Author Topic: 81 scottsdale 305 auto installed oil pressure gauge where did i go wrong?  (Read 238 times)

Offline Walnut777

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I was installing gauges in my 81 c10 305. I removed the distributor cap marked the position. removed the distributor so i would have some room to install the fitting for the oil pressure gauge. Installed it the truck crunk up but it is misfiring. Now it wont start at all and blows sparks out of the carb. The distributor was put back in just like i took it out. The wires are in the right order. the wiring harnesses are plugged back into the distributor. I KNOW I read something somewhere about issues cranking when the 2 wire harness from the oil pressure switch was unplugged. maybe im wrong. It seems like I read when that harness is unhooked is causes some issue with the wire going to the electronic choke. I looked at a wiring diagram and i believe the truck has the electronic spark control module.
« Last Edit: April 16, 2019, 09:04:31 PM by Walnut777 »

Offline Irish_Alley

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what did you mark? its important to mark were the rotor is and install it back to where it was found.
If you canít tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline Walnut777

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i marked the distributor shaft and the block and rotor button.

Offline zieg85

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More than likely you are 1 tooth off.  When you remove the distributor the gear rotates as you pull it up which rotates the oil pump rod.  If you dropped it back it with no problems it is a tooth off... Been there done that.
1985 C30 Custom Deluxe Ext. cab 5.7L TH400 3.21 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline Walnut777

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I think I found the problem. I had a firing order diagram for my truck but I think it was wrong. it was showing plug wire 1 and 8 on the back of the distributor closest to the firewall. I checked on this forum and it shows 1 and 8 on the front of the distributor. when I get home. ill switch it around.

Offline JohnnyPopper

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Always Take Pictures!!  ::)

Offline Captain Swampy

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Bring the #1 cylinder to TDC on the compression stroke. Usually the rotor is pointing towards the front passenger side. 18436572
1987  350TBI 700R4  4X4  4.56 gears  33" BFG All Terrain


http://forum.73-87chevytrucks.com/smforum/index.php?topic=32209.0

Offline Walnut777

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Sorry so late with an update.
I had lost my paper showing where the wires go on the distributor.
I googled it and autozone was showing 8 and 1 in the front and it was under 81 c10.
After I sat back awhile. I thought that wasnt right. 8 and 1 were in the rear.
Found the correct firing order and fired right up.

Autozone had a Pontiac 305 listed from.what I could find searching.
Contacted them and the link was fixed.