constant whistle noise (1 Viewer)

[weatherm]

I have gotten everything fixed so far on the truck but there is one out of two noises that is really aggrevating me. One I think is the idler pulley because it has that screaching at idle and take off but good after that (correct me if I'm wrong) and the other is this misterious whistle noise. It sounds like someone blowing a whistle and it doesn't change w/ rpms acceleration or anything. If you choke the engine out it dies with the engine. We checked all the hoses for leaks and listened with a screw driver. It is NOT the brake booster but is coming from around that area so we think. We made sure the exhaust manifold was on good and tight. The resident cruiser guru things its something to do with the exhaust or the carb. I have a 2 barrel webber carb.

Thanks!

 

[dgangle]

there is no way anyone on the otherside of a computer miles away from you can pinpoint the cause based upon the info you have provided. You are going to have to isolate it yourself, or with the help of someone that can assist you in person.

If the whistle goes away when the engine is turned off,......well, that pretty much isolates your problem right there. My guess is a bad brake booster or other source of ported vacuum. Start there and good luck

 

[weatherm]

We unplugged the brake booster and it was still there and also checked the line going to it so its not that. Its a vacuum leak somewhere. We think its the carb so maybe some has had a similar issue.

 

[MoCoNative]

When I ran a Holley with an open filter air cleaner, like most aftermarket carbs have, it produced a constant whistle sound. Not very high pitched, but it was always there. But it would change pitch some as you accelerated. That is why factory air cleaners on any vehicle have all the ductwork and crap, so you can't hear the air being sucked in. Did you check the PCV line, the seat of the air cleaner. A vacum leak after the carb will affect idle usually. So it is probably above the carb, or not affect performance.

 

[weatherm]

Idle is good... and we did check the pcv line and the valve.. all is good there. This has to be something silly.

 

[VTGreg]

I had a Weber on my rig for a while and had a whistle that would vary with throttle. The bolts that hold the manifold adapter plates together, as well as the carb mounting studs themselves, were just a bit too long and when everything was tightened down the joints would spread. Take all the pieces off your manifold, bolt them together, and have a look to see if the ends of any bolts/studs are protruding at all.

 

[weatherm]

Fixed. Bent alternator mount arm (the one you adjust the alternator with) It was off a few degree.. I whipped out the trust rubber mallet and no more noise! Time to find a replacement

 

[AATLAS1X]

I had the same thing last week and a quick text message to POSER and the reply was telling me to tap the EGR and sure enough it worked. I then put some snap-on tool in it and used a hand vacuum tool to open and close it and not a problem sense.

Shane

 

[AATLAS1X]

EGR # 7 Specter Off-Road Land Cruiser Parts - Page 047 EGR Components

 

[AATLAS1X]

only pic I can find of a hand pump http://www.dootalk.com/forums/uploads/1169343898/med_gallery_1528_578_23508.jpg

 

[weatherm]

nice thanks!

 

[fjatheart]

My whistle came from a pin hole sized air leak around the WEBER adaptor plates. I temporarily sealed it with liquid gasket then later eliminated the adaptor plates for the one piece plate that MAF sells.

Once air leak was gone I saw an increase in performance.