Yamaha TRP Sterndrive, Yamaha Sterndrive, Yamaha me420sti , Yamaha diesel, me421sti, Hydra Drive
M.V.Diveworks (10.1 meters, 4 tonnes) was fitted with a new Yamaha ME420 sti Trp diesel sterndrive unit in December 1997. I opted for a Yamaha at this time rather than the more popular New Zealand option of a Volvo penta or Mercruiser due to Yamaha's reputation. (Unfortunately though, unlike Volvo, Yamaha offer no warranties for Commercial use)
With trouble free operation for the first 1500 hours my first ever breakdown was due to a failed outdrive. Replacement with a new outdrive gave me an opportunity to disect and become familiar with the old drive. Since that date I have done all repairs and maintenace myself. Im often asked why I dont operate lower maintenance shaft drive or jet due to the considerable time I spend on the water but I think the advantages of being able to maintain and repair myself, plus being easily surveyable, with excellent manouverability, shallow water operation, trailerability and a minimal boat downtime by having a spare drives and engine ready to go, outweighs most of the dissadvantages for me.
As at May 2009 and 6000 hours mostly high speed use, I have completed 4 engine rebuilds, 3 intermediate housing rebuilds and countless stern drive rebuilds for myself and others.
If you have one of these units and wish to know more, the repairs and maintenance of, then click any of the above Sterndrive pictures to be taken to another page.
I am happy recieve emails from all corners of the globe both seeking and being given advice and assistance with these drives.
Feel free to contact me on tips and hints on the operation of this unit
Phil van Dusschoten
(You are welcome to contact me via Mobile 027 628 0849 or 64 07 308 5896 but please do not use our freephone for engine Enquiries, I dont mind giving free advice but it does hurt a bit when I get a hefty Freephone bill as well. Many Thanks)