NSW
608 posts
Hi groovers. Ex-lurker here. My first post. Howdy and thanks for all the great advice I've gleaned over the last 12 months.
I've been looking for a while now at getting an old yacht under 30 foot. I looked at one the other day which was mostly fine except that when motoring the 8hp Yanmar smoked a bit in cabin. You wouldn't want to sit in there under power (which i obviously wouldnt do but the missus might under certain conditions). It's the original, which makes it about 35 years old.
I'm not particularly mechanically knowledgeable so I'd love some advice on this. How common is this? I've not seen this before but then my experience is limited. I suppose it could be a number of things and I'm not sure I can give much more info.
I'm trying to work out whether this is avoidable and also how much I'd be risking a costly / inconvenient / dangerous problem.
Cheers.
NSW
7757 posts
The Yanmar you describe sounds like the single with the horizontal piston, ysm 8 or something similar to that. These were probably reasonable motors 30 years ago but they suffer ring wear and blow back. Parts are a problem although whole motors appear on eBay occasionally. I would avoid them personally and did so when I was shopping for a "new " yacht a few years back.
NSW
2711 posts
Agree with Ramona. It also could be exhaust leaking into the boat, if so very dangerous.
Price a new engine, including installation/shaft/prop, and use it to get the price of the boat right down.
NSW
7757 posts
I think you will find the answer given to the question was absolutely correct.
I would expect probably a Volvo md7b in a 30 foot yacht around the 17 grand mark.
VIC
664 posts
It could also be a small diesel leak. I once had this problem with a pin-hole leak in the flex hose to the injector pump - a little bit of fuel on the warm head and exhaust elbow was enough to cause minor smoking. If this were the case, you'd also probably have the diesel stink to go with it, although with an engine that old there could be all sorts of other sources of that lovely aroma. Work-hardened copper washers under the fuel line banjo's are also a leak source - put new ones on if you disconnect any hoses or if you have the stink.
I've also had steam (that I thought at first was smoke) from a loose engine anode weeping onto the ehaust.
lockie
