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Old 09-23-2007, 01:51 PM
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Default me 1 car 0

Well fellers ..

I went back through all the notes and PM's (very thankful for the help) yall sent me and started from scratch this morning ...

confirmed tdc
confirmed orientational of rotor

and started her up ... with only headers its pretty noisy...
she still backfires a bit ... pops like popcorn but kept spinning
tried to give it a very little bit of gas when under the hood ... got a little bit of flames..so I stopped doing that ...

tried a few times to turn the distro to see if it would help but didnt seem like it did all that much. i mean I noticed a slight difference when I did it but I can't seem to get her to settle down and just purrrrrrr or whomp whomp whomp, etc.

I have a power on switch which brings power after the master arm is turned on . In my way of building it I was thinking/hoping that turning it off with the master on would kill the motor but thats not the case .. so I need to rethink that one.

anyways I will take today as a success and thank all of you for your help.

here's to you guys
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Old 09-23-2007, 02:10 PM
Dawson Motorsports
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Here are some things to check:
Timing, Valve adjustment, Firing order, all of these could create your poping back.
The #5 and #7 spark plugs come one after another, easy to get them mixed up.
Keep plugging away,
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Old 09-23-2007, 02:54 PM
jimwheeler jimwheeler is offline
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Join Date: Oct 2004
Location: Kansas City
Posts: 5,251

Like Chuck said. Sounds like firing order to me.
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Old 09-23-2007, 03:37 PM
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Sounds like tight valves to me, assuming from the other thread you are hyperaware of firing order, etc. Big lazy flames from carb, or a hot little crisp backfire? (That's the one I would describe as popcorn) I would wholesale back off your valve adjustment one turn and try again. If that is it then warm it up pretty far and do a hot valve adjustment. Do you have the little saying? I always have to get it, so I write it under the hood.

To properly have the Master Switch kill the car, you need to have the 4 terminal one, with the alternator output going thru the switch's minor terminals, or the ignition circuit, or on FI cars the injector power, or fuel pump power. Depends on location of the switch and ignition power is probably best.

When you turn off the conventional style of master switch on a running car, it is just like disconnecting the battery, so the energized alternator keeps the car running. However, this is hard on the alternator, the internal voltage goes very high with the current having no place to go, and it can toast the regulator or the diode trio, esp at high RPMs.

Isn't car building fun?!

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Old 09-23-2007, 03:46 PM
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uggg .... valve stuff ... guess what.. more new stuff..

Kyle ..

the master switch kills all the juice just fine. Its a two pole master.. What I was hoping to achieve was

1. master switch on ,,,
2. at the dash .. power switch on (give juice to the ignition, fuel pump, front lights, wipers, light to the gg's
3. Ignition on

that works fine . just not in reverse. I want to be able to turn the power switch off at the dash and kill the motor at that point...

little saying .. "never take a wooden nickle".... "measure twice cut once"??

should anyone have any pointers on proper valve lash pass it on please .. I have the feeler tool just not sure of any nuances or how to's

thanks again guys....
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Old 09-23-2007, 04:04 PM
Mark Allen Mark Allen is offline
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Join Date: Nov 2004
Location: Washington, MI
Posts: 643


To properly check the valve lash you first need to check the specs. Since I think you have a Jerry Post motor, ask him what the valve lash should be. Somewhere between .016" and .025" on the intake and between .018" and .030" on the exhaust depending on the cam grind.

Set the engine at TDC #1 firing and take off the valve covers. The rockers on #1 (both rockers) should be loose a bit and if you grab them and wiggle them side to side there should be free play. Back off the nut a bit and put your feeler gauge in set to the right gap. Slowly crank down the adjuster nut until the gauges just drag in and out, then set the lock nut. Do this for both valves and then crank the engine 90 deg clockwise (viewed from the front). Repeat the lash for the next cylinder (#8), then turn 90 deg again and work your way through the firing order. 1-8-4-3-6-5-7-2

Then double check your distributor cap. Starting with #1 plug wire and going clockwise around the circle insure again that it goes 1-8-4-3-6-5-7-2.

Kyle is absolutely correct, you need a 4 pole master switch with the alternator circuit going through the minor poles (it's on the diagram I sent you). The safety crews need to be able to kill your car with one flip of the master switch in an emergency so this is a must.

You're close, good luck

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Old 09-23-2007, 04:07 PM
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Master works fine when motor is not running, but when motor is running the alternator is now a power source too. So shutting off the master just isolates the first power source (the battery) and the spinning alternator is supplying power.

You have to get a 4 pole Master switch to immediatly kill any car with a modern alternator quickly. Just think of it as two switches tied together that break when you spin the handle.

So simply take the wire that powers your coil back to the "Minor" terminal on the Master, then out of the other minor terminal to your coil. This way, if a corner worker turns the power off, the big starter cable is isolated from the battery, and the coil is powered down immediately killing the motor.

And the valve adjustment thing is a touchy task. Go read the entire tech article about it at the Crane Cams web site. If things are too astray there you may end up hurting stuff on break in.

The phrase is, Adjust the intake as the exhaust starts to open, and adjust the exhaust as the intake is almost closed... Knowing this you can just run down one side of the motor at a time, independant of firing order or cam grind.

But don't mess with that first, back every valve off 1 turn and diagnose your problem. If that helps then great, if that doesn't then there are more things to check.
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Old 09-23-2007, 06:53 PM
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jkopp jkopp is offline
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Location: Wellsville, KS
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Not to be picky Jorge but shouldn't it be "me 1 car 1"?
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Old 09-23-2007, 07:54 PM
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Originally Posted by jkopp
Not to be picky Jorge but shouldn't it be "me 1 car 1"?
X2. And instead of "Thank You Workers" he needs to put a "Thank You ASedan.net"!

Keep at it, I remember when I fired my engine for the first time....you'll get there.
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Old 09-23-2007, 08:37 PM
Tim White Tim White is offline
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Join Date: Nov 2004
Posts: 357

I only have a two pole master switch, I just have the battery and the power to the alternator on the same pole.
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