[escaflowne]

I just added a fuel pressure gauge to my 68 firebird 350. I noticed that the reading at startup jumps all over...ticking from like 3-5psi...it will smooth out a lot as the Rpms come up...it is a stock mechinacal pump pretty new so i am a little confused...I also noticed while under the car that with over a 1/2 tank and the car parked on a nose down decline it leaks fuel...??? ok I know I have some kind of fuel line leak but is the erratic pressue and the HORRIBLE bog off idle all the same issue??? as simple as seal the fuel line leak the pressure settles down and the bog goes away???I was thinking about it last night and it seems to add up but it seems too simple...am I missing something???

[steve]

i always start with the simple easy and cheap fixes first. mostly because i am simple easy and cheap . fix the fuel line leak and see what you get.

where is it leaking from ? you might just need to re-torque. every time i do carb work i have to retighten fittings to seal them good. for some reason the first torque nevr gets it done. i think i do that cause i am afraid of overtightening things (i have a history of that......)

[BVR421]

While you are waiting for the car to burn to the ground, (8--)
you might want to replace the flex hose at the gas tank pickup and at the frame to fuel pump connection. If those hoses havent been replaced in the last few years, they may be very badly rotted and cracking, leaking both gas and sucking air.
Modern gasoline additives require better quality fuel hose than in previous years. The old rubber hoses just wont last with the nasty stuff in the new gas. When I first got my Bonneville, with a full tank, I had to park nose down in the driveway, the other way and the hose would leak out the top 2-3 gallons.

[BVR421]

Originally Posted by steve

i always start with the simple easy and cheap fixes first. mostly because i am simple easy and cheap every time i do carb work i have to retighten fittings to seal them good. for some reason the first torque nevr gets it done. i think i do that cause i am afraid of overtightening things (i have a history of that......)

Steve, we must have gone to the same ShadeTree Mechanics School!

[escaflowne]

Mine leaks nowhere that bad...if parked on a decline it may leak in a drop ...drop ...drop fashion for like 10 min or so if its hot out but if flat or les than a half tank no leak at all...It has a new tank and new rubber hoses in the back...it seems to be in the steel lines that go over the crossmember .I am thinking the vent line but not sure...I replaced all the rubber around the fuel pump and line to the carb ...just need to fill up and lift the rear with a jack to check...If it is a bad hard line can you get pre-bent replacements or can you just cut the bad portion out and replace with like steel braded line???

[Ron H]

Yes PY sells the fuel line kits. The mechanical pump, pumps in pulses so your fuel pressure gauge will show a pulse. I bet you are sucking in air which is reducing the fuel pressure. The bog could be the carb leaning out due to lack of fuel getting to the bowls.
When does the bog happen? Is the car really hot? While cruising and punching or just from a stand still?

[escaflowne]

The bog is from a stand still...but it is it a bit slugish While cruising and punching... can the lines be spliced in with braided line as a matter of testing or is it better to order ithe whole thing from PY?

[Ron H]

If you want a stock replacement, order the correct lines from PY. You can always run a different line from the tank to the front.

[escaflowne]

So replacing the stock hard line with a braided line would cool in a street car??? The reason I ask is that I have plenty of steel braided line from another project and if I can save the roughly $120 for the stock replacemnts that can be spent on other things ...like into the new transmission fund

[escaflowne]

OK so I found the issue it seems....after looking over the fuel line routing in the service illustrated manual is found a section of rubber hose i did not know about...Tucked away by the wheel well and under all the AC crap is a section of hose...I reached under the car this morning and is is stickey/ gooy and has a well spongy feel...it also has the factory clamps on it unlike the bands like all hte new softline...I am going to replace it tonight and go for a ride the carb will probally be way rich and need a retune but we wil see...