can a leaking exhaust choke block off plate cause a back fire

 

If you are talking about the plate on the intake crossover where the choke heat tubes go, yes. It doesn't actually cause a backfire, but the leak lets you hear it MUCH more loudly. Normally, these pulses would be muffled by the heavy cast iron.

 

I'll add that I'm talking about an exhaust backfire. If you are talking about a carb backfire, then no. Rule of thumb it that a backfire through the carb indicates a lean condition. Through the exhaust indicates a rich condition or a leak.

 

it wasn't back firing until the chock block off blew a seal

 

ive got the a/f mix as rich as it can go and the choke as well could it be the carb is too small

 

Too small a carb won't cause a backfire. Do you have a carb or exhaust backfire? Have you checked your timing?
You should consider combining all 3 of your threads to make it easier to follow.

 

how do I combine the threads ??

UPDATE
the friend who did my timing moved my plug wires causing it to be way to retarded I advanced it and no more back fires but I still have to fix the plug wires

 

If the timing is right, it doesn't matter there position as long as they are in the right firing order.
No idea how to combine threads. Maybe a moderator can help.

 

got it running its back spinnin tires

 

Good, so what did you do?

 

advanced it till it was at 0 it hits 18 at wot

 

Thats still not enough advance.

 

I'm going to work on it more after my trip I just need it running good enough to get me there and back and its running like a its tail is on fire plus my timing light died and on a side note the engine runs best at 0-8 initial I tried for 12 and it got temperamental

 

You'll need a good tail wind to put that fire out on your trip!!

 

very funny but to everyone who commented I do appreciate the help this engine is still a learning curve for me thank you

 

Put-er-ther, we are all here to try and help. Its good to hear that your into Oldsmobiles at your age!!
Don't give up and sell your Olds, it will be the best car you'll ever own. Also, this is the best site for help and support while your still young and trying to learn.
Cheers
Eric

 

i

eric I love anything from back when horsepower was king and tuning a car wasn't typing on a key board my first hotrod was an 87 firebird then a 90 Camaro*( rest in peace ) and now the delta I love a good American muscle car my next is probably gona be a 67 mustang

 

Hey now your crossing the line when you bring up Mustangs haha!! By a nice 67 Olds if your into the 60's stuff, forget the mustang!!

 

hey now aint nothing wrong with a eleanor mustang or the dukes charger

 

No no no no, you look twice as nice in a AMC Pacer

 

It's great that you love the old cars that you can actually work on. I'm sure I speak for most on here when I say we are very happy to help out someone who wants to learn or has a problem no matter what age they are.