Help - RSR Clone Won't Start - No Fuel
 

I'm trying to run my RSR clone once each month over the winter. I started it the day after Christmas and took it for a nice run. No problems.

This week I can't get it started. I let the pump run for a minute or so, pump the gas 3 or 4 times. The engine tries to fire, but it will not sustain.

I look at the sight glass on the PMO float bowls and see no signs of fuel in the bowls. As I move the throttle linkage, I see no signs of the fuel jet from the accelerator pump. When I disconnect the fuel line to the carbs and run the pump I get plenty of fuel flow from the pump. When I try to blow into the line leading to the carbs, I get no flow as if the float needle valves are closed.

I don't have a lot of experience with carbs but it seems as if the bowls are empty and the needle valves are closed preventing fuel from entering the carbs on both sides of the engine.

Any experienced help or suggestions will be appreciated.

Tom, if you could, post a picture of the fuel inlet side of the carbs. Its been awhile since ive been into PMOs, or Webers, but it seems odd that both sides of your carbs (left and right bank) are giving you the same problem. But the fuel inlet houses a needle-in-seat valve which is attached to the floats. As the floats rise up, -when the fuel bowls fill up with fuel-, then the needle closes the inlet off until the fuel is used, the level is dropped, and the cycle starts over again.
You can try tapping lightly on the inlets to break them free, as old gas can cause them to stick, and that might work, or you can simply take the inlets off and clean them out. Nothing will come "undone" by doing that.
Let us know..

You probably pegged it - either someone put some small ball bearings in your fuel hose, or your needle valves are stuck closed from old fuel. Try tapping on the side of the carbs near the valves lightly with a plastic hammer...

-Wayne

I agree with Rattlesnake that it would be odd to have the same problem happen in both carbs. The car started and ran fine around Dec 26 and then sat for a month before I tried to start it again. Everything is brand new, fuel cell, fuel pump, lines , filters and PMO's. I hate to take the carbs apart.

However, unless the bowls are full, I should be able to blow into the inlet lines to the carbs. Am I correct on that assumption?

I'll try to free up the needle valves as Wayne and Rattlesnake have suggested and will report back..

Re: Help - RSR Clone Won't Start - No Fuel
 

I'd check fuel flow before and after the fuel filter.

Dead head regulator designs can clog.

Well she's purring away in the garage as we speak warming up for a short run.

Disconnected the fuel line to the carbs tapped on both fuel rails with my rubber mallet. Then I blow through the inlet lines and I get through flow. Button the lines back on and exercise the throttle, and fuel spays from the accelerator pump. Car then starts on first try.

So now the question...What would cause the needle valves to stick and how do I present it in the future?

Thanks a million to Wayne and Rattlesnake.

rsr
 

Glad to hear you got her running.. I would think just some old fuel sitting.. when I am parking my 66 911, boat etc.. for extended periods I mix in sta bil and it seems to prevent sticky issues... not sure if its the "recommended" solution but it has worked for me..

david

Fuel stabilizer would keep the gasoline from varnishing and help keep the needle valves from sticking, but the best solution IMHO is to shut off the fuel pump and let the engine run out of gas, then drain the fuel bowls after engine cool-down. Or just drain the fuel bowls.

Since I plan to take it out for a run once a month over the winter, I think I'll go with the fuel stabilizer.

BTW...Spent the last couple of hour chasing around the back roads here in CT. Boy do I love this car!!!

rsr
 

I probably missed them but do you have any pics.. dont forget the engine room.. thanks...

david

Here's some pics

http://forums.pelicanparts.com/showthread.php?s=&threadid=246556&highlight=anothe r+RSR+clone+project

http://forums.pelicanparts.com/showthread.php?s=&threadid=246563&highlight=anothe r+RSR+clone+project

http://forums.pelicanparts.com/porsche-911-technical-forum/250966-another-rsr-clone-project-track-day.html

rsr
 

Hi,

thanks, I remember your car now.. great shots. anxiously awaiting the spring thaw..

david

Gasoline nowadays doesn't seem to have a long shelf life, even with stabalizer added. EFI would cure sticky needle valves:D

Dean

What do you mean "EFI" (Electronic Fuel Injection??)

Yep that is what I mean.

Dean

I've never seen a stuck closed needle into the seat and I've seen plenty of gummed up carbs. Stuck open is another story.

whatever

Tom,

Did you have those wheels made?