Engine Survey: The one day or the 3 day?

[rsmith]

Engines are 8V71TI's that reportedly have 500hrs SMOH. Problem is he has already sea trialed the boat and she only turned up to 2200RPM and ran 215 @WOT and 195 @ a slower cruise. Boat is kept on a lift so its unlikely the bottom or intakes are fouled. Instead of addressing the issues the seller has offered a discount to take the boat as is. That is why I would step cautiously with this one.

Some philosophy injected into the tech. When I was a kid and had the hots for something and thought it was the only deal in the world my dad would say "there is always another trolley car coming down the road there will be another one shortly". I try to keep that in mind everytime I get the oooo gota gave it's.
If your aprehensive, it doesent smell right, got that bad feeling something aint right walk away and look for the next trolley.

[saltshaker]

I think there are a couple of different boats here being confused. There is no evidence (yet) of over heating. These are the in line 6 cylinder 485 HP DD's. Hours are 25 and 200 SOH respectively and about 1500 total on boat.

Oops! Sorry wrong thread/boat. I would do as others have said, do the sea trial first and see how that goes. If the boat performs well and engines hit rated RPM's and run at good temps with no smoke, then you may not need a full engine survey. Keep in mind those 671TIB's are really stressed at that HP rating and as evident from the hours on this boat, 1000-1500 hour failures are pretty common. That doesn't mean they can't give good service life if you run them easy, but most don't.

What model are you looking at a 38, 39 or 41?

[luckydave215]

It can be a tough call, but make your decision based (at least partly) on what engines they are. 485 horse 6-71's? Get the good survey. 310 horse 6-71's? Perform Karl's 30 second compression test. You get my drift.
My boat has 1000 horse (WAY too much for their own good) 12v71ti's with recent rebuilds. The decision was a no brainer, no way I would have bought them without a thorough survey.
The survey on the mains and two gens took two guys three days including sea trial, in this case it was worth every penny. If they were 12-71N's and ran well, I'd have passed on spending the money.

[Boatsb]

Remember someone had 1271n's that ran well until??????

I would want to know the state of the engines and the difference in the cost of the surveys may not be as much as some suspect.

Oil lines, Fuel coolers, Oil coolers and airbox seals could be problematic and need to be checked out. Cylinders and heads will not always tell the story in the short survey. At $25K an engine for a rebuild it makes sense to know the whole story.

On the other hand I can get my 8v53's rebuilt for about $5k if I bring them to the machine shop so there is not a big risk of financial ruin on these.

The engine survey is a way to limit your exposure.

[Pascal]

i think most will agree that an engine survey is pretty much a must, the original question was whether or not a compression test (complicated on a DD) is really needed.

[C. Edmund]

i think most will agree that an engine survey is pretty much a must, the original question was whether or not a compression test (complicated on a DD) is really needed.

That pretty much is the question - compression testing, which would take basically an entire day and be part of the 3-4 day engine survey -- versus the more standard one day engine survey which would go on while the marine survey was going on and the sea trial would simultaneously be part of both surveys.

As for cost, the one day deal is roughly a grand and the three to four day deal would be roughly 3-4 grand. I am beginning to think if the boat performs as it should, the smoke is blue or non existent, and the oil sample is good and the feel, smell, sound test passes muster with trial captain, that the one day engine survey would be the prudent choice. Save the 3 grand extra for future repairs on something. Even the four day bells and whistles test does not guarantee anything.

[REBrueckner]

"...there are also issues with the seller being reluctant to allow an unknown mechanic doing compression checks on DD....

If the seller is fussy and is reluctant to have a stranger take apart his engines, I can understand. What happens if they don't run to the current owner's satisfaction after the survey?? Who is responsible?

[saltshaker]

That pretty much is the question - compression testing, which would take basically an entire day and be part of the 3-4 day engine survey -- versus the more standard one day engine survey which would go on while the marine survey was going on and the sea trial would simultaneously be part of both surveys.

As for cost, the one day deal is roughly a grand and the three to four day deal would be roughly 3-4 grand. I am beginning to think if the boat performs as it should, the smoke is blue or non existent, and the oil sample is good and the feel, smell, sound test passes muster with trial captain, that the one day engine survey would be the prudent choice. Save the 3 grand extra for future repairs on something. Even the four day bells and whistles test does not guarantee anything.

Sound like good reasoning although blue smoke would not be good. You don't want to see any significant smoke except for a slight puff at a cold start that should clear within seconds.

[Genesis]

I would not allow a compression to be done by a BUYER'S mechanic. I would permit one to be done by MY mechanic with the seller paying ME (and me paying the mechanic, and him being hired by me), but that's probably not going to go over well with the buyer.

Boroscope and other inspection-style things, sure. Little or no risk there as the stuff under the valve cover is not touched. Inspect all you want.

Who's responsible if the mechanic improperly torques a bridge bolt, the buyer backs out of the deal (for any reason, including one unrelated to the boat's condition) and it backs out or snaps, wiping out a cylinder six months later? No thank you.

Now if the inspection discloses questionable (or worse) conditions, then you have the seller in the corner - the deal is probably blown at that point, but you can always make it simple for him: a price adjustment allowing for a full overhaul of the questionable engine(s) or you walk.

[lumina]

Hi All, (posted this on another thread also, it seemed to apply to both)

I was fortunate when I started looking for my Hatt because I already knew what I wanted, which was the Hatt of my childhood which I spent many wonderful summers on.

I was looking for a 1974 48 Yachtfish, the 3 stateroom model with 8v71 naturals.

It took a while but like Rob when I saw mine I went “ooooo I gotta have it”. So far so good, knock on teak.

Having investigated many other models just to be sure I always came back to the Yachtfish, it's versatility and roomy blend of motor yacht and cockpit fisher.

I urge anyone looking for a comfortable cruiser to take a look at the yachtfish.

As far as surveys go I had a structural done as well as an engine & mechanical. It didn't include a compression test. I was tempted since one engine had 1800hrs and the other had 3600hrs. The owner could not provide an explanation other than when he bought the boat the engine hours had the same relative discrepancy.

However, both engines started right up cold, the stbd engine ran super clean and super smooth and fine at top rpm. The port engine (3600hr) smoked whiteish smoke at startup for 3-5 minutes then ran super clean and super smooth and fine at top rpm.

I took the chance and had the boat bought to Massachusetts from Floridia.
No problems, ran like a top.

Upon arriving in Mass I had the port engine tuned and that removed the smoke. The mechanic told me the rack was to tight and the injectors were set incorrectly.

So again so far so good, knock on teak.