Hello,

I recently parked my 1975 highboy in my driveway, which has a slight uphill. I took the carb off and rebuilt it. I haven't quite been able to get it to start.

Before I rebuilt the carb, it had the same problem. It seems to be getting enough fuel, after cranking it for 30 seconds it starts coming out.

What else could it be?

 

Any rubber hoses in the suction side if old can suck air. They're not bad enough to leak but until the engine fires they can leak enough air to cause a hard/no start. Been there done it.

 

That was my first thought.

What do you mean by that?

 

Have you adjusted the floats properly?

 

I tried to, but not sure I did it right.

I tried to start again today and it got very close, but started spewing fuel. I feel like I adjusted them pretty low (I think they were really high) but I could have done it really wrong...

 

Don't know what carb you're running but there's a wealth of info/how to's on the interwebs. Mebbe look it up?

 

Yeah I'll try YouTube again.

I have Holley 1850-5

 

One more question.

I have a '75 390. If I were to purchase a new fuel pump what would you recommend?

 

Holley 4160 model, 4v...Float adjustment:

Put a rag under the bowl and take off the bowl(s), carefully turn it upside down. (A 5/16" socket works, don't lose the gaskets). The float should be parallel with the (now) bottom of the bowl. Not? With a needle nose pliers, carefully adjust the tang on the float where the needle valve sits. Be sure the needle valve has the little hairpin dealie attached.

 

I would swing with the stock pump. They put out around 7 psi, give or take. More than enough for a stock or slightly built engine, plenty for a Holley.

What makes you think the fuel pump is bad? Any gas smell in the oil - dipstick?

Adjust the floats first, then go from there. One troubleshooting step at a time.

 

I'll take that advice

update you tomorrow! Thanks for your help

 

You're welcome.

 

Alright. I took the front bowl off and adjusted the floats as described (they were pretty far off) after I did that, I threw a little started fluid in there and she started right up. I was by myself in the cab, and it was running very rough. I wasn't able to adjust anything, tried to move around the the motor, but couldn't make it before it died.

I tried restarting it after a few minutes with no luck. Gave it a few hours, still wont start again.

After It ran and tried to start again, there was a bit of smoke coming out of the carb (white and not a lot)

Tomorrow, I plan to take the rear bowl off and adjust it the same, but i am aware this likely wont fix my issues. Any ideas?

 

After you adjust the rear float, turn yer mixture screws all the way in CAREFULLY such that they bottom out. Then back them off 1 - 1.5 turns. this is a ballpark adjustment to be fine tuned with a vacuum gauge later.

You might want to adjust the curb idle a bit higher for now, to be set right later.

Then check the accelerator pump - air cleaner off, engine off, blip the throttle whilst peeking down the carb's throat. You should see two squirts of gas when you do this. If not, it needs replacing.

Sheeit, fergot to ask you to check the power valve when the front bowl was off....A blown PV will make it hard to start and the exhaust will smell from unburnt hydrocarbons.....making yer eyeballs water.

She's not flooding just a-settin' there/turning over, no?

Don't want to give you too many tests as we won't find the illness....but a vacuum leak could be indicated, too,....around the throttle shafts....try those and get back to us.