Old Yam 115 2t: Replace the oil pump ?

[axolotl]

Hello.
2 years ago I bought a mod. 1991 Yam 115 2T. The last owner had it rebuilt twice for reasons he did not clarify.
The engine has already 37 hours of flawless operation in my hands.
However, for "peace of mind" reasons, I am planning on installing a new oil pump. It is already 20 years old, and maybe its a good 150 bucks investment, securing or maybe lengthening the future of my outboard.
What do you think ? Should I proceed with this move?
In this case, is it worth installing the 130hp oil pump, which has an increased oil volume output ? According to the manual, the 115 oil pump pumps 2,9-3,5cc per cylinder @ 1500 rpms, while the 130 oil pump goes up to 4,3-5,3cc per cylinder.

 

[robert graham]

Re: Old Yam 115 2t: Replace the oil pump ?

I've never heard of anybody just routinely replacing the oil pump, but it may make you feel better if it's on your mind. Maybe one of the experts here will have some ideas how long the oil pumps can last, and if replacement is required or recommended. Usually folks are talking about removing the oil pumps and going to premix for dependability. If previous owner had powerhead rebuilt twice, maybe because of trash in carbs/jets/lean fuel mixture more likely than oil pump failure. Whatever you do, install a fuel/water separator type filter on the transom, save yourself a lot of fuel related problems. Good Luck

 

[99yam40]

Re: Old Yam 115 2t: Replace the oil pump ?

I would think doing the recommended preventative maintenance on the oiling system like draining ,cleaning, and measuring the output would even be a better idea for how the system is functioning.

I think putting parts in a motor that they were not designed for it is very bad idea.
but that is just my thoughts

 

[axolotl]

Re: Old Yam 115 2t: Replace the oil pump ?

Hmm. Thanks to both of you.
As Robert mentioned, dependability is my issue here. So any marine mechanic with experience on oil pump failures ? Does it just happen randomly, does it become more probable with oil pump aging, with hours of pump operation ? Or am I on a wild goose chase here ?

 

[99yam40]

Re: Old Yam 115 2t: Replace the oil pump ?

From what I have read the problems are not with the pumps failing, it is the sludge build up in the tanks, filter & check valves plugging and oil lines breaking, that keeps the oil from getting to where it needs to be. With proper preventive maintenance they will work fine for years and years.

But maybe some of the Yamaha techs will respond to your request for info.