HELP NEEDED!!!! 383 Wont start...
Thread Starter
Burning Brakes
Joined: Apr 2000
Posts: 959
Likes: 1
From: Lemoore CA
HELP NEEDED!!!! 383 Wont start...
Ok, so I finally got everything hooked well enough up to get the motor to turn over. We primed the motor by removing the spark plugs and cranking the motor over until we got oil pressure. I then reinstalled the spark plugs and tried to fire up the car..... However Ive come to find that the timing is way out of wack.... Either ignition timing...or cam timing :( Im so convinced its on my behalf with the ignition timing somehow.... the machine shop installed the cam and chain....... Very professional and good shop
So the car just spun the motor and the ignition would backfire into the intake plenum (Super Ram) We tried moving the distributor ahead another gear, same problem. Then tried it 180 degrees out same thing.... So we pulled the valve cover and checked for TDC retimed the distributor same problem.... I dont know what to do..... Its a Super Ram Hot cam 383 motor.... We're not using a light, and we havnt worried about fine tuning the distributors position.... My thought is either something in the car is very picky about ignition timing, the wires are in the wrong firing order or maybe something electrical that Im not thinking of.
I need help badly please I hope someones been through this.
Paul
So the car just spun the motor and the ignition would backfire into the intake plenum (Super Ram) We tried moving the distributor ahead another gear, same problem. Then tried it 180 degrees out same thing.... So we pulled the valve cover and checked for TDC retimed the distributor same problem.... I dont know what to do..... Its a Super Ram Hot cam 383 motor.... We're not using a light, and we havnt worried about fine tuning the distributors position.... My thought is either something in the car is very picky about ignition timing, the wires are in the wrong firing order or maybe something electrical that Im not thinking of.
I need help badly please I hope someones been through this.
Paul
Melting Slicks
Joined: Mar 1999
Posts: 3,029
Likes: 137
From: Nashville TN area
Re: HELP NEEDED!!!! 383 Wont start... (Nomar116)
i'd check plug wires for correct locations first..
sounds like you covered everything else..
only other thing i know that could cause backfire would be a valve not closing all the way.. had this problem when i had valve lash set too tight.. but then the motor didn't crank too easy either with the starter.. so it was obvious to me right away..
i have an LT1 so not sure how much more help i can be.. not familiar with L98 ignition/timing setup..
keep us posted..
sounds like you covered everything else..
only other thing i know that could cause backfire would be a valve not closing all the way.. had this problem when i had valve lash set too tight.. but then the motor didn't crank too easy either with the starter.. so it was obvious to me right away..
i have an LT1 so not sure how much more help i can be.. not familiar with L98 ignition/timing setup..
keep us posted..
Burning Brakes
Joined: Feb 2000
Posts: 958
Likes: 1
From: SF Bay area, CA USA
Re: HELP NEEDED!!!! 383 Wont start... (Nomar116)
Lets start with the firing order. Look at the direction the distributor rotates when you crank the engine over. Make sure the wires are lined up in the same direction 18436572 should be the firing order you need.
To get the timing close, crank the engine ove until it is TDC on compression stroke (remove the number 1 plug and put your finger over the hole while someone bumps the starter if the compression is building as the timimng mark approaches tdc you are on the comp. stroke if not crank arounf one more time. Next look to see if the rotor is pointing at the terminal that the number 1 wire is connected to. If not rotate the dist. or move the wires. Once it is close pull the wire off the number one plug and stick a screwdriver in the end or something else that you can use to see a spark shoot to ground. Then turn the ignition to "on" and move the distributor back and forth when you see the spark shot to ground you will have the timing at TDC and the car should be able to start.
To get the timing close, crank the engine ove until it is TDC on compression stroke (remove the number 1 plug and put your finger over the hole while someone bumps the starter if the compression is building as the timimng mark approaches tdc you are on the comp. stroke if not crank arounf one more time. Next look to see if the rotor is pointing at the terminal that the number 1 wire is connected to. If not rotate the dist. or move the wires. Once it is close pull the wire off the number one plug and stick a screwdriver in the end or something else that you can use to see a spark shoot to ground. Then turn the ignition to "on" and move the distributor back and forth when you see the spark shot to ground you will have the timing at TDC and the car should be able to start.
Thread Starter
Burning Brakes
Joined: Apr 2000
Posts: 959
Likes: 1
From: Lemoore CA
Re: HELP NEEDED!!!! 383 Wont start... (weekendwrench)
Ill give some more info.... I think my distributor is installed backwards. The ECM wire connection on the distributor ponits directly towards the rear of the car. The spark plugs were all set according to the manual 3/4 turn past lash. As for checking the ground, how do you get the spark to ground using the screw driver? Ive never thought of this method, but wouldnt you have to crank the motor over, you said just put the ignition on and it will spark, something like that..... More thoughts here? I figure possibly the distributor being backwards might be causing this..... Has anyone encountered this before??????
