'62 Impala gets a new powerplant
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guys, I'm stumped...I tore the carb down again and reset the rise of the floats back to 7/16" and still have a severe stumble when I depress the gas pedal, worse when the car is hot...starts fine, idles fine, but it falls on it's face before it can accellerate...the motor has a cam in it and I'm wondering if the torque converter is way too tight for the cam...the car idles around 800rpm and feels as if it is loading up...my buddy thinks a looser converter would solve the problem...I'm dealing with a cast iron glide tranny and just can't figure out what the issue is...
Will it accelerate in neutral?
Don't start engine, look down carb and slowly accelerate linkage and watch two shots of gas sprays the minute you open the throttle slow. As I said do not start engine for this test.
she idles fine until I apply a load by putting it in gear, then falls flat on it's face...squirters are doing their job fine...it feels like the cam is wanting more idle rpm which makes sense about the torque converter but I'm not a parts swapper...I'd like to fix it without replacing lots of good parts...the engine revs smooth and strong up to redline and comes down to a smooth idle but stalls when a load is placed on it...
So you are saying it wont idle in gear?
does it have a bunch of slack in the timing chain?
Check egine vacuum ,what do you have? Do you have power brakes? Thinking possibly booster is leaking when you drop in gear if you are applying brakes.
power brakes work like a swiss watch, too good for drrums...I believe vacuum is about 14 in. due to the cam but I'm not sure about that, memory and working on 3 cars is taxing what's left of my mind...as for the timing chain, no rattles of noise of any kind...i've not pulled the cover so I can't say for sure...this car was done right and is fresh...I gotta think the chain would be a long shot with this car, it's almost new...
How is the timing set up, how much mechanical, you using vacuum advance, how is it hooked up?
Can you feather the throttle with your foot on the brake to keep it running?
Can you feather the throttle with your foot on the brake to keep it running?
You mentioned you felt tork converter felt like locking up at 800 rpm . Working in a dealership I witnessed tranny guy finding that issue the minute he put car in gear it stalled it.
Do this for shits and giggle's. Jack up rear wheels on with floor jack on center diff housing. Get in it and leave foot of brake and drop in gear and of course rear wheels will spin . Apply brakes to stop rear wheels and see if you can then stall engine at ldle by stopping rear wheels .
my buddy did nothing but diagnostic work at a large chevy dealership and that's his thoughts...dunno, i'm looking for something more obvious before I go there...he said many 2000rpm converters actually locked up at 1600rpm when tested...add in the cam and it makes sense...running 14 degrees mechanical timing vac advance is hooked up to the vac port of the carb...once under load it just wants to die, occasionally i've kept it running but it just want's to puke on me...
What floats in carb? Brass or the black ones that sometimes get heavy.
I know that for sure ,when I lean over half way is a no no.