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Author Topic: Timing  (Read 7485 times)

Offline greenmonster

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Timing
« on: January 11, 2008, 10:00:26 pm »
My truck runs fine but one day I put a timing light on it and noticed it had alot of advance.I turned the distributer and it started to back firer though the carb before I could even get it on the timing marks.I thought the timing marks were off but I checked and TDC is right on zero.It has a rv cam in it do you think the cam is off.If so should I fix it.
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Offline Fordeatinz71

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Re: Timing
« Reply #1 on: January 11, 2008, 10:04:35 pm »
are you positive you aren't one tooth off?  yea, your TDC might be "on", but it doesn't mean you have the distributor lined up just right.  one tooth can happen to the best of us.  and yea, if your cam is off...i'd say you'd need to fix it. 
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Offline greenmonster

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Re: Timing
« Reply #2 on: January 11, 2008, 10:48:15 pm »
How do I check the distributor.
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Offline VileZambonie

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Re: Timing
« Reply #3 on: January 12, 2008, 12:53:27 am »
You can put the distributor in anyway you want provided you have enough room to rotate it to acheive your proper timing. What you should do is (assuming you have an HEI w/ vac advance) check your timing with everything hooked up at 2500 RPM and see what it is.
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Offline greenmonster

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Re: Timing
« Reply #4 on: January 12, 2008, 06:08:16 pm »
I don't have a light with advance to do that.But like I said it run fine.I am confused on why the timing marks are off but TDC is right on.
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Offline VileZambonie

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Re: Timing
« Reply #5 on: January 12, 2008, 06:58:33 pm »
 ??? If when you are at TDC the timing pointer zero mark lines up with the balancer mark then your marks are fine. Not realy sure what the problem is here
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Offline greenmonster

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Re: Timing
« Reply #6 on: January 12, 2008, 07:41:32 pm »
Yes the marks are right on.I was thinking the cam was off a tooth.Is it possible for it to run fine if the cam is off.If i bring the timming to 12 degrees it idles but if I give it a little gas it back fires though the carb.
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Offline VileZambonie

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Re: Timing
« Reply #7 on: January 12, 2008, 07:44:50 pm »
I doubt you jumped timing on your chain. It'd have to be REALLY sloppy and would be making a lot of noise. Which way are you turning the distributor to make it pop? Counter clockwise or clockwise? Do you have an HEI with vacuum advance?
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Offline greenmonster

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Re: Timing
« Reply #8 on: January 12, 2008, 07:56:41 pm »
It is HEI with vac.I dont think it jumped time I was thinking the guy I bought the truck from put the cam in wrong.I think I was turning it counter clockwise.
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Offline VileZambonie

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Re: Timing
« Reply #9 on: January 12, 2008, 08:02:51 pm »
Counter clockwise is advancing it. If you are advancing it and only getting 12° advance with it popping I'm gonna suggest you don't have the inductive clamp around the #1 spark plug wire or you have more issues.
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Offline greenmonster

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Re: Timing
« Reply #10 on: January 12, 2008, 08:10:42 pm »
I dont remeber witch way I turned it but I do know when I look down at the timing marks the one on the balancer is to the left of the marks about two inches.If I turn it to get the mark on time it will back firerwhen I give it throttle.
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Offline VileZambonie

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Re: Timing
« Reply #11 on: January 12, 2008, 08:43:13 pm »
Well we really need to know if you are advancing it or retarding it. Counter clockwise would be advancing it. Clockwise would be retarding it. You should invest in a decent timing light. Most now have advance, RPM and a metal inductive clamp that won't melt for under a hundred bucks.
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Offline greenmonster

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Re: Timing
« Reply #12 on: January 12, 2008, 08:48:09 pm »
I am retarding it to get it on time it is showing that it is way advanced.
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Offline VileZambonie

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Re: Timing
« Reply #13 on: January 12, 2008, 08:50:02 pm »
What RPM are checking your base timing at? Are you disconnecting the vacuum advance and plugging it when you check it?
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Offline greenmonster

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Re: Timing
« Reply #14 on: January 12, 2008, 08:56:00 pm »
At idle around 800 rpm and with vac disconected.If I plug it in to full vac the mark gets farther away.
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