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Discussion Starter #1
First time user and appreciate any feedback.
I have a 1992 GMC Sonoma with the 2.5 L 4 cylinder with 5 speed manual approx 140,xxx miles.
Recently, while idling on warm up the engine completely quit in my driveway.
No spark was identified at the plugs or coil. I took the cap off and to check contacts and electrical connections.
I installed a new ignition coil, cap and rotor. Still no spark.
After trouble shooting, I see the rotor is not moving while cranking the motor. Any ideas? Broken distributor shaft or timing cam gear in the bottom?
I bought a new distributor however the old one has been a "bear" to get out after removing the clamp assembly.
I know it's an old truck with rust cancer but I like to get the Iron Duke back on the road.

Thank you for insight on the old 2.5 L.
 

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Discussion Starter #4
Any suggestions on removing distributor? I loosened the clamp and bolt from the distributor shaft. I suspect where the aluminum and cast iron meet feels like a tight bound. I sprayed PB Blaster around the base and let it sit for a few days. I tapped it with a rubber mallet several times to no avail. The distributor sits on a funny angle located in the back firewall.
Better access by removing the front passenger's tire to get to distributor.
Thanks for replying.
 

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Boozebag
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9,041 Posts
Do not pull the distributor. It's the camshaft timing gear. I have never seen a distributor drive fail, although it is a faint possibility.
The cam gear is made with phenolic resin and can fail right about the mileage you posted.

Don't replace any more ignition components... Waste of pesos

A Chevy 250 6 cylinder aluminum cam gear set is a perfect replacement and lasts forever (almost).
The one issue: You have to remove the cam since the gear is pressed on. If you are not strong in the mechanical arena, this is a pretty heavy duty job.
You have to remove the lifter cover, lifters, rocker arms, pushrods, front timing cover and accessories, distributor, oil pump drive (2 bolt oval plate at the RF of the lower engine block), then pull the cam. There are 2 bolts (10 mm) holding the cam retainer plate. They are accessed through the timing gear (2 holes).

You also have to replace the crank gear at the same time. The gears come as a set. They tend to 'wear' into each other, so replace both.
I suggest starting by removing the front timing cover (not too hard) and confirming the gear is whipped. You can leave most of the accessories on , pull the water pump and move the brackets out of the way. At least you'll know what you're up against.

After the cam is out, unless you have a hydraulic press... take the cam and aluminum gear to a machine shop and have them R+R'd. There is a cam retainer plate that is sort of fragile - as in easy to break... hopefully the shop won't break it.
Post your results...

One last note - as was mentioned earlier, if you jack up the right front and remove the tire, the distributor is right there.
You can remove it, I guess it will have to come out anyway.
 
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