have the IP gear and the cam out 180. A) is there an easy way to check this without taking a bunch of stuff apart? B) if it is 180 out, how do I fix it?

Is it simply a matter of pulling the IP gear then rotate the pump and reinstalling the gear?

History - the crank snapped, I got a used short block and I did the rod bearings and rings due to minor rust in the cylinders, so the chain between crank and cam was not changed - still in original orientation. When I put the IP gear on, the dots were perfectly aligned with the cam gear. But it may not have been at TDC for #1 when I set it.

The other question - how do I static time it? I don't have a scanner other than my launch code reader.

Thanks for any help. G
A DS4 electronic IP needs the correct timing software to correctly set TDCO.
You can start with the KOKO procedure to get the IP within the ballpark: Question: - 1997 6.5 TD

If you cannot get access to a Tech II you'll need one of these three to do it properly.
  • '96-'00 OBD2 will need the Car Code, AutoEnginuity PC software and cable or AUTEL® MaxiDAS®, available on the net, all three service GM.
  • All 3 are very user-friendly, does everything the TECH2 does for engine and transmission test and control. All three connect to the USB port on a laptop computer.
 

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To check IP > Pull glowplug on number one and get engine on compression stroke on number one. The pump dowel pin will be at 12 O'clock if you look thru the oil filler tube hole, The harmonic balancer timing mark will be on TDC.

Try to find that in your Chiltons manual.
 

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To check IP > Pull glowplug on number one and get engine on compression stroke on number one. The pump dowel pin will be at 12 O'clock if you look thru the oil filler tube hole, The harmonic balancer timing mark will be on TDC.

Try to find that in your Chiltons manual.
Hi DieselPro,

Thanks for all your help in the past.

I'm trying to ascertain where the mark on the harmonic balancer should be if #1 is TDC. Pulling the glow plug and seeing if the piston is at the top of the cylinder is going to get in the ballpark, but that's going to be +/- 10 degrees or so, isn't it? (based on cos(<10degrees) still close to 1) What's the trick to know if the piston is really at TDC?

One of my trucks has a little indicator made of stamped steel with little pointers. The other truck, with the problem, does not, but when I align the IP pin to 12, the harmonic balancer line is roughly where that indicator is bolted on in the other engine. Seems like that's right, no? i.e. I'm pretty close?

The problem I'm having is that TDC (rising edge supposedly) from the crankshaft sensor is aligning about 45 or more degrees off from the low res optical sensor. I've tried it with two pumps now. The result of that is that the PCM is not able to time the inject signal ("A" to the PMD) appropriately and it's trying to fire the pump after the low res optical pulse occurs. Ordinarily it's supposed to do that about 1.7ms before the optical pulse, which is the nominal closing time of the fuel metering solenoid on the IP, and then remain on for 33degrees or so. I can't for the life of me figure out how things can be that mis-aligned (i.e. 45-60degrees vs 33 nominal). Could there be something funky with the crankshaft sensor? What's it looking at anyway?

Thanks!
 

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For some reason the crank sensor has been very sensitive on the 6.5. Aftermarket sensors aggravate the problem and should only be replaced with AC Delco. Using anything else causes all kinds of problems in some trucks. Highly suggest using the DieselPro Gremlin remover when trouble shooting odd problems. The 6.5 "shares" 5 volt reference signals and a faulty signal can ruin the signal of others. Please don't overlook the cam drive gear sprocket key which is a weak point on the 6.5.
 
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