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Discussion Starter #1
Here is what happens, turns over spins well but wont catch.

I have checked the spark at all 8 cylinders and I get a good blue spark. I have fuel pressure at the fuel rail and I can hear the fuel pump running.

I have also started a compression test and on cyl 1 and 2 it was right at 130 then on 5 it went down to 110 and 6 was at 100. NOTE: the starter is hot and it has been trying to turn the engine over alot in the past two hours. Now it is turning real slow. Could this cause a drop in the compression?

What are other things I should check? :banghead
 

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aka: kemicalburns
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do you have the correct firing order it will be different then the 302's. also make sure you put the dizzy in correctly. let the start cool down for a bit as well. whats the fuel pressure at the rail? should be 38lbs
 

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Discussion Starter #3
Checked the fuel pressure at the front of the rail and while starting it is 42psi.

also just verified the firing order and assuming counterclockwise rotation it is 1-3-7-2-6-5-4-8.

And after waiting about 30-45 minutes to try again cylinder 7 is also 130psi. So I will continue testing cylinders as the starter permits.

So now what?
 

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If you have spark and fuel, then sounds like timing is off. I would take dizzy out and get #1 at TDC(on compression) and reinstall dizzy just to make sure. You could be off a tooth. While you are trying to start motor, are you moving the dizzy around alittle bit to try and get it started? You just want to move it 1/16th of inch or so just to get the timing close enough to let the motor catch.
 

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Who needs oil anyways....
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edonward said:
I have also started a compression test and on cyl 1 and 2 it was right at 130 then on 5 it went down to 110 and 6 was at 100. NOTE: the starter is hot and it has been trying to turn the engine over alot in the past two hours. Now it is turning real slow. Could this cause a drop in the compression?
Only do your compression test with all plugs out and a fresh battery. If you've been trying to crank it for two hours now get the battery charged and start the test all over.
 

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Discussion Starter #6
Did the compression test with the plugs out and got 124 - 132 on all cylinders cylinder 5 being the weakest and one being the strongest.

I have tried changing the timing while starting and nothing. I do notice that turning the dist there is a point where a relay? or something engages. Not sure what that is.

:shrug I am lost!
 

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Who needs oil anyways....
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edonward said:
Did the compression test with the plugs out and got 124 - 132 on all cylinders cylinder 5 being the weakest and one being the strongest.

I have tried changing the timing while starting and nothing. I do notice that turning the dist there is a point where a relay? or something engages. Not sure what that is.

:shrug I am lost!
Put the timing back at 10*. But first put the #1 cylinder at TDC and make sure the pointer actually points to 0*. Mine got bent while I was changing my engine. Then put the engine at 10* on the compressions stroke and set the dizzy to 1. Have you pulled codes to make sure you get a 11-11 ok code? Did you check the amount of pressure at the rail or just put something in the schrader valve to see if there was any pressure?

There should be no type of "relay clicking" when turning the dizzy.

Also, are you sure the cam and crank were in the correct positions when putting on the timing chain?
 

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Ex Navy Nuke
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Put a timing light on it while someone else cranks it over so you know what your timing actually is. You can adjust it while they crank it. This will take out the guess work on the timing issue.
 

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RLKBOB said:
Put a timing light on it while someone else cranks it over so you know what your timing actually is. You can adjust it while they crank it. This will take out the guess work on the timing issue.
That poor battery. :toothless
 

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Discussion Starter #11
Ok... I got a couple of cylinders to fire after using a timing light and getting it set to 10* but the battery is dead and it will not start the truck I will let it recharge and report back in a bit.

Thanks to everyone for their suggestions, at least I have hope again.
 

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k1w1t1m said:
Just a thought...are the injectors working?
Good question. If you can get an injector harness at the yard, you can hook one up to a 12V source and use a momentary switch to trigger it and listen if it opens.
 

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Discussion Starter #14
I have an extra wiring harness. What would it take to do this?

I am using the injectors that were in the 302 and they were working when the 302 came out.
 

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edonward said:
I have an extra wiring harness. What would it take to do this?

I am using the injectors that were in the 302 and they were working when the 302 came out.
Hook the ground of the injector to the negative of a battery, hook the positive to a momentary switch (one that requires you to hold in the on position or it snaps back to off) and the other end of the switch to the positive of a battery. You should hear it click open when you briefly flip the switch. I did it when cleaning mine. Pretty sure you hear it click. However, if they all worked in the 302, I would suspect something in the 351 harness first. Give it a try again after the battery is charged. If you are sure certain cylinders are not firing, swap the injectors around and see if it stays those cylinders or follows the injectors.
 

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Discussion Starter #16
OK, I got it started, it was the timing.

:brownbag Put in to much tranny fluid. I know everyhting says not to put to much, but what happens if you do? I don't have a drain plug. :shrug

Should I pump/drain some of the fluid out?
 
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