Horrible mpg horrible gas smell stumped.

[Stupidquestionspro]

Well I’ve noticed my gas mileage has been dropping substantially this last rank I almost cried to find out it was 8mpg which I think everyone will agree is insanely low for a SBO 350 and couple month old carb.

Summit 600cfm carb idle screws are only I believe 3 turns out.

Fairly certain I’m having a fuel boiling problem but I’m not sure if that’s where all my gas is going.

I’ve pretty much had to stop parking in the garage Becuzs the raw fuel smell is so overwhelming and starts to seep in the house. I can’t find a leak or signs or a leak anywhere and I’m not sure how to fix that.

why are my secondaries gold?




Sent from my iPhone using Tapatalk

 

[pontiacgp]

this may be a stupidquestion but have you crawled under the car to check the fuel lines and tank?

 

[Stupidquestionspro]

A while ago but I should again. I also just replaced the gas cap just in case. I’m hoping my fuel pump isn’t leaking into the crankcase.

This has always been a Florida car and was under coated after purchasing by the original owner so I doubt it is the lines but maybe it’s the tank or I believe rubber connects the hard lines to the tank so maybe it’s that although I believe the gas smell comes from the engine compartment and I haven’t seen any drips spots or otherwise.

I wonder why the secondaries are that weird color too. Also worst I even lowered the float level to only a quarter window.

I think part of it may be the fuel is boiling and the excess pressure is pushing the needles out of the seat and letting fuel in because when hot if it sits for more than 40 minutes it sucks to restart.

It also idles badly and has a little less pep when hitting the gas when hot as well but it was weird I was making sure the secondaries worked the other day and after punching the throttle to WOT 3-4 times in park the idle got way smoother and the pickup was better. I’ll need to pull and read my plugs soon I know that will help.

I did a fuel pressure test a while ago and I believe it gave and held 6psi


Sent from my iPhone using Tapatalk

 

[Stupidquestionspro]

is that what it would look like if the fuel pump was leaking and it was evaporating off?


Sent from my iPhone using Tapatalk

 

[Ribbedroof]

this may be a stupidquestion but have you crawled under the car to check the fuel lines and tank?

Always a good idea to replace the hoses on a 30+ year old car!

 

[melloelky]

Always a good idea to replace the hoses on a 30+ year old car!

He's rite,believe it or not,over time rubber hoses allow fuel to permeate through them.it's worth a look.

 

[lilbowtie]

When your idling look down the carb and see if fuel is coming out the front or rear venturi - when you stop the engine check again to see if the front or rear venturi is bleeding. Three turns on the idle screws seems a bit much, I always start at 1.5 turns. You also need to make sure your carb blades aren't open too far and your not using the idle curcuit.
make sure the idle transfer slot setting is right.

 

[Stupidquestionspro]

When your idling look down the carb and see if fuel is coming out the front or rear venturi - when you stop the engine check again to see if the front or rear venturi is bleeding. Three turns on the idle screws seems a bit much, I always start at 1.5 turns. You also need to make sure your carb blades aren't open too far and your not using the idle curcuit.
make sure the idle transfer slot setting is right.

I actually already reset the transfer slots and blades problem was to get the secondary transfer slot square the fast idle had to be practically completely loose which didn’t work so I tightened it a bit and at 1.5 it runs like sh*t for sure. I’ll have to check and see if it is bleeding.


Sent from my iPhone using Tapatalk

 

[Stupidquestionspro]

Sooo definitely gonna have to do some serious work soon because stuffs happening now and i am beyond lost on what’s going on.

The other day it actually knocked or rattled once or twice after I shut off the ignition. It’s been rattling some on start up and has died a couple times idling. And of course is terrible to
Hot restart.

Also have noticed I’m fairly certain my ac clutch isn’t cycling I believe it is constantly engaged as well my temp is getting higher than before with a brand new water pump and 160 thermostat only when sitting still idling. That’s probably my fault though because of pure laziness and to cut costs I haven’t bought anymore coolant so it’s mainly water so I assume it’s boiling or something.

So needless to say my DD project has thrown some new awesome problems at me.


Sent from my iPhone using Tapatalk

 

[fleming442]

What octane fuel are you running? If it's dieseling on shut down, the gas is trash, or you can try knocking a few degrees of timing out. Been there, done that (it was the gas).