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frankenstein firing order

01-15-2010, 05:08 AM
i have a 1987 chevrolet blazer s-10, but the motor in it came from somewhere else. ive been told that it is a motor from an 1986 AMC jeep cherokee.( i replaced the oil pan gasket and that seemed to line up. thats when i found out that its not the stock motor. chevy uses a rubber gasket and the AMC jeep uses a cork gasket.) after replacing the transmission, i tried to hook up the spark plugs according to the haynes manual, but that doesnt seem to be the right order. according to google, the firing order for the jeep is the same. is it possibly a different motor? or is there another way of determining the cylinder position and firing order?

01-15-2010, 10:16 AM
Look on the intake for the stamped number. Did you pull the distributor or install a new timing chain?

01-15-2010, 01:50 PM
The AMC 2.8 V6 was supplied by GM to AMC as a complete assembly, including carburetor, water pump, alternator, PS pump and ignition system.
It is identical to the S-10 motor in every way, including the oil pan. If the pan gasket is not what you expect, possibly someone has changed it in the past.

The firing order is on the intake as noted above. But the #1 cylinder is the first one on the passenger side, which is different from most other domestic V-type engines.

01-16-2010, 12:59 AM
i did not remove the distributor or timing chain at any time. the number on the intake is 14089802. exhaust says k113. the valve covers say 14089275 and 14089276. behind the water pump on the block is a number as well A050429TBH. i looked under the distributor for a block casting number ( i was told its a 3 digit number) but i couldn't locate any number. the cylinders are marked on the intake as 1-3-5 front to back passenger side and 2-4-6 front to back driver side. i couldnt find the firing order on the intake though.

01-16-2010, 05:57 AM
The numbers you typed in is the firing order.
1-3-5 passenger side
2-4-6 drivers side
Look at your manual at the distributor picture. Find the number 1 spot and as you go around the wires will go to the cylinder referenced on the intake. Make sure you use the picture that the cylinders are referenced is the same.

01-16-2010, 08:16 AM
I think your problem is you are subconsciously going to No.2 instaed of No.1
When I quit working full time on cars I had a problem as Ford and Chevrolet were opposite sides for No.1 cylinder. I started looking at the number on the intake when hooking up my oscilloscope or a timing light.

02-09-2010, 06:01 PM
the firing order is 1-6-5-4-3-2 clockwise. Not sure about #1 position other than it should be one of the 2 posts at the front of dist. A lot of the dist. caps are marked at the #1 position with the number 1. The dist. may have been removed and then installed in the wrong position. To find out, remove the #1 spark plug, while placing your thumb on the spark plug hole, have someone bump the starter over until you feel air pressure at the plug hole. Look at the timeing marks on the harmonic balancer, it should be coming up on top dead center. With a socket and ratchet on the center bolt in the crankshaft pulley turn the engine untill it is at TDC. The rotor should be on # 1. If it is pointing anywhere other than one of the two front positions you can still make it run by making that position # 1. Just put the # 1 wire at the post that the rotor is aligned with and the rest of the wires from there. If you've never pulled a distributor don't try it, take it to someone who has. Make sure you remove the coil wire before you bump the engine over, so it wont crank.

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