Question-John, Thanks for your help. I was afraid that the compression may be a problem. I removed from the car what I think is the voltage regulator. It is a small metal box completely sealed in exopy and has four wires comming from it. The wires are red, blue, green and brown. Is this the regulator and how does it connect to the alternator? Thanks, Gary (55 year old, retired mechanical engineer)
Followup To
Question -
John,
I am building a vw trike. I took the engine/transaxle from a '73 superbeetle with manual transmission. The bug had not run for ten years. I installed new points, plugs, wires, cap, condenser and coil, and rebuilt the 34 pict-3 carb.
The engine starts easy but will not idle. It runs rough at mid rpm but accelerates good at high rpm but surges at constant throttle. I can keep the engine running smoothly at fast idle if I keep pumping on the accelerator pump. I was considering a new carburetor, but understand that ignition can be a problem with these engines. My timing light indicated timing is in the ball park; 5-10 btdc at idle and 25-30 at top rpm.
I pulled the vacuum lines off the vacuum pot and sucked at each port. The port toward the rear of the car will hold vacuum. The port on the front will not. Is the pot bad?
I have sprayed starter fluid at all the possible vacuum leak spots and no leaks were indicated. I sprayed a little fluid into the intake and can maintain a fast idle. I understand that the 34 pict-3 carburators were set up for a lean combustion. I have installed a set of duel exhaust racing exhaust. Do you think going to a larger main jet would help? I did a compression check with the engine cold; I got 105, 145, 95 and 60 psi. How bad is that?
Your input is appreciated. Gary
Answer -
im sorry to say that the motor will not idle properly due to the compressions. generally any more than 50psi is difference is a bad sign, and you have one at 145psi and another at 60psi, thats an indication of a serious problem. until the compressions are rectified i feel that altering anything else would be a waste of time. once it is within specification on the compressions, a slightly over bored main jet should help aswell.
Answerright, i will look into the regulator for you as soon as i can. good luck on the engine rebuild. i assume the engine is water cooled, i may be mistaken on that though. if not, the head bolts have a tendency of snapping off as poor design leaves them in the actuall water jacket (so they rot away in the middle) if it is air cooled, you should not have too many problems.
