Originally Posted by Duster_360

NiMh should peak at 125-130F - any hotter and the charge rate is too high and you're shortening the life of the pack by getting it that hot. For a new 3300s, charge at 3.3amps - that should lower temps to proper range, starting out at 5amps is a little high unless you're racing and don't care what kind of cycle like you're going to get - it won't be long starting out that high.

After 5 maybe 10runs, bump the rate to 4amps and see what the temp is like (I use an IR gun on my pacs). If its OK, run them another 5 or 10 times and them bump to 5amp and check temps.