There is a metal tinging sound coming form behind the fan. Almost sounds like there is a nut or bolt stuck in the fan, just guessing though. I don;t know much about VW engines and could sure use any thought you all have on my issue
Thanks
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I had paper towel get sucked in one once. Only caused engine to run hot though - so something stuck in there is possible. With engine off (duh)- have you reached in from back to check for debris The fan can be removed without removing complete engine or shroud. Fans can crack around the 36 mm mounting bolt due to being off balance at high revs or the nut can loosen. You can get replacement high performance welded and balanced fans. If the fan itself is ok and no debris - it could be hitting the shroud slightly. Check to see if shroud is loose if not then the fan can be removed and the shims adjusted for clearance.
I can send my mechanic by! (Posted here ages ago)
Sometimes these after market alternator pulleys crack and make noise. I would remove the fan belt and start the engine. If the noise goes away then it could be the alternator or fan or pulley (rotate the alternator by hand and see if it makes any noise), if the noise is still there look for something rubbing on the front pulley at the base of the tin or if could be internal. Also if may be the throw out bearing. Push the clutch in to see if the noise changes.
Good Luck
Sassy,
Any progress trouble shooting the metal tinging sound? After a long ride Saturday I started getting a similar sound but haven't spent time tracking it down yet - just listening on the street it was difficult to tell if it is under the engine or not.
Quick and easy thing to check, if you have dual carb's juggle the intake/air cleaner and see if one moves more than the other. I had one shake loose. Car ran better after tightened too. It sounded like a chirp kind of.
I took the 356 in to a mechanic because I was having issues with setting up my carburators, so I figured what the heck, just let the mechanic do the noise issue. I will let you all know as soon as I get it back what it was that was causing this noise. Much Thanks for all you support, shall be in touch soon.
A ha! Now there's some information that may help diagnose problem. Engine knock or "Pinging" is the metallic rattling sound an engine can make when accelerating. It's cause by running lean, spark timing and/or high compression (could be from carbon build up). This pre-detonation can make your engine run hot and even burn a hole in a piston. Modern cars are computer managed and don't have this rattling problem (reason you can run lower octane gas in a car designed for premium without it knocking).
https://www.youtube.com/watch?v=OGCcTw3j0fY
It's not pinging Greg, at least not on mine. When you rev the engine it's a tinny, rattling sound.
If it sounds like a bunch of marbles rattling around in a coffee can, that is the sound of an air-cooled engine pinging. Of course, that would be when under load, not just revving it up no load.
Another thing to check, have the spot welds holding the tabs on the tins to your heat exchangers broken off (if you have them). Mine did and sat close to the H.E.'s which caused a rattle.
It was the fan. It had a small hair line crack in the fan.
Sorry for the delay
Thank you for the advice, simply makes this site the best !!!
Thanks for the update, time to tear into mine.
I just went through the same thing. Pulling the motor apart today as it's internal...
Also replaced the generator as they felt its bearing was making noise also
Well, my fix was muuuch easier. I tried revving the engine by myself but could not get to where I could hear the source of the tinging sound. Finally asked my wife to get in the car and rev the engine while I hunted around for the sound. After several revs I found the noise...the screw that holds the muffler inside my stinger had come loose and the muffler was moving out a bit and rattling. A quick tightening with a Phillips screwdriver and problem fixed. Phew, that was easy and a big relief!
Found my flywheel wobbling (still torqued down) and the dowel holes elongated. Put a new one on and something else let go. Time to pull it all apart...
Older german vw guy saw a motor I had out due to elongated dowel pin holes....drilled each hole out with a larger diameter
bit, cut the bit short using them as larger dowel pins.
Alan's cure is the accepted one if you wish to save both the crankshaft and flywheel. Find a really decent automotive machine shop and they should be able to handle it.
Or you can do what I did on a 36 hp engine in my first dune buggy: I was in high school and had no money and the flywheel had loosened three times in two weeks, even after being torqued to well over 400 ft. lbs.
I just torqued up the gland nut (again) and then welded two opposite flats of the nut right to the flywheel. That engine ended up in someone else's VW sedan when I went to a bigger engine and it ran for several more years.
What is the cause of the elongating holes if the gland nut was torqued properly?
Sounds like the Gland Bolt / nut bottomed out before proper clamping pressure was applied to the flywheel.... I've only seen this apparent problem once, after a flywheel had been refaced and the grinder refaced the crank shaft mating area also...
Did builder forget the gland nut wavy washer? If it only has 4 dowel holes - get it drilled for 8. Most lightened replacement ones are 8 dowel.
Nope. 8 dowel
If the dowell holes are loose in either the crankshaft or flywheel your best to start over. Some machine shops over the years would install larger dowels but then you end up with a custom one off set up.
Most likely the gland nut came loose, or if the dowels were changed for different size it was not a tight fit.
the other issue could be cheap parts. Don't use any aftermarket empi or off brand gland nut and flywheel. The old factory stuff works fine in 80% of the applications. I have broken gland nuts when trying to torque them to specs. Several aftermarket flywheels are junk, soft and they flex.
if you have a good machine shop that knows vws this usually isn't a issue, but be aware and ask questions!
