[thenewguy]

alright .. I have a 69 chevelle with a 350 in it .. and for some reason lately it has been back firing and I think burning my air filter intake .. its really wierd .. like if I am at a complete stop and hit the gas it seems to cut out for a second then really pick up in speed .. I was just wondering if this was something serious or what and if so is there a way to fix it .. I am a the new guy to chevelles so any infomation is good infomation .. thanks

-the new guy

 

[Tomb7us]

Hey im new to chevelles 2!! mines doing it too backfire and stumbling since the rebuild. What kind of carb and so ons whats your timing at?

also i think backfiring throught the carb is either bad timing (firing on the exaust stroke) or i was reading maybe a cam lobe?

[This message has been edited by Tomb7us (edited 10-01-2002).]

 

[SS_Dave]

First of all welcome to Team Chevelle!

You say this started recently.
What has changed that you know of?
Did you have any plug wires off?
Is your ignition system in good shape?

Give us ALL the details

Also, you can search by key words for info
you want. There is tons here.

Dave

 

[Glenn1018]

If it's burning your air filter, it's backfiring through the carb which could mean at least one intake valve isn't closed when it should be (if the timing's ok).

It could also mean an exhaust valve is remaining closed (worn cam lobe maybe)thereby causing the exhaust to exit through the wrong door.

Did you move the distributor setting just prior to the backfiring?

Broken valve springs or sticking valves can also cause this.

Does it do it all the time?

[This message has been edited by Glenn1018 (edited 10-01-2002).]

 

[thenewguy]

alright .. heres the story this car was my dad it was sitting for about a year .. the only thing that has changed is .. I changed head covers .. and thats about it .. I havn't changed much about it .. I changed the spark plugs this last week .. but the problem has been going on for like two weeks and I just noticed when I was changing my spark plugs that my air filter is burnt bad .. I don't think I have changed the distributor setting at all, the car seems to go it in the morning or when just started anytime

my ignition system is in good shape,all plug wires are good and on there, I have no idea what my timing is at

I heard that when its cold that the carb is not all the way open and that if has to warm up before it can let in enough air to burn the gas .. this kinda makes sence because because when you step on the gas at a stop it sometimes just seems to not beable to get enough air for how much fuel is in the engine .. Is that Right ?

oh yeah I just remembered that a couple of weeks ago it was tidling to low and my dad fixed that

other then that I don't remember doing anything to the engine .. last thing this only happens when I step on the gas pretty hard to like get on the freeway or from a stop and speed up .. regular speed driving it seems fine

thanks .. if you guys have any more questions just ask because I want to fix this as soon as possible

-the new guy

 

[d1_bradley]

Advance the timing until it kicks back while cranking. Then retard a tiny bit. No more backfire. Or, I you have a light, set it at 8 degrees BTDC.
Oh, and after you set the timing, set the idle speed.
------------------
Dave Bradley
www.corvetteforum.net/classics/d1_bradley
'69 SS396 ragtop
'33 3W Coupe
'65 Vette BB Roadster

[This message has been edited by d1_bradley (edited 10-01-2002).]

 

[thenewguy]

Alright .. I am the new guy can you do me a huge favor and put what was just said in some easier to under stand words.. thanks alot

-the new guy