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> problems with car, idles fine...pops when accelerated
DrifterJay
post Nov 20 2004, 12:52 PM
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ok...got car running...its idles fine....but when under acceleration, it pops through the carb like the exhaust is coming through the intake. Its not a typical carb pop. Any ideas suggestions?
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SirAndy
post Nov 20 2004, 12:57 PM
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QUOTE
Any ideas suggestions?


too lean ...
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DrifterJay
post Nov 20 2004, 01:09 PM
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its not lean...you could smell it if it was
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DrifterJay
post Nov 20 2004, 01:12 PM
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could an intake valve be too tight...making it fire inside the carb?
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SirAndy
post Nov 20 2004, 02:10 PM
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QUOTE(DrifterJay @ Nov 20 2004, 12:09 PM)
its not lean...you could smell it if it was

could an intake valve be too tight...making it fire inside the carb?

when was the last time you adjusted the valves ???

as for the smell, i always thought you could smell too rich instead ...
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DrifterJay
post Nov 20 2004, 02:28 PM
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couple of hours before putting the motor in....I even ran the motor before it was in the car to check the valves...
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SirAndy
post Nov 20 2004, 03:59 PM
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QUOTE(DrifterJay @ Nov 20 2004, 01:28 PM)
couple of hours before putting the motor in....I even ran the motor before it was in the car to check the valves...

well then, i stick with my initial thought:

too lean!

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redshift
post Nov 20 2004, 04:01 PM
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Overadvanced and too lean.

Misadjusted valves may add to that.


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Aaron Cox
post Nov 20 2004, 04:01 PM
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intakes arent too tight?
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DrifterJay
post Nov 20 2004, 04:23 PM
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ok
figured out the problem...sort of....all the valves are good spacing wise....the popping from number two is because the exhaust valve on that cylinder is not opening or closing fully...not even 25 percent....what are your thoughts? Bent pushrod? The valve is adjusted right. I am betting on a bent pushrod...if so....I will drop the engine down a few inches...pull the rockers and check the pushrod......Any advice though from anybody?....Did a compression check also...they are all 112-107...have spark on all cylinders...and fuel in every cylinder...Gap is good in distributor as is the timing....So I am certain on the pushrod being jacked up...
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DrifterJay
post Nov 20 2004, 04:29 PM
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bump
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Aaron Cox
post Nov 20 2004, 04:29 PM
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bad cam/lifter????
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DrifterJay
post Nov 20 2004, 04:37 PM
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hmmm maybe...
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Aaron Cox
post Nov 20 2004, 04:37 PM
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that would suck


i may be able to come over...im bored
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DrifterJay
post Nov 20 2004, 06:43 PM
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bump....changed the pushrod...(which was indeed slightly bent)....but the valve still does not do a full motion like the other exhaust valves....? any ideas suggestions...??? (IMG:style_emoticons/default/sad.gif)
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Dave_Darling
post Nov 20 2004, 06:57 PM
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Is the valve tip even with the other valve tips when the valve is closed?

Hrm, wait--you said even compression so it's unlikely to be a dropped seat.

OK, pull the lifter itself out and inspect it. It's unlikely to be the cam if it's only one cylinder (cam lobes are shared by the two opposite cylinders), but maybe a lifter.

Is the rocker arm correct? Did you torque the rocker shaft nuts correctly? (That cylinder at TDC, 10 lb-ft of torque.)

Can't think of anything else offhand.

--DD
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Cap'n Krusty
post Nov 20 2004, 07:04 PM
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If the adjustment is correct, the motion should be correct. A bad lifter or a bent pushrod would be compensated for by the adjuster, and a flat cam would, too. A flat cam would appear bad on both sides of the engine. Might be a bad guide, seizing the valve at times. The Cap'n
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Aaron Cox
post Nov 20 2004, 07:18 PM
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well - its bad on both sides for this one lobe. (IMG:style_emoticons/default/sad.gif) so..now what????
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redshift
post Nov 20 2004, 07:27 PM
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SirAndy
post Nov 20 2004, 07:28 PM
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QUOTE(Aaron Cox @ Nov 20 2004, 06:18 PM)
well - its bad on both sides for this one lobe. (IMG:style_emoticons/default/sad.gif) so..now what????

new cam ...

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