35 year old 671's - can they still be good?

[moveover]

I'm considering a 75 38' Egg sportfisher with original 671's with 700 hours. I know nothing about diesel engines and I guess I should have an engine survey but are there any tips anyone can give me about evaluating this deal? The asking price is 10K which seems good. also Has an diesel Onan gen with similar hours. The house is wood which of course can be a big problem but the pictures and the owner say the wood is in great condition. Leaking windows are a known problem with this vessel and I'll check that out.
The reason for the low hours (according to the seller's story) is that the original owner used it only 20 hours a year then put it in dry dock for about 7 years. the current owner bought it 2 years ago , changed all hoses etc and used it as a fishing boat, for hire, from Long Island out to the Canyon about a dozen times.
thanks for any tips you can give me.

[clt_capt]

I can't really speak to the engines - I can't really imagine them being all that great just sitting around

I'm a bit more familiar with the boat - my former dock mate had one - He had some major rot issues with the covering boards - apparently the rod holders weren't properly sealed when installed.

He also had major blistering issues with the hull.

$10K isn't a lot for the boat, if you are willing to put the effort in to fix the things that need fixing - Just make sure you go in with your eyes open

[54bullwinkle]

If the boat has been running last 2 years, I wouln't be afraid of it. He probably has de-bugged all the things that are likely to go bad after 5 years in the yard. dry hoses, impellers, light bulbs from corrosion, cables rust, etc.

They are prob 6-71N (natural, non turbo)in that vintage boat. They have several thousand hours of good service left if they are ok now.
Need a compression test. Problem with sitting is that the cylinders will get rust spots and will lose some compression.

Start them cold......They will blow blue smoke (they all do)
they should barely smoke after they reach 150F. If they are still throwing blue smoke, compression tests needed.

[moveover]

Thanks very much guys. That's exactly the kind of specific information i was looking for.

[54bullwinkle]

Those old Eggs had some beautiful Mahogany interiors. Some really nice wood finishes. Interior helms with a classic look.
Cockpits were small and had no boxes.

Good luck with it

[aj1976]

yes, 35 yr old 671 dds can still be good. I have a 41 ft 1981 sportfisher w/ twin 671ti's -- still running w/ over 6000 hours on each engine. Like someone already stated above: if they were running in the last 2 years = maybe still good. the problem is if the engine does not run you get problems no matter how low hours. Our engines have been used regularly for the last 20 years (for the most part). When they sit for more than a few months we get problems -- nothing that can't be fixed. everything is still original.

[moveover]

I'm supposed to see the boat today or this weekend. I have a feeling the big issue may be the condition of all the wood even more than the engines.
I dont mind doing alot of dumb labor like sanding and varnishing, because these kinds of classic boats are kinda works of art, to some extent. I admire beauty over efficiency, in other words.
But if there are major structural wood issues, like with the house or glass covered stringwers - forget it - thatas over my head.

[JD5652]

671's have been around a long time and will be around for another 20 years.

One other simple thing you can do and remove one of the air box inspection covers and bar the engine over manually to inspect a piston (or pistons) and the cylinder wall (sleeve). You want to make sure that the original hone marks and cross hatching is on the cylinder walls and tops of the pistons are dry (meaning no oil). This will give you an initial indication of the engine health.