TR6 1972 TR-6 Fuel Vapor Recovery System

[dhagerty]

Have placed the fuel vapor recovery system into complete service on the TR-6. The lines to the carbs and the valve cover were in place, but the line from the fuel tank was plugged at the beginning of the steel line at the fuel tank end. Cleaned all that out and this line is now free to the carbon vapor collection tank. Have also installed the oil vapor recovery system by Good Parts (www.goodparts.com) and an electric fuel pump.

The diagrams call for an orfice (restrictor) in the vapor line from the fuel tank to the carbon canister. I cannot find one available from the parts suppliers so I made one with my 3D printer. Taking a shot at the level of restriction I put a 1.7mm hole in my unit. My question is "Does anyone know the size of hole (orfice) required for the restriction or is the restrictor constructed by another method such as baffles." I can 3D print almost anything so find out what was the original construction would really help.

If I get a good design I will put the STL file here on a post so anyone with a 3D printer, or access to one (friend) can print one out.

Thanks

Dean Hagerty

 

[Tr6easyrider]

Does this help Dean.
Measurement are in inches with digital caliper
Length= 0.508 in.
Large shoulder dia.= 0.438 in.
Small shaft dia.= 0.317 in.
Large hole depth= 0.362 in.
Large hole inside dia.= 0.195 in.
Smaller hole inside dia.= 0.095 in.
It is a snug fit into the canister.
TR6 1971 canister.

 

[Tr6easyrider]

Does this help Dean.
Measurement are in inches with digital caliper
Length= 0.508 in.
Large shoulder dia.= 0.438 in.
Small shaft dia.= 0.317 in. Has a small bevel on the end..
Large hole depth= 0.362 in.
Large hole inside dia.= 0.195 in.
Smaller hole inside dia.= 0.095 in.
It is a snug fit into the canister.
TR6 1971 canister.

 

[dhagerty]

These measurements are great. Yours fits directly into the vapor recovery tank, I am making mine to go into the line before the tank, as shown on the Moss and other parts diagrams. The key here is the inside measurement of the actual "pass through" hole that allows the vapor into the canister. This tells you how much vapor Triumph wanted to pass into the carb and thus the actual flow of "air" into the intake system. Will put the final design and measurements on the thread once I get a new one printed.

Thanks for the help.

 

[dhagerty]

Printed new orfice for the line. I noted some significant retuning of the carbs is now required due to the additional air being drawn into the intake manifold. The old vapor line was plugged solid (see above) and the carbs were tuned for the resultant reduced airflow. Today was the first time out with the new orfice and I had to keep some choke in place to have the car perform normally. I cannot attach the STL file as this system will not allow the file extension. If anyone wants the STL file drop me a note to dwhagerty@gmail.com and I will send you the file. This should work on any 3D printer but the particulars for the one I used are as follows:
Printer Prusa I3 Mk 3s, Sunlu PETG filament, .6 nozzle, .3 Quality build setting, 40% infill, requires supports.

The orfice hole is 2.4mm in diameter as this was based from the input provided by TR6easyrider.

If I have any updates will post them with this thread.

Dean