I have a Kanzaki/Hurth KBW10 Transmission, mated to a 2QM20 Yanmar. They are both 35 years old, have ~1800 hrs, and have been babied all their lives (by previous owner and now by me)
About a year ago the transmission started to have trouble shifting into forward first time in the day. It's reproducible at the linkage on the trans body, so I'd think that this is not a linkage adjustment issue.
When it happens, I shift into forward and it does not engage. So far I have been able to resolve it by throttling down, then back up (no need to touch the shift lever). Once engaged, I have no more problems for the rest of the day. there is no noticeable slipping once it engages.
It has never happened in reverse.
It is happening more and more frequently now. Linkage is adjusted, fluid changed regularly (and recently). I use ATF per the label on the trans body (it has had ATF it's whole life). I understand that some folks swear that these transmissions should have 20 or 30W oil. the label says "ATF or SAE 20/30HD".
So I am wondering what are my options. (I do all my own work but I've never rebuilt one of these beasts)
1 - Pull the trans, buy new parts, rebuild it.
2 - Find a used trans
3 - Buy a new one.
In regards to #1, do I need special tools to rebuild it?
In regards to #2 or #3, this transmission is not made anymore, are there recommended "bolt on" newer units?
thanks in advance