Being crazy about Yanmar and ZT370 drives we came up for a stunning SS lower drive upgrade for OEM part #196350-02611.
Bearing cradle is hiding under the propeller. You will not see the problem, unless you remove FWD propeller, and that does not happen often. Sometimes only once per navigational season the FWD prop is being removed. Due to the fact we have oil seal in the front end of a bearing cradle, fighting with corrosion is limited, until corrosion slides under the oil seal. Then it is just a matter of short time, when we have water in stern drive, and costly OH to follow. In order to monitor the issue, the boat has to be lifted, prop removed and inspection carried out. This process is costly alone and can be anywhere between 200 and 600 Euro, depending on marine service charges and size of a boat to lift, just for inspection. We had such issue on one of the boats and started to think of a possible solution.
From the drawing board
For the boaters that are tired for repeated Yanmar ZT370 corrosion issue on lower gear bearing cradle, we have solution – SS upgrade. Costly but surely it will solve the issue, however, that is much cheaper than complete OH of stern drive. Manufactured from AISI316 grade SS bilets. Manufacturing is done by combining CNC and EDM machining technoligies. Final assembly done from 2 individual sub-parts, using thermal expansion and subsequent shrinking process, using sealant in addition.
Description of design & manufacturing assembly process in our video:
Yanmar ZT370 lower gear bearing carriage in stainless steel – best answer to corrosion resistanvce
Innovative manufacturing using CNC machining and 3D printing opened new horizons in manufacturing complex parts. Unachievable in 20th century is done deal today. The 5-axis machining performances allow the production of various complex parts in more convenient manner