88 4AF fuel pressure? - Toyota Nation Forum : Toyota Car and Truck Forums

Noidly1 · 01-11-2009, 08:26 PM

Sorry if repost, did search, couldn't find...

On an 88 4AF engine w/16340 carb, what is the fuel pressure supposed to be?

I am in the middle of rebuilding the carb and am trying to bench set the fuel level and am having probs setting it with a "clacker" style electric pump.
The level keeps going high. When I gravity feed the carb the level is low.

Apparently the needle, being sprung, is pressure sensitive.

Any help would be greatly appreciated...
Thanks.

Flashmn · 01-12-2009, 05:54 AM

IIRC it should be around 6psi for the stock carb....

Gravity feeding would actually work, because the float controls the needle valve, not pressure. If you over pressure it your carb will flood.

eage8 · 01-12-2009, 09:42 PM

Quote:

Originally Posted by Flashmn

IIRC it should be around 6psi for the stock carb....

Gravity feeding would actually work, because the float controls the needle valve, not pressure. If you over pressure it your carb will flood.

yup, stock its 6psi. I just went out and got a fuel pressure regulator today for my weber install (they're supposed to run at 2 psi)

if you can't get it high enough, you can just run the electric pump with pressure regulator.

Flashmn · 01-13-2009, 04:13 AM

I ran with the stock mechanical pump on my weber installation, just added a pressure regulator for it.

eage8 · 01-13-2009, 10:14 AM

Quote:

Originally Posted by Flashmn

I ran with the stock mechanical pump on my weber installation, just added a pressure regulator for it.

cool, that's what I'm planning.

Theron · 01-27-2009, 07:15 PM

What type of FPR are you using? 2 psi?? Is the stock pressure ok?

eage8 · 01-28-2009, 10:16 AM

Quote:

Originally Posted by Theron

What type of FPR are you using? 2 psi?? Is the stock pressure ok?

for a weber? no, the max you can run them at is 3 psi.

I just went to autozone and got a spectre FPR for $25

Theron · 01-28-2009, 11:11 AM

Whoa. I've been running my Weber 32/36 with the stock mechanical fuel pump at the stock pressure.
I have noticed some discolored spots at the base of the carb, but no big leaks. I wonder if this is the problem to my worse fuel millage?

eage8 · 01-28-2009, 12:36 PM

Quote:

Originally Posted by Theron

Whoa. I've been running my Weber 32/36 with the stock mechanical fuel pump at the stock pressure.
I have noticed some discolored spots at the base of the carb, but no big leaks. I wonder if this is the problem to my worse fuel millage?

I would almost guarantee that's your problem, sorry I didn't even think of mentioning that in your other thread.