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74 beetle acceleration problem - engine detective needed!!

Help! I am looking for any suggestions of how to resolve what is happening, and ideas on what else to check My mechanic has serviced my car for 17 years and I have never had any car problem he hasn?t fixed on the first try, until now. The engine is a 5-year-old rebuilt (which he did), the carburetor is a rebuilt (4 years old), clutch and trans just put in back in April. Car is serviced regularly for oil changes, tune-ups, etc.

Recent history: In April 2004 - clutch and transmission installed. No problems. One week later ? battery died. Replaced it. Within the next few weeks, the engine developed severe acceleration problems ? hesitation, sputtering, chugging in every gear, accompanied by heavy exhaust fumes, and the car started going through way too much gas. I brought the car to my mechanic 4 separate times and here is a list of what was found and completed:

  1. Engine was only running on three cylinders, and one cylinder head was cracked. Replaced both cylinder heads. No change in performance ? brought it back.
  2. Fuel pump replaced, carburetor was cleaned, adjusted, etc. No change, brought it back. Timing, points, electrical all tested fine.
  3. Vacuum advance unit had a hole in one side. Replaced vacuum advance unit. The heavy gas usage was resolved, but no change in acceleration, brought it back.
  4. Timing adjusted. Engine worked okay for two days, then over the next week deteriorated back to the same acceleration problems and exhaust fumes. The car had a rough start (the engine made two big knocking sounds), and a little while later while in second gear the oil light came on for about five seconds, then faded. Brought the car back and my mechanic is checking it out again.

He has tried everything he can think of and obviously has had no luck. He has checked the carburetor, even taken it apart, adjusted valves, checked the spark plugs, adjusted valves, etc. (all the things you are supposed to do for acceleration/hesitation problems. I want to give him some suggestions on what else to check. Any suggestions/ideas are greatly appreciated!

Thank you!!!!

Reply to
cutee2525
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Carburator needle valve leaking, thus flooding the carb or overfilling it

Jan

Reply to
Jan

"Engine worked okay for two days, then over the next week deteriorated back to the same acceleration problems..."

I think that's the salient clue. It says there's nothing major wrong with the engine itself.

What could deteriorate (slowly?) over a week or so? I would focus on the distrib to begin with (it's easy anyway). Is the point gap slowly closing? Is the vac advance getting weaker? Check the advance against the specs.

A compression test might be worthwhile, if for nothing more than peace of mind.

If all that checks, look at the carb, especially the float and needle valve and the accel pump dischg.

Speedy Jim

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Reply to
Speedy Jim

Try a known working ign. coil and maybe spark plug wires.

Was a leak down or compression test done? What type of air filter are you running and is it clean and free of obstructions? What does the motor oil smell like? Might be a ruptured fuel pump which may be leaking fuel into the crankcase causing your heavy gas usage then thinning out the oil causing the oil light to come on then causing the engine to run poorly due to too much thin oil in the crankcase! Whew that was one LONG sentence! lol

good luck and let us know what is discovered.

later, dave Reminder........ Before you criticize someone, you should walk a mile in their shoes. That way, when you criticize them, you are a mile away from them, and you have their shoes. Frieda Norris

Reply to
dave

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