CRG Discussion Forum

Camaro Research Group Discussion => Mild Modifications => Topic started by: greg1ontheedge on May 30, 2006, 05:03:14 PM

Title: 350 Won't Start???
Post by: greg1ontheedge on May 30, 2006, 05:03:14 PM
Either I'm losin my mind or gettin old. Put a new intake manifold and carbs on my 350, now it backfires through the carbs and the exhaust (not at the same time???). I timed to 8 BTDC as before the changes (nice cam), double checked firing order 18436572, number 1 being front of engine, driver's side. What the heck am I missing???  Thanks...............
Title: Re: 350 Won't Start???
Post by: My68SS on May 30, 2006, 05:27:16 PM
Backfiring like that can only be ignition timing. Rotate the motor til the tdc line on the balancer is on the mark. Remove the dizzy cap and check that the rotor is facing either No 1 or No 6 plug lead and the points are open.
If that's ok then you may have the dizzy 180 deg out i.e firing on No 1 when it should be firing on No 6. or vise versa.
Title: Re: 350 Won't Start???
Post by: greg1ontheedge on May 30, 2006, 05:54:48 PM
Thanks man.  I'll check everything, again.  Appreciate your response, can only be timing....  I just don't understand what I'm missing, should be simple, done this a hundred times..........
Title: Re: 350 Won't Start???
Post by: Buddy on May 31, 2006, 03:24:11 PM
I'll bet on the dist being 180 out.

Title: Re: 350 Won't Start???
Post by: greg1ontheedge on May 31, 2006, 08:17:46 PM
So, thanks everybody.  DUMB!!! question.  Can I just move the spark plug wires 180 or is there some reason I actually need to pull the dist out and rotate 180???  I know, I know.  Thanks again............
Title: Re: 350 Won't Start???
Post by: Buddy on June 01, 2006, 01:33:20 PM
Rotate the distributor, you only have to lift it up about an inch or so. You would only  be creating problems and confusion for the next person that works on it.

Title: Re: 350 Won't Start???
Post by: 67camarorsss on June 08, 2006, 09:59:40 PM
Try this with the distributor:
1 - Disconnect high tension lead (the middle wire in the cap).
2 - Remove #1 cylinder spark plug.
3 - Place finger over hole that spark plug was in.
4 - Turn the engine over, feeling for pressure in the spark plug hole.
5 - Stop motor when pressure develops. This will be close to #1 cylinder firing.
6 - Check balancer wheel mark. Turn engine over BY HAND (use a breaker bar) and align the mark with 8 deg BTDC.
7 - Remove the distributor cap. Now you can check the position of the rotor on the distributor.
8 - If it's pointing sort of close to the front of the car (actually closer to the #1 plug than straight ahead) then you're in the ball park.
9 - If it's pointing towards the firewall then you're 180 degrees out and will need to remove the distributor and realign.
10 - To realign the distributor:
       10A - Remove hold down and pull distributor from the block.
       10B - Look in the hole and insure that the oil pump drive shaft slot is pointing front to back. If not...
       10C - Align the shaft slot front to back using a long straight blade screwdriver.
       10D - Orient the distributor with the vacuum advance canister pointing towards the left front corner of the car.
       10E - Turn the rotor approximately 15 degrees CCW.
       10F - Drop the distributor into the block. The gear should engage the cam gear and the tang on the distributor should engage the oil pump driveshaft. It may take a few tries.

Now that you've got the distributor in correctly you should:
11 - Reattach distributor hold down.
12 - Put the cap back on.
13 - Reconnect and wires that were disconnected.
14 - Assemble timing light and any another devices that will be required to set timing (dwell tach, etc.).
15 - Turn the key to the "ON" position. DO NOT start car!
16 - Rotate the distributor back and/or forth untill the timing light blinks. Get it as close as possible.

Now, you can start the car after tightening down the hold down sufficiently to keep the distributor from rotating. Furhter adjust timing and dwell to specs. Note: This assumes that you have the points properly gapped and that you have the vacuum advance hose disconnected.
Title: Re: 350 Won't Start???
Post by: hotrod68 on June 14, 2006, 03:22:39 AM
The way I do it is get #1 up on the compression stroke, then turn the balancer to 0-degrees with the timing mark. Engage the distributor gear with the cam with the rotor pointing toward #1 cylinder, then wire the cap with the #1 plug wire in that terminal. Bump the engine over with the starter and the distributor will drop down and stay in time with the cam and engage the oil pump if it didn't drop down to begin with. This will put the points window on the cap in the correct position to the right for external adjustment, the vacuuum advance canister in the right position, and allow for timing adjustment once the engine is running. Works for me every time! Just my 2 cents.
Title: Re: 350 Won't Start???
Post by: dans67camaro on March 11, 2007, 02:46:15 PM
Don't know if you solved your problem, but another reason you could have those system is if your cam is shot. Happened to me on a later model 350 and it was the cam. Seems the lobes were worn..... heat treat issue I suspect!