1998 V6 5-speed ext cab questions

[TBizzle98]

Sorry. I just posted a new thread to the "Silverado" forum by mistake.

I was asking about the timing on my 4.3L in my '98 1500. I scanned it a year or so back and it showed to be fine everywhere except the timing. It was showing a reading of -14 degrees. Obviously that is a pretty considerable amount, but there is no adjustment that can be made. I am thinking of replacing the timing chain in the truck. I'm not an expert on these computerized systems or anything, but is there anything I am not "in the know" about with this kind of job at hand?

I am also considering doing an engine swap. I am thinking of stuffing a 350 Vortec back in place of this V6. I'm sure I'm not the only person to ever consider that kind of swap, but what does it consist of electronically? I am not sure what pieces I will need to gather before I attempt such a task? I am almost to 150,000 on this motor and it is time to think about a solution to a potential problem since this V6 is bound to get tired soon.

[J-Ri]

Originally Posted by TBizzle98

Sorry. I just posted a new thread to the "Silverado" forum by mistake.

I was asking about the timing on my 4.3L in my '98 1500. I scanned it a year or so back and it showed to be fine everywhere except the timing. It was showing a reading of -14 degrees. Obviously that is a pretty considerable amount, but there is no adjustment that can be made. I am thinking of replacing the timing chain in the truck. I'm not an expert on these computerized systems or anything, but is there anything I am not "in the know" about with this kind of job at hand?

I am also considering doing an engine swap. I am thinking of stuffing a 350 Vortec back in place of this V6. I'm sure I'm not the only person to ever consider that kind of swap, but what does it consist of electronically? I am not sure what pieces I will need to gather before I attempt such a task? I am almost to 150,000 on this motor and it is time to think about a solution to a potential problem since this V6 is bound to get tired soon.

That timing is probably ok. Does it run good? You don't need to replace the chain at such low miles. My timing chain's got 170,xxx miles on it and the timing is still dead-on. I've got the 350ci, but it's the same engine, just two more cylinders.

For the engine swap, you'll need a new computer, and possibly different sensors. Your best bet would be to buy the engine and computer from a junk yard. Take everything electrical off the junk truck and swap it over to yours. I would have the engine rebuilt before you put it in, no matter how low the miles are on it.

[777stickman]

The tiiming you are reading is "computer controlled" timing from the VCM. Base timing can only be checked and set with a scanner capable of getting into the "cam offset" or "cam retard" mode. Base timing should be set at 0 +/- 2 degs.

[J-Ri]

Originally Posted by 777stickman

The tiiming you are reading is "computer controlled" timing from the VCM. Base timing can only be checked and set with a scanner capable of getting into the "cam offset" or "cam retard" mode. Base timing should be set at 0 +/- 2 degs.

Isn't there a connector you unplug to tell the computer to revert to base timing, then you can check it with a timing light? On the older ones, there was a tan(?) wire on the passenger side with a spade type inline connector that you unplug. Sometimes under the hood, sometimes on the inside against the firewall under the HVAC stuff. But they may have stoped that with OBDII.

[777stickman]

Originally Posted by J-Ri

Isn't there a connector you unplug to tell the computer to revert to base timing, then you can check it with a timing light? On the older ones, there was a tan(?) wire on the passenger side with a spade type inline connector that you unplug. Sometimes under the hood, sometimes on the inside against the firewall under the HVAC stuff. But they may have stoped that with OBDII.

The OBDII does require the scanner to set timing. Also need to add the RPM's must be at or greater than 1000 when setting the timing.