Home Forums Gear Hunting Trucks and Four-Wheel Drives Anybody familiar with old Chevy big blocks?

And you said you were a Ford man!!

he is. 2 bbl motorcrafts were easier to work on.....

I have my weaknesses.

Ok, I put the fuel regulator on and set it to 5 psi at idle. She chug chug chugged. I then started screwing in the adjustment screws on the carb and she kept running. So as per your prior post Dave, that means I need to pull off the carb and do surgery?

I also checked the oil and there is gas in it now. I check oil level out of habit on it all the time, and before I started it time before this it wasn't that high. It's now reading over and definitely smells of gas. Could that be from the flooding going on?

Edit to clarify it ran with the adjustment screws turned all the way in. They had been sitting about a turn and 1/4 out.

Yeah you are flooding a bowl then, left or right. But you don't need to pull the whole carb. You will have to detach a couple of linkage items. Likely fuel pump linkage (drivers side front corner) and choke linkage, fuel supply line too.

here I stole this photo off the web and drew some arrows pointing to your needle/seat areas.

Must have got a chunk of crud in the line when you changed pumps.

You can try one last desperate farmer trick before taking the top of the carb off.

Start the truck and let it idle with those idle mixture screws closed. Then with the air cleaner off use a good heavy screw driver handle and give a few raps on the 2 back corners of the carb top.

Here and here (red arrows)



That sounds corny as chit but you'd be surprised to learn how many float needle problems can be cured with a few raps directly above the needl/seat areas on the carb lol!!

You'll know if you've got it because the engine will run out of gas and die since you have the idle mixture screws closed.

If it works then you can crank your screws back out to there previous settings and you should be good to go.

Thanks a heap Dave!

I'm assuming the gas in the oil has probably thinned it to the point I'll have to drain that out and replace tomorrow. I'm gonna put the kids to bed here shortly and go smack the top of the carb and see if it works.

Should that not work, will I need to pick up a rebuild kit or might I get by with cleaning it out? I guess that depends on what I find after I open it up probably, I'm just trying to save an 86 mile round trip to town.

If you have to crack the top off the carb just be gentle so not to rip the gasket.

Pull the float hinge pins and lift the needle out of the way. Then with the fuel line disconnected you can try just reverse flushing the seat ports with a can of carb cleaner with the straw attachment. Protect your eyes when squirting that stuff.


Flush em good so the carb cleaner juice flows out of the fuel line hook up.

Then stick it back together gently and carefully. Don't force or bend anything.

Ok I pulled off the top of the carb. Here it the underside of it.


The carb had a lot of grit and dirt in what I presume to be the bowls?


I'm going to suck up the fuel with some paper towels and wipe out the dirt and wipe off the fouling. I was able to keep the gasket intact but for the piece in the middle. So I'm going to try and find the model # on it and get a gasket kit before I put it together. I also forgot to pick up an oil filter so I've got a couple things to pickup in town on monday before I fire it up again.

Is there anything from the photos that looks jacked up? I'm guessing with all the grit in the bowls that maybe some of that migrated to the holes the needles sit in and allowed the fuel to run in?

looks normal to me.

Blow some carb cleaner backwards through the fuel inlets to flush the supply line.

Add an inline fuel filter between the fuel pump and carb inlet.

There was a filter there, reckon it needs replaced. I'll have it all back together tomorrow night. Hopefully I'll be taking her out for a spin.

Well, I cleaned out the carb, and put it back together. Hooked everything back up and went to start it. It wouldn't start. Doh! I still had the idle adjustment screws turned all the way in. So I opened them 1.5 turns each, and she fired right up. I then started screwing them back in to find the sweet spot but it kept running even with them all the way in. That is bad. Right?

The rebuild kit I bought for the carb had a bunch more gaskets and some other little parts in it. I'm wondering should I go to the trouble of figuring out how to take the whole bloody thing apart and replace with the parts from the kit.

The oil had a lot of gas in it. I let it all drain out, then poured a quart of oil in with the plug still out to flush out any gas still in there. By the end of that quart it was running straight oil as far as I could tell.

Thanks,
Jason

Since you got a kit, did you replace the needles and seats?

Or did you just clean the old ones?

I was going to replace them, but the seats were screwed in really tight, and at the risk of buggering them up I just cleaned them out.

So last night turned the fuel regulator as far down as it will go, and got to 3 psi. Then I let it run for just under 15 minutes to warm up. It wasn't up to full operating temp, but it was warm to the touch, and had been plugged in for a full day. I had opened the idle screws up 1 1/2 turns to start it, and after it was warm it turned them in again, but even with them all the way in it still ran.

I'd placed some scrap metal roofing angled off the side of the rear end to try and direct some of the exhaust out of the shop, and boy it wasn't but a couple minutes and the exhaust had sooted them up.

I'm working on a carb issue myself. My problem is with a 4160 Holley 4 barrel. The primairy float bowl gasket started leaking. I picked up a pair of float bowl gaskets yesterday for a 4160 but they weren't quite right. I could make the gasket fit and seal up the bowl but there is an accelerator pump on the front bowl that injects a stream of fuel through the metering block and into the carb throat. The gasket was wrong for this hole, the alignment was off so when assembled the carb just drinks fuel through the accelerator port straight from the float bowl.

I should have my correct gasket today. Apperently there are different variations of the 4160 carb and I guesse wrong on my first try

What's it in?

my snow beast.



I guess I'd change them needles and seats if I were you.

You might need a large slotted screwdriver for the seats, I am unfamiliar with them seats but it's common for seats to be slotted so you can span the seat hole with a large flat screw driver.

Yeah, they're slotted, and pretty soft.

They'll come out.

Big screw driver. doesn't matter if they get damaged removing them, since you have a new set to put back in.

I'd check the float levels as well.

The kit usually includes a little ruler of sorts, usually a square.

Yes, it had one of those rulers. I wondered what it was for.