Gary, very true!
I will occasionally still see some of the older 250's thru 290's that still operate perfectly, and some of these have never been touched.
Worst case we replace:
Main drive gear bearings after 20 to 25 years of service! (mostly with the V-8 transmissions)
PDS bearings after 20 years of service whereby the engine must be removed.
PDS bearing after 20 years of service whereby the engine does not need to be removed.
I do see drive damage due to the owner not doing a routine re-seal and/or routine drive shaft bellows replacement.
These are not drive design flaws. These are caused from owner stupidity.
BTW, Volvo Penta's first Cone Clutch out drive came out in the late 50's. Not many changes to the basic design have been made since.
BTW #2..... Volvo Penta's Duo Prop drive was introduced in 1983. And again, not many changes to the basic design have been made since.
The major draw back with the very early drives, was not offering a decent PT system.
The 250, 270, 275, 280, 285 did not offer anything but the Lift Out unit.
The T drive was all but a disaster.
The PT drive was just barely OK, but it lived a short life on the market.
The 290 drive had that awful anchorage bracket system and still required the break-a-way feature refered to as the Reverse Latch.
When the C and later drive was introduced.... things get much better.
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