1980 RX7 catch bottle help

[BruceG]

Ran my newly aquired RX7 at limeRock on Monday for some test and tune. Has a 16gal Summit fuel cell. Going thru the left hander, I was spewing fuel out and got black flagged. Discovered that there was no catch bottle attached to the end of the hose coming off the cell(duh)!

My question is....do I need to route the hose up in the air before entering the bottle, is thre a fitting I can use to pass air(but not fuel) out of the tank and finally what should I use for the bottle and where should I locate it(obviously, away from the exhaust).

Thanks for any help!!

[mbuskuhl]

Do you have a vent check valve? If not, you should get one. There are a couple options. They prevent fuel from coming out the vent hose in the event of a roll over and should help keep the sloshing to stay in the tank rather than the hose. http://www.pegasusautoracing.com/pro...asp?RecID=5568

Run your vent hose up high, I had a similar problem you did with fuel coming out the vent hose before. I ran the vent hose up the rear roll cage brace to the main hoop and then all the way back down before it exited behind the rear wheel well on the NON - exhaust side. No matter how hard you corner the fuel isn't going to be forced up the vent hose high enough to escape, yet it still allows air to vent when necessary.

[tom_sprecher]

I have a one way valve that vents air into my 15 gal Fuel Safe cell as the fuel is consumed. It is in the bulkhead fitting at the hose attachment point on the filler plate. Then I put a loop in the hose with the end pointing straight down.

Never had an issue.

[BruceG]

Thanks Mark and Tom. Just the info I needed! Car ran like a raped ape until I got the meatball.

Thanks again,

Bruce

[dickita15]

Bruce
Even with a check valve I was having enough leakage to be seen from station. As you suggested I ran a longer hose and looped it up and it has been fine. I do not think anyone runs a catch tank on their fuel vent.

[BruceG]

Hi Dick

Thanks for the info. Monday was a bad day. Because SCDA has a muffled event, I knew that my ITA RX7 was way too loud. I ordered the short Supertrap from Pegasus, has my mechanic locally butt weld it to the tip of my tail pipe. He placed the outer flange on backwards, so it shut down the exhaust pipe. We took it off to mount it correctly,it has lock washers which stripped the screws when we removed them so we were unable to install it again! I ran 2 laps without the trap and the car ran great but I was spewing fuel in turn 3 so got the meatball. When I tried to fix the fuel problem and go back out, they wouldn't let me out because of noise. There was a Nascar Craftsman truck running unmuffled and I guess Skip Barber could hear the noise all the way in Sharon due to the low cloud cover...sp he called. Lime rock gets fines big bucks frp the town for excess noise.

Bruce

[lateapex911]

My rule is to NEVER run an RX-7 at a muffled event. It's pointless. Really, unless you are just checking basic operation, leaks, wheels falling off, etc. Muffling these things kills so much power it makes the testing useless. For that reason, I only do the LRP unmuffled test days, or go to the Glen.

[billf]

I also am one who had venting issues with the cells. My solution was similar to the one listed by mbuskuhl. I had to route the vent tube (which was on the right side of the cell) to the opposite side of the car, then loop it up high to the side of the vent, then drop down to its exit on the right side of the car.

Intention was to reverse the direction of the flow of fuel IN the tube when cornering, ie. vent on right: when cornering left, flow was out of the tube to exit on right.

Now when cornering right, the flow MUST flow to the left, and cannot make the right turn in the tubing (anti-lateral force) to reach the exit (which was on the right).

Had my issue during two day driver school. Black flagged, resolved for Sunday.

Good luch with yours.

Good racing.

Bill

[BruceG]

Thanks Jake and Bill for the info! Hope this fixes the issue. My Buddy was right behind me going into the left hander and could see the result.