1987 RX-7 GXL
s5 turbo shortblock, trans, and turbo. s4 manifolds and accessories
front mount intercooler

I change my oil and start the car to make sure the oil isn't leaking from the newly installed filter and I see clear drops coming from near the oil filter. I stick my hand in there, smell my fingers, and its fuel. I have a hard time smelling gasoline after owning this RX-7 for so long so I needed to get it close to my nose. I look and theres a couple lines that I think are fuel. I figured one of the radiator style clamps was leaking, so I went to take them off and retighten them, when I found a third nipple that was unoccupied. I look around and sure enough theres a hose that isn't going anywhere. I turn the car on but then I didn't see the drops of fuel again, but I doubt the one radiator clamp I retightened fixed the issue. The drops aren't coming out of the hose going to nowhere or the unoccupied nipple.

I just got the car back maybe 3k miles ago from having the engine rebuilt and all the work was done by the shop. The only issue that I know of is that when I got the car back, there was a line going from the charcoal canister (pictured) to the other side of the engine bay and a vacuum hose was dangling there by the oil filter, so I took that line off because the engine builder said I didn't need it, but that it went somewhere over there. So I don't know if that unoccupied nipple I mentioned on the previous paragraph is where the charcoal canister line goes to or if its for the unoccupied black hose pictured.

Thanks for your help and please give me any sort of advice or knowledge that you have.

This is where the area I'm talking about with the fuel leak is.


Here is a close up of the three nipples, with the top nipple unoccupied.


Here is the area for the hose going to nowhere.


Here is the hose itself.


And here is the line from the charcoal canister that I took off.


Heres my questions.

1) Are these two lines with the radiator clamps around them for fuel?

2) Is that third unoccupied nipple for fuel?

3) Does that black hose hanging connect to that unoccupied nipple?

4) Should fuel be coming from that black hose hanging there?

5) Where does the line coming from the charcoal canister connect to?

 

Holy cow I didn't know those pictures would be so big. Here are smaller version of the above pictures in case you can't fit them all in your browser:


This is where the area I'm talking about with the fuel leak is.


Here is a close up of the three nipples, with the top nipple unoccupied.


Here is the area for the hose going to nowhere.


Here is the hose itself.


And here is the line from the charcoal canister that I took off.

 

holy **** this sure as hell beats the blurry cell phone pics we normally get. ***** in focus and everything!

 

well good news, it's an easy fix. that line is the return line from the charcoal canister to the fuel tank. it ventilates pressurized air in the fuel tank and scrubs the hydrocarbons out of the tank. there is two green hard lines that run along the firewall from the canister side to the inlet/fuel filter side. the larger of the green tubes is the one that requires the connections to be completed from said canister to the nipple. hope this helps!

 

Sorry, the larger of the two green tubes

 

^ Thanks man, so now I know where that firewall hardline and open nipple under the throttle body elbow goes.

Ok so where does that black hose connect to then? Its connected to a nipple in the intermediate housing I think. Its under part of the rats nest (or apart of it maybe).

 

If it's the right by the oil fill tube inlet it's the crankcase vent. Used to go through a check valve back to the original intake tube. Pretty sure it's routed in the second hardline with the oil supply to the turbo.

 

hope this helps with some trouble shooting. It's the series 4 diagram. Red is hoses, yellow is hardline.

1. yes
2.3.4.5 no (but fuel mixture/condensation will be present)
if it is the hose from the hardline on the firewall, yes. if no, then refer to the diagram

If you ever wondered why your used oil smells a little like gasoline, that little hose is why. it pipes the fuel contaminated air into the oil filler via a hose (refer to diagram). hooray for weird *** emissions equipment

https://lh3.googleusercontent.com/_1...ww/s912/.1.jpg