Bringing an Old Diesel Back to Life

[jeffjd]

Originally Posted by neptunesjester

Having done this before, I would pull the injectors and fill each cylinder up with Marvel Mystery Oil and let the motor sit for a week before attempting to turn it over. Rust on the cylinder walls can do a number on the rings when everything is dry from sitting for so long. I had two motors each with a siezed piston. Marvel freed both up, honed the cylinders and been running on them since 2008.

As others have recommended, I'd pull the heads and lightly hone the cylinders as step one. While honing you'll turn the engine over by hand and it should spin easily with no sticky spots. Once done, put the head(s) back on and do a compression check. If that passes, then start refurbing the fuel and cooling system.

Also check the exhaust manifold for any signs of cracks or corrosion since a bad manifold can screw up a newly rebuilt motor - ask me how I know

Later,
NJ


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Do you actually hone the cylinder walls while the pistons are in the engine? Can you please provide a little more details how this is done?

Thx Jeff


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[neptunesjester]

Hi Jeffjd,
Yes I left the pistons in. The pistons that siezed were near the top of their throw when they seized. I just turned the motor over to drop them to the bottom once the MMO did its magic. I proceeded to lightly hone the top of the sleeve to remove rust. After reassembling all cylinders passed compression check. I have hundreds of hours on them now.

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[DennisDW]

My Perkins 4-154 sat for 13 years. I pulled the injectors and poured in Marvel mystery oil and let it sit. 'Changed the oil and pulled the starter and checked it on the bench. I used a breaker bar on the crank and couldn't budge it. I turned around to pick up a big hammer and when I turned back the crank had rotated under the weight of the bar by itself! Go figure. I put in the injectors and opened them to bleed. It started on tightening the first injector line. This was unexpected and the subsequent mess from the other 3 spraying fuel was impressive.

'Have many hours on the engine since and no problems.
Good Luck,
Dennis

[shakey doug]

This is how I would do it. Firstly ask for make and model of engine involved with this info I should be able to ascertain the following. 2 or 4 stroke, type of injection system, aspiration system, compression relief system, known engine make problem areas, motor configuration. Ask owner/agent type of exhaust system fitted, final drive type, type of cooling used ie raw water, keel , heat exch, mounting system. Hopefully armed with this info a relevant job plan can be put in place.