Thread Starter
Burning Brakes
Joined: Apr 2000
Posts: 959
Likes: 1
From: Lemoore CA
Re: HELP NEEDED!!!! 383 Wont start... (Nomar116)
Also, does it matter where the firing order starts... Im using the 2nd terminal clockwise past the electrical connections on the side of the cap. Im pretty certain the order is correct...
Melting Slicks
Joined: Aug 2000
Posts: 2,388
Likes: 42
From: Murrysville PA
Re: HELP NEEDED!!!! 383 Wont start... (Nomar116)
You mean the valves were set 3/4 turn past zero lash right? Are you sure you have the ESC bypass wire hooked up? You only disconnect this wire to set the timign after the motor starts and warms up. Do as the person said above making absolutely sure the number one is on TDC. Then place the timing mark on the damper to zero. Install the distributor so the rotor is pointing to the number one and verify that the firing order is clockwise from number one. If your plugs are wet from fuel, you may have flooded the motor. Hold your foot to the floor while cranking. This will turn off the injectors and pump that excess fuel out. Let us know!
Jason
Jason
Thread Starter
Burning Brakes
Joined: Apr 2000
Posts: 959
Likes: 1
From: Lemoore CA
Re: HELP NEEDED!!!! 383 Wont start... (89vette)
Yes 3/4 past zero lash. I have no idea what the ESC bypass wire is.... Maybe thats the problem?? As for the fuel problem, this could also be possible. We primed the motor by cranking without spark plugs, thus the engine did flood actually also sent fuel out the spark plug holes onto my headers etc... It reaked of gasoline... Could either of these be my problem. I would rather not make the first start up with the pedal floored however. It was Sunday that we were trying this and I wont be trying again until Tuesday night.... That should be enough time right? Again when the motor cranks, the rotor and entire assembly spins easily, however there is some sort of whine, and combustion occurs until the spark plugs backfire into the intake. Im still learning about all this, so some of that may not be entirely accurate... But please keep the responses coming..........
Safety Car
Joined: Mar 2000
Posts: 3,620
Likes: 2
From: Hillsboro OR
Re: HELP NEEDED!!!! 383 Wont start... (Nomar116)
Make sure your firing order is correct and #1 is on the compression stroke when rotor is pointing to #1. Remember that the distributor spins clockwise. Once your sure the firing order is correct, readjust each valve by following the firing order. Start with #1 and do each one after turning the crankshaft 90 deg. clockwise.
If is its still backfiring, the timing chain may be off by a tooth. You'll have to pull the timing cover off and put the chain assy on correctly.
Good Luck
If is its still backfiring, the timing chain may be off by a tooth. You'll have to pull the timing cover off and put the chain assy on correctly.
Good Luck
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Thread Starter
Burning Brakes
Joined: Apr 2000
Posts: 959
Likes: 1
From: Lemoore CA
Re: HELP NEEDED!!!! 383 Wont start... (Nomar116)
Wow... Did I just find the problem???? The car is not completly connected up, a few things here and there are not connected. One of which is the knock sensor... evidently also known as the ESC knock sensor.... If thats not connected, is that causing this problem???? That will be a heck of a relief. As a side note I really need to purchase a need connection for the knock sensor, mine is very much broken and I was going to use heat shrink tubing to keep it attached.
Paul
Paul
Melting Slicks
Joined: Aug 2000
Posts: 2,388
Likes: 42
From: Murrysville PA
Re: HELP NEEDED!!!! 383 Wont start... (Nomar116)
A knock sensor disconnectred will not cause the car not to start. If you have fuel, you need to verify spark. If you have intake backfires then I assume you have spark so then I assume timing. Before you start tearing your motor apart, play with the timing first. Do set it to number one like I said above and verify all plug wires on correct. Holding your foot all the way to the floor is clear flood mode. Did you listen when I told you that before? With it to the floor the injectrors do not fire. Its to rid the combustion chamber of excess fuel. How would this hurt your motor? The ESC bypass wire is a tan/black wire near teh brake booster. You have to know all about this wire to properly set ignition timing.
After you get the motor running, adjust the timing by hand so the motor sounds nice at idle. Bring it up to temp and disconnect the ESC wire. Now use your timing light an set the timing to 6 degrees BTDC. Turn the motor off, reconnect the ESC wire, disconnect the battery to reset the ECM (it will set a code when you disconnect the ESC wire) and you should be good to go.
After you get the motor running, adjust the timing by hand so the motor sounds nice at idle. Bring it up to temp and disconnect the ESC wire. Now use your timing light an set the timing to 6 degrees BTDC. Turn the motor off, reconnect the ESC wire, disconnect the battery to reset the ECM (it will set a code when you disconnect the ESC wire) and you should be good to go.
Racer
Joined: Sep 2000
Posts: 294
Likes: 0
From: Princeton Texas
Re: HELP NEEDED!!!! 383 Wont start... (89vette)
This may sound stupid, but do you know that the cylinders on chevrolets are numbered 1,3,5,7 from the front of the car on the drivers side and 2,4,6,8 from the front of the car on the passengers side. Some other manufacturers are different IE Ford 289.
