engine belts

[Crowbar]

1987 28ft voyager w/ twin 230 mercruisers I've replaced belts 50 hrs ago now they squel on startup for 2-3 minutes using napa gates belts. Also increasing load quickly makes them chirp. they seam too skinny for the pulleys. how would I find the correct belts and are there better belts available? Bothe engines do it but port is the worst.

[waybomb]

You should find the right part numbers in a mercruiser parts book.
NAPA Hats are fine.

[Viper]

Try Mercruiser original belts and make sure they are set to the correct tension. Aftermarket parts don't always cross to the exact same spec. Click on this link and enter the engine serial number, then look for the belts, probably in the alternator or circ pump page and the sea water pump page....
https://public-mercurymarine.sysonline.com/Default.aspx?sysname=NorthAmerica&company=Guest&NA_KEY=NA_KEY_VALUE&langIF=eng&langDB=eng

[bud37]

Source of the post I've replaced belts 50 hrs ago

Did you readjust the new belts after a few hours or were they just fine the whole time until recently. New belts could need to be checked after a short time after install to make sure tension is right. It is possible they were a bit loose and the edges wore away till they started to slip and squeal on load.

Make double sure the pulleys are lined up as well. Napa gates stuff is fine, the old belts could still have the id / size on them but need to be the right length to get tension correct.

Watch out for metric sizing., proper fit in pulleys is important.