Perkins 4-108/Westerbeke 40 What Weight Oil?

[jpendoley]

Hi Folks,
Am just getting to launching my 365 (long galley rebuild) and I am thinking about my leaking rear seal-it leaks a lot. Would changing to a heavier weight oil make sense?  I was thinking of going to straight 30. Thoughts?

[Della and Dave]

It may be a forlorn hope, but the Westerbeke manual says that if you are getting a leak at the rear seal (front to us) and a bad seal is suspected, check the breather.  It may not be the problem, but if it is, it saves you a lot of pain.

I have tried thicker oil in other worn out engines, not in boats and not diesels, , and in my experience, it didn't help much.  At best it slowed it down just a little bit and that may have just been wishful thinking. 

[jpendoley]

-its a pretty crude mushroom cap with a screen-what should I look for?