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View Full Version : Help - weird CRX fuel leak



boywonder
03-30-2009, 11:40 PM
OK, so I took the car out this past Saturday for the first time and ran a track day at Putnam. The car was fine (driver needs work, especially in the rain...) however tonight I received a phone call from my friend, the car is currently in his garage awaiting its annual tech this weekend, who's wife found the car leaking fuel tonight. :o

Hopefully Jim will hop on here and fill in the details as he was the one who actually saw where it was dripping from, but it sounds like it was leaking from the canister on the firewall. Anyone seen this happen before? This is the first time the car has leaked any fuel in the 2.5 months I've owned it and it still has the stock mechanical fuel pump . What would cause it to spontaneously leak two days after it last ran?

bonespec
03-30-2009, 11:48 PM
canister = fuel filter?????

20 year old line might have finally had enough.

Wait until you get the leak on the rubber line at the gas tank.

boywonder
03-31-2009, 10:40 AM
Not the fuel filter - see the photo, I guess it was coming out of that canister, which was mounted on the firewall.

http://placidchaos.com/stuff/leak.jpg

boywonder
03-31-2009, 10:45 AM
Not the fuel filter - see the photo, I guess it was coming out of that canister, which was mounted on the firewall.

http://placidchaos.com/stuff/leak.jpg

Sounds like there was fuel in the red hose (fuel return line?) but not in any of the other three hoses, which go to the carb. Any ideas why fuel would be randomly backing up from the return line while sitting on the trailer untouched for two days?

jay05
03-31-2009, 10:52 AM
That may be a charcoal canister for emissions. I had mine split on the VW after a race while sitting in tech. It clogged and over pressurized and dumped fuel on the ground. If it is take the system out. You may not need it. Al Gore wouldn't be happy though.

jumbojimbo
03-31-2009, 12:21 PM
Yes, that was quite exciting last night to find 1/4 cup of gas on the garage floor.

It was hard to tell, the clear orange hose in the picture is on the bottom of the canister. I could not tell if the fuel was dripping out of the hose or if it was coming from somewhere else and then ending up running down the hose.

there was definitely gas on the outside of the hose, but the gas could still have been coming out thru the hose and leaking around the connection.

At the worst it was dripping pretty good. more than a drop a second, it was running off the bottom of the canister and then over the torsion bar mount.

when i pulled off the little tiny hose that runs from the canister to the firewall, which i assume is the fuel return to the tank, some gas did come out of that hose. Not a lot, a teaspoon? That hose is pretty wimpy so I assume that there is little pressure going that direction?

when i pulled the canister off the firewall, a little gas came out of it, but not much.

so where was all the gas coming from? is it possible it was siphoning from the return line and pulling gas from the tank? And when I pulled the hose I broke the siphon and it stopped pulling gas.

Or did the gas come from the canister and it just happens we noticed it not long after it started leaking and it stopped when empty?

Right now everything is unhooked and all the lines are plugged. Is the the final answer? just remove that altogther? is there any point to this, other than making Al Gore happy? will it be a problem if the return Line is plugged?

jumbojimbo
03-31-2009, 12:23 PM
Or do I have this completely backward? is the point of the canister to capture fumes from the gas tank and send them TO the carb?

Greg Gauper
03-31-2009, 02:55 PM
I had a similar problem when I first built my car 10 years ago and I wonder if you made the same mistake I did....

There are three fuel lines that come out the firewall.

The largest of the three lines is the supply line that goes to the fuel pump.
The other two lines are the fuel return line and the fuel vent line.

When I built the car, we pulled everything out of the engine bay for painting and then put back just the stuff that needed to be there. I removed the vapor canister and put a used coolant bottle in it's place as a catch tank (BTW - a Honda coolant bottle has the exact same 'V' as the vapor canistor and makes for a perfect catch tank and they are cheap from the boneyard).

I left the vent line open, and connected just the return line. But it turned out I accidentally crossed the return line and vent line. So I actually had the return line exposed at the fire wall. I didn't catch this until the first time I filled up the tank in the morning. As the ambient temperature got warmer, the pressure in the tank expanded and started to force fuel out the return line creating a leak.

Retrace the lines and make sure you don't have them crossed up. After I swapped the lines I never had an issue with the open vent line at the firewall.

BTW - I also relocated the clear plastic suction filter from the rear to the engine bay by cutting the hose from the firewall to the fuel pump. This makes the filter so much easier to inspect and service than the stock location where it is buried under the car back by the fuel tank.