Technical Starting Hilborn Mechanical Fuel Injection

Yep, still here and reading all messages! Just processing it all haha, these comments are great, really appreciate all the help and support.

 

Well it looks like we've found a sprint car guy... I shall PM you! thank you for the help, we will definitely follow this procedure.

 

I do know that it is set up for gas, we found something like an spec sheet from Hilborn with the fuel pressure and all that stuff on it. As for the condition of the lines and the fuel system, that will take some more inspecting. It's been at least 20 years since it last ran so they most likely are not in great shape.

 

Depending on what fuel you are running...alcohol and nitro you have to shut off the fuel, not the ignition or bad things will happen.

 

Wow! Sure would like to know the history behind it.

 

Be real careful starting it up with the old rubber lines. Be sure you have fire protection ready should one (or more) of them spring a leak. It might start up and kinda idle with a regular fuel pump, but would be undriveable. I drove an injected roadster as my only car for three years and as a second car for decades later. It can be done. But it's much easier with a car with no hood -- you're always adjusting something or priming. As for squirting, you can rig an electric pump to prime when needed. I never did. But I made sure after starting it in the morning to shutoff the fuel delivery (and the return) to keep the system "loaded".

 

Man, that coupe is all kinds of cool!!! Vintage muscle hidden beneath bodacious curves!

 

It is set up for gas. We have a sheet from Hilborn that is fifty something years old that tells us everything about the specific unit that is on the car.

 

What a fun project you have there, and with the info sheet, the internet, and input from some "old guys" - it will all come together for the rest of us to admire your hard work and time.

 

Man, that thing is cool.

 

Thanks, that's kinda the reason we build these things...it always means a lot to hear some one likes my "UGLY" car.

 

Late post, but I think I found the kill switch. The flip switch I mentioned earlier is connected to the magneto and it branches off in the middle and connects to the engine block.

 

Do you have the pump flow sheet for it? Truth be told, even if you have one, you should have the pump flowed if you plan to run it as a MFI. You need to know the pump is good and what volume it puts out in order to help set the main pill size. Also, as another person said - I'd not run it if it had older/cracked/brittle fuel lines. These setups can have fuel pressure that is from 50 to 200 PSI in the distribution lines to the nozzles . . . as you can imagine, one hell of a dangerous leak can start at that pressure.

 

I found the instructions from Hilborn. It says the system is set up for gas and 22 lbs of pressure. I can post them if you or anyone else would like to read them.

 

I think you should post them. It would be interesting to see where Hilborn chose to start off the system settings. I know nothing about them, but others will surely comment on it.

 

The 22 lbs pressure is specific to the main pill size they showed. Do you also have a pump flow sheet for the fuel pump? Which fuel pump do you have? It will probably have a PG-150 . . . but there are different sizes of them - the type will be stamped on the pump itself. There are usually designations like #0, #00, #1/2, etc.. Again, if the pump has not been recently flowed, you should send it in and have it checked out, new seals, flow-sheet done, etc..

 

WOW! What a piece of history!

 

No flow sheet. The only thing I see stamped is E-148. Here's a picture.

 

That is some old stuff there! I can tell by the lines that this whole setup has been sitting for a very long time - as you noted. You really should take the pump off and send it to Hilborn to be checked out. Also, you should have the injector and it's nozzle lines checked out - you don't want dry rotted lines spraying fuel all over the place. I can see no reason that it won't run and run well - just make sure everything is in good shape.

You'll want to pull the distributor/mag and fuel-pump drive, make sure everything is loose and well lubricated, etc.. The last thing you want is to shear something off due to things being gummed up. I have one of those early angle drives - they need to be gone through before you attempt to spin the motor over.

Lastly, all the fuel lines from the tank, to the pump and associated return lines as well should be inspected and most rubber ones will need to be replaced. Not only do you not want fuel leaks, but you also want to ensure that pieces of rubber, dirt and other things don't clog up your barrel valve, pill holders, lines, fuel distribution block, etc.. It probably has an old Hilborn fuel filter - pull it apart and check it out as well.

This is actually all normal maintenance stuff - even for a fairly new injector. One should go through all the lines, pressure test them, run fluid through them, etc - every race season.

Where are you located? I'd be happy to do a leakdown on it and help start it if you were close.

 

Pull the covers off the injectors, use a STRONG light down the tubes to check for obstructions, if none, then pull the plugs, squirt some oil down the cylinders, spin it with the starter for 20 sec at time until you see oil pressure (it has a gauge, right?). Be careful not to spin the starter until it gets hot. Check for power at the mag (just hold the power lead while spinning the engine with the starter- NOT), if you have power,
then use a squirt bottle give each tube about a good one second squirt of gasoline. open the throttle and spin it to pull fuel into the cylinders, close the throttle to about 30%, turn the mag switch on and crank it. And wear ear protection. It should fire but not run. As for the rest, they are correct. If it used alcohol, all the lines will flake from the inside and plug the barrel valve and the injectors. And the disclaimer: sometimes they go "BANG" when you do this.

 

We will give everything a very thorough look over and replace whatever needs replacing. We're in NC.

 

Damn. Can't believe I missed all this !! Nothing to add ... maybe another BADASS or something profanely excitable ... and that's really it for me. Great stuff fellas'. Have a great time with this one.