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Old 07-07-2015, 08:02 PM   #1
Mr.Hyde
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Firing up..

So I'm having an issue trying to start up my truck the first time I have the firing order done correctly checked 3 times 1 one piston is at top dead center and I have the rotor pointing at cylinder one reference marks. I get a blip of running then after 2 second it stops doesn't want to die I don't want to continue until this is taken car of due to it being a fresh rebuild can you guys help me out? I popped off the valve cover and 3,5,7 look to be the valves are closed in the compression stroke and both cylinder 1 rockers have play in going to do some reading tonight. It's a bit difficult seeing I am doing this pretty well alone.
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Old 07-07-2015, 08:15 PM   #2
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Re: Firing up..

You're off 180 degrees and trying to start on #6.
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Old 07-07-2015, 08:55 PM   #3
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Re: Firing up..

concur. #1 comes to TDC twice during a 4-stroke process, compression and exhaust. #1 should be on compression stroke when setting the timing (i.e. around TDC and rotor pointing at the #1 cylinder spark plug tower - just before ignition with both valves closed). If both valves for #1 cyl are not closed (like you mention 3,5,7 are) then it's not on the compression stroke. Sounds like you may be on the exhaust stroke. Was the dot on cam timing gear at the bottommost point and the dot on the crank timing gear at the uppermost point - i.e. aligned to each other vertically - during assembly?

Personally, before tearing things apart, recommend reset TDC on #1. If it looks like the valves are closed, then set your timing and try to start it. If you reset TDC on #1 and it looks like you describe now, rotate another full rotation of the crank (this is only a 1/2 rotation of the cam gear for SA) and bring #1 back to TDC again - and confirm both #1 valves are closed - then set timing and try to start it.

Last edited by jocko; 07-07-2015 at 09:02 PM.
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Old 07-08-2015, 12:19 AM   #4
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Re: Firing up..

Not sure on the assembly portion I had my engine rebuilt by a local shop, I assume so he was recommended to me and seemed knowledgeable also doing it for 30 years. I was thinking that's why I would get a blip is from residual fuel in the cylinder causing it to fire off a little bit.

So when the piston is on tdc compression stroke what should I be looking for exactly for when both valves are closed will I have any play or will it be tight to even wiggle it.
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Old 07-08-2015, 12:33 AM   #5
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Re: Firing up..

Instead of figuring out where the valves are, just pop the cap off, bump it around so the rotor points at #1, loosen and lift the dizzy, rotate the rotor around to point at #6, lock it down, put cap on and fire it up.

Or retime it.
Pull #1 plug, stick your thumb in the hole, bump it over till you feel compression, line up the timing tab at zero. Point the rotor at #1, rotate dizzy 1/2 inch ccw, lockit down and fire it up.
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Old 07-08-2015, 07:00 AM   #6
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Re: Firing up..

Quote:
Originally Posted by Mr.Hyde View Post
Not sure on the assembly portion I had my engine rebuilt by a local shop, I assume so he was recommended to me and seemed knowledgeable also doing it for 30 years. I was thinking that's why I would get a blip is from residual fuel in the cylinder causing it to fire off a little bit.

So when the piston is on tdc compression stroke what should I be looking for exactly for when both valves are closed will I have any play or will it be tight to even wiggle it.
Yes when on TDC on number 1 cyl both valves will be closed so the rockers will be in the same position. the lifters are key to your question, solid or hydraulic? if solid you should have a little play, if hydraulic there is a spring inside so it will be under some tension but not as much as if a valve is open.

I usually pull the plugs before rotating the engine if it won't turn over easy with a breaker bar and socket, assuming the valve cover is off then rotate the crank and watch the valves move, intake opens then closes just before the compression stroke, power stroke then the exhaust opens, then there is an overlap where the intake is opening while the exhaust is closing.

i also use a remove start button and stick my thumb into the spark plug hole to feel the compression, once you feel the compression start to build then continue turning the crank until the 0 degree mark lines up with the damper mark.
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Old 07-08-2015, 07:28 AM   #7
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Re: Firing up..

I'll see what I can do about getting a pair of hands so I can bump the starter and find the compression stroke then I guess once I feel the air push my thumb off turn it back to 0
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Old 07-08-2015, 08:20 AM   #8
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Re: Firing up..

Or make a whistle out of an old sparkplug. Knock the porcelain off and drill an 1/8 inch hole down the middle. No need for another hand.
Or do the simplist thing. Move the rotor onto #6.
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Old 07-08-2015, 08:37 AM   #9
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Re: Firing up..

X2 on being 180 out. Your timing chain gear marks need to be at 12 o'clock and 12 o'clock not 6 o'clock and 12 o'clock. Spin the distributor 180 or just put the #1 plug on the #6 point and run your firing order from there.
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Old 07-08-2015, 09:06 AM   #10
Mr.Hyde
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Re: Firing up..

I'll try rotating the rotar 180° I assume I don't need to change the location of any spark plug wires.
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Old 07-08-2015, 09:09 AM   #11
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Re: Firing up..

Quote:
Originally Posted by Mr.Hyde View Post
I'll try rotating the rotar 180° I assume I don't need to change the location of any spark plug wires.
That is correct!!
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Old 07-08-2015, 09:10 AM   #12
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Re: Firing up..

Thanks I will keep you guys posted with what happens depending if it fire you might get a video of her running!
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