TheSamba.com :: View topic

Fri Jul 29, 2016 6:01 pm

I have had my bug for about two months. It has a 1600 dual port in it. PO put a new carb on it about a year to a year and a half before I bought it.

Here is the problem. I can not get the car to stay at a steady pace. Example if I get it to 40 and want to stay there. It stays for about 2 seconds and then I lose power, then after a bit the power comes back. I have adjusted valves, replaced cap rotor and points. Just check fuel pressure and it seats at 6 psi (to high right) Do you have any other suggestions.

Fri Jul 29, 2016 6:27 pm

Humor yourself. Remove the dist cap and grab the rotor. Give it a wiggle /shake. Does the dist drive shaft move forward and back or left to right?. There should be NO movement at all. If there is then your dwell/timing will roam while you are trying to keep the car at a steady RPM. A worn dist needs to be replaced. That is unless Glenn or Tasb can busch the dist shaft.
Good Luck.

Fri Jul 29, 2016 6:47 pm

x2 to 67rustavenger's recommendation for your distributor. You say the fuel pressure is 6psi, that's to high. You can fix that, it should be just shy of 3, 2.8 psi I believe. You can add gaskets between pump and riser or case to decrease pressure. While cruising at xmph, you may be flooding your engine.
Cheers!
Mike

Sat Jul 30, 2016 6:33 am

I also am voting for fuel pressure too high, which is overwhelming the needle valve and letting too much fuel dump down the carb throat.

I had a similar problem with my motorcycle once - turned out to be crud or something keeping the needle valve from closing but it would accelerate fine under WOT (high fuel demand) but as soon as I started steady-state cruise it would run like crap (way too much fuel going into engine).

Sat Jul 30, 2016 12:10 pm

Thanks for the info. This gives me an excuse to go for a electric pump. so fixing the headlights is going to have to wait one more month. Did go and wiggle the drive shaft. I didn't feel any play.

Sat Jul 30, 2016 2:25 pm

Well I mean you still have to diagnose the issue. We are giving you ideas but we're not saying that's definitely the problem. Just a best guess. You have to do the grunt work and find out if that is indeed the problem.