What to look for?

I would look at:
- Engine temperature during rpm range
- Maximum engine RPM on both motors
- Speed during RPM range (app on your cell?)
- Engine smoke (what color and at what time and rpm)
- Oil pressure during RPM range
- How does de gearbox functions (delay? Strange noises?)
- Gearbox pressure during RPM range
- Controles working smooth?
- How’s the steering working?
- Trim tabs are working?
- Check for leaks in the engine room, after sea trail (take flashlight with you)

Keep us posted with your figures and we also like pictures!!

Fuel tanks! Make sure that they look good and aren't leaking.

I would ask how often did he change the oil and filters, and does he have any maintenance records, of work done.

In addition to everything above, walk the entire boat barefoot, see if there are any soft spots anywhere on the bridge deck, the covering boards, cockpit, and foredeck......

If you have a survey also, check under floors, look at the toilet system, leaking water tanks and windows!

P46 is right on the mark.

I recommend that you do not use a surveyor that is recommended by the owner, broker, or yard. It can be a conflict of interest.

I have had very good luck using Boat US surveyor referral service.

Also, it is worth the cost of hiring a separate engine surveyor, a Detroit Diesel Expert.

Good luck, if you do purchase the Post, I am sure you will not be unhappy.
I don't know anybody that has a Post that is not happy with the boat.
My Post has exceeded my expectations of the boat.

Well, the survey has been completed. We got 26.7 knots at @ 2600 RPMs. Both engines ran hot. Came back to normal on reduced power. Wondering if it is heat exchangers or something else. I did not see if the coolant level was checked prior to start up

Was the heat read from a pyro meter or the gauge?? I would think the heat exchangers could be a main culprit, but some other factors could contribute.

I would check intake water flow first at the seacock or sea strainer, then check raw water impellors/pumos before tearing apart exchangers.....HOWEVER get yourself one of those little camera's and pull a sea-water hose in stick the camera up in there and inspect them before pulling everything apart.....a lot of times it's the first heat exchanger from the raw water pump that catches a bunch of crap in it.

Probably your culprit is the transmission coolers, after that check impellers, then check fuel coolers, then check heat exchangers, then risers

There are lots or reasons why a boat will run hot, anything from raw water obstructions, raw water or coolant pump, heat exchanger, coolant, over fueling, head gasket, and in a DD you could have heat transfer issues with the liners.

Also, everything in the E/R could be fine and and the boat could be overloaded with a fouled hull and running gear causing excessive drag and overfueling.

I attached a picture of a gear cooler from a few years ago.
This is a picture of the inlet side of the gear cooler from a 46 Post with TIB.
The picture is of small mussels about 1/4" long obstructing the flow.
This is what was left after most of them fell out when the hose was removed.
(btw the engine was not running hot, but I guess it was not running as cool as it could have)

The Post came from the factory with external Great South Bay type strainers.
Although I am not sure if necessary, I have added sea strainers as a back up.

Thanks for the info. It's great having a cooperative group of subject matter experts willing to share their knowledge! I hope in the future we will be able to impart some wisdom as well.

what temps were showing on the gauges?

I back up the gauges, with regular engine room checks.
I check the engines with one of those IR temp guns.
I shoot the both engines on the same spots and note any significant differences.

I also bought mechanical gauges to place in the engine room and a engine room monitor with a video screen for the bridge. I plan on focusing one camera on the engine room gauges, I just haven't gotten around to that project yet.

Sorry for the long delay in getting back on here. I am going to try the camera to look inside as soon as I get one. I think I know where I can borrow one but might as well have my own. Now I have done something else! I drained the fuel down on stbd eng. blew thru the line and now I am saying to myself "self, that was stupid, now you have to pick up fuel again!" Any suggestions on doing this? I really don't want to put my lips around the hose and pull a suction like I we used to do for gas but if I have to, then I have to.......

You might have a prime pump!

most Posts that I have seen have a OEM priming pump with a 3 way switch.
The pump I have easily fills the racors. (I added dual racors)
the mechanical lift pump on the engines will usually do the rest.

I have never had a problem with these engines bleeding air from the lines.

The priming pump also easily pushes fuel to the generator. I have never had to crack open an injector line to bleed air on the generator either.

The spin on filters I usually fill with Diesel Kleen,

Not that I have seen. Flex hose to Dahl filter, from there to fuel pump to secondary filter to the head. I have a couple theories that I will try such as use a funnel and fill the line, then fill the filters and use a neat trick the capt in the next slip showed me for filling the fuel rail.