Both rebuilds of Renko's Detroit Diesel 4-71, from taking it out of the boat to the first sea trial, in the order the videos were made. Most of the work was done with Adrian, a Detroit Diesel mechanic.

The first rebuild

Renko's Detroit Diesel had seized, so in 2019 it came out of the boat to be rebuilt. The video above is taking it out.

Teardown

I start taking the engine apart so it can be rebuilt: removing the head, the heat exchanger, the gearbox and one of the pistons.

Removing the blower

Taking the blower off the engine (after moving the boat stands for more painting).

The gearbox and heat exchangers

Taking the gearbox and heat exchangers apart ready for servicing, along with servicing the seacock gate valves and fitting a battery shelf.

Advice from the Bus Grease Monkey

Scott from the Bus Grease Monkey YouTube channel gives me some great advice on starting the 4-71 for the first time.

The engine returns

Picking up the rebuilt engine from CDA and getting it back to the workshop to put back together.

Heat exchanger cores

Cleaning and installing the cores in the three heat exchangers: the main raw water heat exchanger and the coolers for the engine and gearbox.

Putting it back together

Fitting the flywheel, damper plate, gearbox and starter motor, and starting to plumb in the cooling and oil hoses.

Cooling system and blower trouble

Making a new coolant pipe, then Adrian checks the engine before its first start and finds a few things that need fixing.

Blower, governor and fuel pump

Adrian rebuilds the blower, governor and fuel pump.

First start

Adrian and I finish the engine and fire it up for the first time since the rebuild.

Preparing the engine bay

Getting the engine bay ready for the engine to go back in.

Craning it into the boat

Towing Renko back to the mainland to crane the engine back in.

Coarse alignment

Adding jacking screws to the engine mount shims and roughly aligning the engine with the propeller shaft.

First start in the boat

Bolting up the propeller shaft flange, connecting the controls and starting the engine in the boat for the first time.

Spinning the prop

Finishing the raw water plumbing, then putting the engine in gear to spin the propeller.

First sea trial

A finer alignment and a short sea trial.

The second rebuild

At the end of 2020 the engine came out again so Adrian and I could fix an oil leak and make some improvements.

Removing the engine again

Taking the engine out and up to Adrian's.

Diagnosing the oil leak

Tearing the engine down to find the oil leak, which turns out to be the wrist pin seals, and adding an air compressor while it's out.

Injectors, cam rollers and oil pressure

Adjusting the cam rollers, replacing the oil pump regulator springs to bring the oil pressure back up, and how the injectors work.

Assembling the engine

Reinstalling and shimming the oil pump, and a new oil pickup for the deep sump.

First start of the 4-71

Final assembly, then Adrian sets the injector heights and valve lash and we fire it up.

Finishing touches

Finishing the engine and painting it ready to go back in the boat.

Back into Renko

The engine goes back into Renko, then a new exhaust, alignment and starting it up.