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Discussion Starter #1
How would I tell if the cam was gone after initial start up?

Could only keep it running for about 30 seconds by goosing the throttel repeatedly. Developed a shudder when the revs went to 3k or so. Didn't feel right to me but before I throw up after dumping the time and money into my first build I thought I'd do some checking based on what you all have to suggest.

Thanks
 

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You CANNOT wipe out your cam in the first 30 seconds of starting...

Describe how the 20 minute break in went. Or have you gotten that far yet?

You might only have a wire crossed.

FE
 

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Discussion Starter #4
Thanks guys,

69 302 f-100.
.30 over
comp xe256-10
guide plates, screw in studs, HD pushrods, adj roller rockers, matched lifters, springs.
summit intake, autolite 4bbl (manual choke) the rest is std.

Didn't make the 20 min. just 30 seconds running-she didn't want to stay alive without mashing the throttle.

Motor on stand 2 weeks while I finished pumps , pans, intake etc.
Once installed filled up all fluids (rotella t per comp cams bulletin) primed til it ran out the pushrods (50lbs). About 45 minutes later attempted to start (had valve covers on) missed the coil wire and cranked it 3 times for a couple seconds each time before I hooked up the lead. Next attempt fired but died immediately, couple of xcel pump shots tried again and it fired and wanted to die but I kept mashing the pedal to keep it alive. Plugs gapped, dwell set, #1 TDC (both valves closed, piston at top of cylinder) and dizzy set accordingly, plug wires routed per chiltons.

That's about it. As a first timer I greatly appreciate any suggestions.
 

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doesnt sound like a cam lobe problem. check your wires / electrical. if you havent broken the cam in yet dont rev over 3k. do your cam break in then see that happens. do you have a problem under 3k?
 

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I think you either crossed some plug wires, or have the wrong firing order, or maybe you have a huge vacuum leak.

You set the dwell on the points... Open the point gap to about 35 for the run in, break in needs a running engine.

Then check for that vacuum leak again.

Set the initial timing around 12* to be safe right at first...
 

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Discussion Starter #7
After popping the valve covers and not finding anything, I pulled the dizzy cap then brought #1 to the top of it's bore with both valves closed (TDC right?) and it jived with the balancer reading...but the rotor was pointing opposite #1.

Hate to sound like a newbie (wait a sec.. I am) but does that mean I just need to pull the dizzy, swivel the rotor 180 and put it back? Could have sworn I put it in right...

Would it run for even 30 sec. that far off?

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at 180 off i think it is all shudder and flames out of the carb....at least that is from experience...um i mean, i've never done that before.:
 

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Yeah... Ummmmm I heard that somewhere too... BUt I do believe that there is a particular firing order of a 302 that will run half assed being 180 out but needs lots of air....
That's all speculation and rumor though... Not that I've ever done that either.......
 

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its amazing how off you can be and still have our fords run... MANY times I've removed a whole bank of plug wires while removing a valvecover and then forgot to hook them back up..... and they frequently would start up with only 4 plugs working.. ran like crap but I'd still be scratching my head why it was running so rough (a little slow on the uptake I guess)
 

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Discussion Starter #14
Not that I'm trying to show HOW slow I am but...I was checking it today and with the balancer showing TDC and the rotor at 6, both #1 and #6 looked like they were at the top of their bores when I pulled the plugs, and both sets of rockers appeared to be closed.
Not looking for a discussion on motor theory but will it do any good re-stabbing the dizzy if I can't tell which one really TDC...I look forward to any suggestions after you've stopped laughing...

Thanks for humoring me
 

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#1 and #6 pistons work in the same direction. When #1 is on TDC compression stroke, #6 will be on TDC exhaust stroke and sometimes if you aren't paying attention, you can find yourself thinking that both are at TDC compression stroke at the same time. One is on overlap, the other is not. Hard to explain. I believe on most 90 deg. V8's that there are always 4 cylinders working in the same direction as the other 4. On Fords, it's 1&6, 5&3, 4&7, 2&8...going off of memory. It's always the same cylinders reguardless of make, but other mfg's number their cylinders differently.

Anyway, if you pulled the cap and the rotor was 180 deg. off, chances are that #1 cylinder was on TDC overlap instead of TDC compression. Just turn the crankshaft a full turn and the rotor would line up correctly on the right stroke.

The way you describe what was happening when it was running, it sounds like a vacuum leak and/or severely retarded timing. Might be wrong, but that's what it sounds like...and both are easily fixed.

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"it is better to appear ignorant than to open your mouth and remove all doubt"--Mark Twain

<font size=-1>[ This Message was edited by: mavman on 1/8/07 8:04am ]</font>

<font size=-1>[ This Message was edited by: mavman on 1/8/07 8:05am ]</font>
 

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Don't be deceived when it "looks" like both valves are closed at TDC. It will look that way on either stroke. You need to find TDC after the intake valve has gone through it's full stroke.
 

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That's the way it looks because they are Both at tdc...

Find out from the manufacturer what the firing order is supposed to be according to the cam you bought.... 302's had 2 diffrent firing orders and you may have it off.


FE
 

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That's the early.
 
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