Hey guys. I'm pretty old here on this forum, but its been a long time sice I've posted. Iv'e got a question though.
My little 85 is still running strong, but it was sitting a while. So I cleaned it up got a few bugs out, cleaned out the fuel system etc. But its got this weird problem. When I get to about 4000 or 5000 rpms it just kinda chokes and wont accelerate. Then it will hesitate and with luck, start accelerating normally. I THINK that the secondaries on the carb arent opening, or ar opening a little, then shutting, then opening, etc. I dont know if there is a vacuum leak that wont allow enough pressure to open the secondaries.
Any ideas?
I tried to take off the top part of the carb, but there is some sort of weird invisible bolt besides the 8 little ones and the main one that goes through the body that I cant seem to find.
I've checked to see if it is getting enough fuel, and I believe it is, because I have the fuel pump hooked up to a toggle switch, and I can shut off the pump in mid-acceleration. It does the same thing... sometimes accelerates really hard, sometimes chokes.

 

run it up until it chokes out while it's doing this turn the ignition off and cost to a stop with the ignition still off. open the hood and look in the sight glass on the carb if you see fuel then your getting good delivery if it's empty then you have a feed restriction like the sock in the tank, fuel filter, pump crapping out or screens on the needle and seat in the carb.

 

Fuel line filter is what you check first. Always !!!!

 

well, I don't beleive that the fuel system is clogged for a couple of reasons. 1 its got a new fuel pump. 2 I've cleaned out all of the hardlines. 3 Its got a new fuel filter, and 4 I have nur the car with the fuel pump turned off (remeber , I've got it on a toggle switch), and it made little difference. Sometimes it pulls really hard, sometimes it just chokes. I believe its got enough fuel in the carb. Any other ideas?
I'm thinking of making the secondaries mechanical. It worked well the last time I did it, but the metal wire that I used broke, so Ive got to mess with it again. I just cant get the top part off because of that weird hidden bolt or screw or something thats keeping it on when I take all of the others out. What do you guys think?

 

there are filters in the carb. 2 of them...

the only bolts that hold the carb top on are on top plus the big air cleaner bolt..


i would guess fuel filter, fuel pump or the carb floats are not adjusted properly.
new fuel pump doesnt mean good fuel pump.
maybe your not getting enough psi to fuel the upper rpms.

 

Ok I'm gonna do what you guys said and see if I can get more fuel to the carb. And If I can figure it out, I will make the secondaries mechanical. My last fuel pump was a big old holly, this new one is a bit smaller, I hope I dont need to buy another.

 

heres an easy way to tell if your 2ndarys are working

run the car with the air cleaner lid off. floor it thru 1st gear

you can HEAR them when their open.

 

Ive done that. I can hear them, and see them open just a tiny bit. That's why I want to make them mechanical, but If I could figure out a way for them to open normally, with vacuum pressure, I'd leave them like that. Any ideas?

 

Well, the fuel pump went out yesterday, so it forced me to buy a new one. I got a much better one, with high volume output. So anyway, It still bogs down when I step on it, at about 5000 rpms in 1st gear, and 4000 at 2nd. When it bogs down, I can let off the gas a little, and it picks up a bit and will rev a bit higher, but that's all. I kinda puzzled, please give me your suggestions.

 

Check your accelorator pump. Have someone floor it quickly while you are looking down into the carb (engine can be off). You should see a healthy squirt of fuel shoot into the primaries...