Holley problems

[47convert]

I have a 66 ELCamino with a 292 cu. in. sbc in it that runs fantastic, normally. A couple of days after filling up with gas the other day it started to run rich. When I pulled the air cleaner off for a look, I found gas drizzling out of both the primary and secondarys of the carb at idle. I ended up pinching off the tube that fills the rear bowl so I could get home. Even then it was really rich. Does this sound like bad gas possibly holding the needle valve open? Can I get away with just clening the needle and seat assy? I have changed the filter. I have an old Holley that I can steel the tube from.

[Charlie Chops 1940]

Giving the carb a good cleansing would be my first step. Holley's tend to be very sensitive to the scum that comes with dirty gas. I have a 600 that I've been using for close to 20 years and every 3 or 4 years it seems it needs this ritual. Rebuild kits aren't overly expensive but you will at least need bowl gaskets and the transfer tube o-rings.

Charlie

[wayne petty]

i agree that crud in the fuel will make the carb leak...


you can in an emergency  when the carbs flood...  

get the engine started... keeping it revved up.. pinch off the suction line to the fuel pump... just before the engine dies... release the line...  the surge of fuel will sometimes clear the junk out of the needle... this usually works better on the primary side..

how it works...   the fuel level in the float bowls drops... opening the needle and seat wide...   you have stopped the fuel ..  so just before the carb is empty...  releasing the fuel will surge into the carb through the open seats...  usually clearing out the trash...    sometimes you have to do it twice or three times...


it might be really time to examine the fuel filter...  or the sediment from the bottom of the float bowl...  with a magnet..  its probably rust from the bottom of the tank...    from the gas station.. or from the fuel lines...

putting a quality fuel injection fuel filter at the inlet of the fuel pump really reduces the amount of rust that gets through the fuel pump..  

this rust and sediment also affect the fuel pump....   ever have a car start just fine after an overnight sit... then die after about 15 seconds??? then you have to crank and crank it to get it to start again...  sediment in the check valves in the fuel pump....   when installing a new fuel filter in the suction line...  pull the output line off and crank the engine with a hose directing the flow into a plastic bottle...  the full flow will clear the check valves inside the fuel pump usually....

hope this enlightens a few...   without the use of matches...

[47convert]

Great idea! Thanx Wayne, but I've already removed the carb and changed the filter. I'm going to try to just clean it up and change the needle and seats. Couldn't find a complete kit and nobody can get one for me before Monday so we'll see what happens - thanx again.

[C9]

One that's worked for us was to remove needle and seat, rinse it out with a garden hose, install and set the floats.

Had a good sized chunk of grit holding the primary needle open at the races one night.

This in a filter-less door slammer . . . that had a filter next race.

(Holley's externally removable needle and seat set up is great.)


Check fuel pressure as well.
Holleys don't seem to have fuel pressure problems like Edelbrock/Carters do, but they can creat trouble if pressure is too high.

Install a regulator.
Do yourself a favor and install a fuel pressure gauge with isolater.

Having a few gauges for on-board diagnostics is educational as well as helpful.

[47convert]

Thanks everyone, for the suggestions. After changing the filter and cleaning the screen, blowing out both bowls and the needle/seat assemblies it worked great for a week, then I had the same problem occur when my brother was driving it to a show. Hard to drive 2 cars now that my little coupe is on the road. I found the same problem. This time I cleaned the first little glass filter that's just ahead of the pump, changed the aluminum one again after the pump and installed new neoprene hoses just about everywhere, leaving only a short section at the pick up/ fuel sender because it was new a few weeks ago when we had a new gas sender put in. I've only driven it about 3/4 of an hour since, but it seems to be good. I'm going to keep a close eye on that glass filter since it's the first line of defence and it was full of red stringy crap that I think is silicon seal. The guy that changed the sender for me may have installed a little sealer around the gasket surface.

[wayne petty]

about the glass fuel filters with the removable element...

there are 3 different count screens for them course, medium, and fine... almost all of them are too large to catch anything but the largest crud...

at the parts stores,,, there are several versions for fuel injected motors... with super fine paper elements... that will catch almost everything...

look for some for mid to later 80's ford fuel injected cars... yes ... they are set up for the horse shoe type of quick connects... usually around 10 to 15 bucks...  there are a bunch of part numbers that will work...

leaving the glass filter where it is for fuel verification.. and stashing the new larger filter down by the tank.. or right before the fuel pump... so no corrosion from the fuel line will get into the mechanical pump....

glad that you were able to find the problem...

[47convert]

Thanx Wayne, for the great advice now and in the past .