testing twin engines before 500 mile delivery trip.

[PCUK]

Essentially yes, but there are some long stretches with no harbours or protection.
I would do a few local runs around the area first. Down to the Mar Menor and back. Lots of harbours on that leg if something starts playing up. If everything is OK after that, the engines are basically OK. Thereafter reliability on a long run needs two things - good cooling and clean fuel.
What you need to watch out for is cooling system failure on a long run - so take spare impellers and/or belts. Some self amalgamating tape, and a selection of jubilee clips. I used to take an infra red thermometer with me and point at the engine at key points to keep an eye on things.
And fuel supply.
Does the boat have racor filters with clear bowls. After all those years there is bound to be carp/water in the tanks that will start to move around. If the boat does not have such filters I would definitely change them to Racors and take a big box of spare filters. Then practice changing them. Then you can keep an eye on things as you travel.

All good advice, adding to your list of precautions with regard to fuel, perhaps a full tank clean and fuel polish would be one of the most effective deterrents against breakdown.

 

[Bouba]

Do an inventory of every engine part that came with the boat…you may find the best diesel mechanic on the planet but spares could take a month to get

 

[rigpigpaul]

Hi All, thanks for all your advice. Going to have the fuel tanks emptied and cleaned.

 

[penfold]

Do an inventory of every engine part that came with the boat…you may find the best diesel mechanic on the planet but spares could take a month to get

Good luck finding spares at all; seawater pump will probably be Jabsco, but the exhaust manifold will be unobtainium and the rest of the engine not much better given its been out of production for 5 decades and wasn't a common engine even then. If there's a Commer lorry owners club they may have contacts for used spares, or put a small ad in Heritage Commercial or similar.

 

[PCUK]

Things like ex

Good luck finding spares at all; seawater pump will probably be Jabsco, but the exhaust manifold will be unobtainium and the rest of the engine not much better given its been out of production for 5 decades and wasn't a common engine even then. If there's a Commer lorry owners club they may have contacts for used spares, or put a small ad in Heritage Commercial or similar.

Exhaust manifolds are easy to fabricate so that is one item that doesn't need worrying about. If the engines start easily and run well I can't see any reason why they would have problems.

 

[Bandit]

What is the history of the boat and servicing ??

Has the boat been regularly used for many passages of 2 hours or more or tied up and abandoned.

Engines as old as the hills, little chance of finding spares on the way.

Give a full sea trial and service.

Normal problems are coolers, overheating, dirty fuel, corrosion eg injection bends and exhaust failure, batteries etc.

 

[Seastoke]

Lorry