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Sun Feb 21, 2010 5:32 pm

When i am in mostly 2nd gear and higher, there is a pretty loud high pitched whistle sound when i get into high rpms. if i let the rpms come down, the sound goes away... Any idea as to what this may be?
i checked the belt to see if there was slipping, but it seems to be good...

Sun Feb 21, 2010 5:37 pm

what do you know about the engine?
it always been there?
maybe you got a straight cut cam gear.

Sun Feb 21, 2010 5:39 pm

I had a whistling noise at higher rpms just after I changed my clutch... it went away a few weeks later. Done any work on the bus recently?

Sun Feb 21, 2010 5:39 pm

does the whistle go away when you take your foot off the gas a little and get worse when you put more gas to it? Or does it get louder when you lift off the gas a little? Does the texture of the road change the sound?

Sun Feb 21, 2010 5:43 pm

i installed a 1600 single port about 2500 miles ago. i also replaced the clutch a the same time... The noise started a bit ago...i expected it to go away ...but its still there and worse now.. after i changed the oil, adjusted the valves and tighted up the belt. The engine is running great and strongest as ever....just a high pitched noise (whistle) when i get into high rpms. when the whistle starts, it will get worse if i give it more gas...i havent tried to find how loud, or long it will go for, im scared of fire. but if i let go of the gas...wait for the rpms to come down...i can usually cruise at the same speed or faster with no noise... (road surface has nothing to do with it)

Sun Feb 21, 2010 5:57 pm

Have you put a dusting of Bosch distributor grease on the points rubbing block?

Sun Feb 21, 2010 6:03 pm

nope, i havent...should i ? and can you explain the process if i should...please

Sun Feb 21, 2010 6:12 pm

Usually that is more of a "chirping noise", but give it a shot since you need to do it anyway.

http://www.thesamba.com/vw/forum/viewtopic.php?t=259777&highlight=distributor+grease

Sun Feb 21, 2010 6:32 pm

Air intake leak??

Sun Feb 21, 2010 6:32 pm

You need to determine if it is engine noise or trans noise.
If it's trans noise it would be related to which gear you are in, or the road speed, or if it is under load or not, or all three of those factors combined. If it is engine related it would have to do with engine rpm's. And probably not relating to gears, vehicle speed or even stationary and in neutral. If it's engine related remove the belt and try it. Not for longer than a minute though.

Sun Feb 21, 2010 7:06 pm

If you rev the motor is it there or do you have to be moving?

What kind of air cleaner are you using?

Sun Feb 21, 2010 10:05 pm

if i just rev the motor in neutral it doesnt happen. it happens only when im driving in gear and in high rpm.

im using a K&n air filter.

im starting to think its a tranny problem...

Sun Feb 21, 2010 10:46 pm

when is the last time you checked / changed your trans oil? Richard Long told me about 150K is how long VW bus trans like to live before going downhill. He said the pinion bearing is usually the first to go and that can wipe out the ring and pinion. You can try a heavier gear lube like a 120 and it it quiets it down then you will know it is the trans. If it isn't then put 80/90 back in it.

However air cleaners sometimes whistle so that can be it too. Trans whine and air cleaners whistle. Listen closely.

Sun Feb 21, 2010 10:53 pm

im afraid you gave me the word i was looking for in trying to describe this problem. its a high pitched whine.

Sun Feb 21, 2010 11:00 pm

if you can change the strength of the high pitched whine by easing off the throttle just a little then it is likely the pinion gear or bearing. You may even be able to feel it in the shifter.

Do check your trans fluid level and change it if it is more than a few years old. You can try a heavier gear oil and see if that quiets it a little but it won't last.

Mon Feb 22, 2010 12:19 am

You might get one of the trans builder pro's to test drive it for his evaluation. They should immediatly be able to tell you what's making the noise. You're in a good location for that. It's not as if you're in the middle of Kansas with a lack of VW trans builders. Different components and different bearings in a trans make different kinds of noises. Mine has two different unrelated noises and is going to get rebuilt real soon.

Tue Feb 23, 2010 9:51 am

i found out the whistle is coming from the generator/fan. i disconnected the belt and ran the engine for less than a minute .... and no whistle/whine. how should i go about solving this problem now. the generator was recently installed about 2500 miles ago. it was rebuilt professionaly by a local shop. im going to try to take it there when i find time. but anything i can look into in the mean time?

Tue Feb 23, 2010 10:56 am

Good news that it isn't something deep in the engine.
While the belt is off give the generator a spin and listen, rub-rub-rub-rub somewhere?, fingernail on chalkboard squeek?, faint chirp? Does it change if you push in or pull out on the pulley while turning it? Does it change if you push/pull on the top of the fan shroud? Have a look at the fan and where it's edge meets the inlet hole in the shroud with a mirror and light too.

Tue Feb 23, 2010 12:34 pm

Here are a couple ideas. Do each one and test to see which it is.

If this is a generator, with the engine off use a dry wooden or plastic dowell to push against each of the brushes, it could be they are squeaking. See if that changes the character of the squeak.

With the engine off and the key out, reach around behind the fan shroud and see if a piece of plastic or rubber etc has been pulled into the fan and is rubbing on the fan blades.

With the engine off and the key out wipe the belt with some alcohol or carb spray on a towell. Use some really light sandpaper to scuff the area of the pulley where the belt rides. Clean it too with alcohol or carb spray on that rag. Does that change the nature of the squeak.

Tue Feb 23, 2010 1:28 pm

SGKent wrote: when is the last time you checked / changed your trans oil? Richard Long told me about 150K is how long VW bus trans like to live before going downhill. He said the pinion bearing is usually the first to go and that can wipe out the ring and pinion. You can try a heavier gear lube like a 120 and it it quiets it down then you will know it is the trans. If it isn't then put 80/90 back in it.

However air cleaners sometimes whistle so that can be it too. Trans whine and air cleaners whistle. Listen closely.
The main bearing always beats the pin bearing to the going bad stage. but thay are not too far from each other. thay always both get change in a overhaul. At least anybody that does a good overhaul. I have never heard a trany whistle but thay do a whirring sound. One thing to check when the engines out is pull on the input shaft. if you can pull it in and out and it moves then its time to be looking at the trany the main bearing is floating it will be poping out of 4th soon. not side to side thay all move alot that way.