Sound changed?? New belts and hoses

[Pit Bull]

Changed belts and hoses on the wifes 95 Toyota Landcruiser and it now sounds different. Trucks has over 120K miles on it. Do new belts change the pitch of the motor sound. The belts are not slipping and are adjusted correctly. Might of gotten a little antifreeze on them? Driven it 20 miles since the change and it is now quieter but still sounds different? Kind of a whistle?? Local friend mechanic said it did sound different but not bad, like something was wrong. Just curious if anyone else has noticed a sound change when they went to new belts? (these were Gates belts).



Thanks for your comments

 

[LSMITH]

I have had anti-freeze make a rubbing sound when I got it on the belts, almost a sqeak but a constant sound. To find out if that is what it is take a glass of water and pour it on the belts as the engine is running and see if the sound changes or goes away. Wear safety glasses, water WILL fly everywhere. For me a couple glasses took all the ant-freeze off and the noise was gone for good.

 

[Pit Bull]

Thanks for the idea. I went even further and washer the engine with cleaner and water. Making sure that I got the new belts real good. They sounded a little better. But here is the big thing I notice about this noise change. It is louder when the engine is first started. It gets a lot quieter after the engine has been running for a few minutes and there are some RPM's that it makes no noise at all. Kinda gets louder and then quits making noise at around 1800 plus RPM's. Weird. Any guesses? Could it just be new belts? I checked and no wobble from the alternator or the fan and the water pump is dry.