Finally got back on the mower after some bad weather. Went up the same slopes with diff lock off and there was no squealing. Put diff lock back on and again went up the same slopes; no squealing.
Went and had another look under the seat and noticed a retainer on one of the clutch linkage bar pivot points was missing.It did not seem to cause any problem to the operation of the clutch forks but I went down the dealership to get a replacement.
Advised one of the mechanics about my problem and he was very confident the noise was coming from a slightly loose drive belt.
I knew that the manual stated that the drive belt was self tightening and that when I had inspected it, all seemed ok.
He explained that the belt is normally self tightening but sometimes it gets slightly loose and a 1mm adjustment would fix it.
He told me to just get a metal bar and lever the mechanism that tensions the pully in front of the clutches just a little forward until you here it click into the next notch . No need to remove or untighten anything.
Well I did what he suggested and it worked like a treat, putting just a little more tension on that large spring and moving the pulley out just a little.
Now I'll tell you if it's a permanent fix after a few days of use but it's certainly looking positive.
Regarding some of the earlier comments in posts from members: The mechanic said he has rarely saw a worn clutch facing, even on commercially operated machines, before ten years use. This is a large Greenfield dealership and always have about 20 in the yard when I visit.
He said that the shaft may need oiling before the clutch facings wear out.
Anyway it's operating like new again, punching up those hills without missing a beat and cutting through the thick stuff like a hot knife through butter. And that's why I bought it along with the 45 year old reputation.
