it wont start
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Member
Joined: Dec 2002
Posts: 11
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From: Madison, AL
it wont start
Ok, here is the story. I bought a 1986 F150 4X2 with the 302 and C6 tranny. it is fuel injected. the guy I bought the truck from said that the truck got a new short block three years ago and he bought it one year ago. he says the truck was real powerfull when he got it and that he noticed it started to loose power, then the waterpump went bad and he blew the headgaskets. he got one of his "buds" to do the repair work and when he got the truck back it would not run. he replased the spark plugs, wires, cap, rotor, fuel filter, pump, and air cleaner. I buy it and can smell gas and every once and a while it will backfire through the throttle body. it also has spark. I reset the distrib to TDC, still dont run. checked compression on #1 and got 125 also checked #5 and got 125, so im lost I dont want to tear the motor apart to check the valve timing, please help
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Joined: Sep 1999
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From: Ventura, California
Valves may be out of adjustment. Check the compression on all 8 cylinders. If it's getting fuel and spark, than it's either a loss of compression (gasket, warpage, valves, etc), or it's not getting any air. Since I'm sure you've eliminated any possibility that would prevent it from getting air, it has to be compression related.
An internal combustion engine only requires air, fuel, spark, and compression to run, so just eliminate them one at a time until you find it. If you get good compression in all 8 cylinders, then you are mistaken about either the fuel or the spark, and you will have to check them more closely.
Take care,
~Chris
An internal combustion engine only requires air, fuel, spark, and compression to run, so just eliminate them one at a time until you find it. If you get good compression in all 8 cylinders, then you are mistaken about either the fuel or the spark, and you will have to check them more closely.
Take care,
~Chris
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Joined: Aug 2001
Posts: 33
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Better check to see if its wired right. It sounds like itsfiring when the intake valve is open.
You don't have to open the engine to see if its timed right. Remove the valve cover and expose the rockers for no. 1 piston.
Turn the crankshaft and observe the rockers
With no. 1 plug removed use a length of shot wire (I've even used the dipstick) and carefully find the top of the piston through the plug hole. If you find the piston up and the valves are closed, set your dist. rotor to no. 1 on the cap.
Check to see if your damper timing marks are at zero.
If it wants to "whuff" when you turn it over, you are 180 deg. out of time. Note where the tip of the rotor button is and pull the dist.,turn theshaft 180 deg (exactly opposite) and set the dist back in.
You don't have to open the engine to see if its timed right. Remove the valve cover and expose the rockers for no. 1 piston.
Turn the crankshaft and observe the rockers
With no. 1 plug removed use a length of shot wire (I've even used the dipstick) and carefully find the top of the piston through the plug hole. If you find the piston up and the valves are closed, set your dist. rotor to no. 1 on the cap.
Check to see if your damper timing marks are at zero.
If it wants to "whuff" when you turn it over, you are 180 deg. out of time. Note where the tip of the rotor button is and pull the dist.,turn theshaft 180 deg (exactly opposite) and set the dist back in.
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Joined: Dec 2002
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From: Madison, AL
update
ok guys, I pulled the cap and plugs just to check them and ended up replacing the cap cause of its condition. also the plugs were gapped to like .060 so I set them all to .043, also drained the oilpan, and guess what there was about 4 gallons of a oil/gas mix, very bad, so now it has new oil and filter and gapped plugs, as well as correctly gapped plugs, It still dont run. what am I missin.