Mechanical starters: Anyone used them?

[a64pilot]

The APU on the helicopter I flew was hydraulically started, if it failed the first attempt, it took I think 2000 pumps on an about three ft tube to pump it back to 3000 PSI for another attempt. Thankfully it was at about a perfect height and you stood up straight to do it.
It usually wore out both crew members.

[ColinIOM]

Hi, the hydraulic system is not the way to go, the accumulators are big and very heavy and as stated already, are very hard work to pump up. The spring starter is good but also quite difficult to wind up, and you need to ensure there is good clearance around the starter for winding. Again as discussed already, they only provide a very short duration start so the engine needs to be in good condition IE good compression, and fuel at the injectors. I have used them lots of times on lifeboats as secondary starters and they do work. Some lifeboats have them fitted along with the main electrical starters and there is the possibility that the wind up starter gear is left accidentally engaged with the starting ring and someone tries the normal electrical starter which usually ends up damaging the wind up starter.
On a yacht where you would be removing the electrical starter and fitting the wind up starter, this is not an issue.
Again, as stated, a spare small back up battery and replacement starter would be my choice, you could leave the battery tapped into your solar panel so it is always fully charged.
Have fun
All the best
Colin

[hellosailor]

Always reminds me of the original (1965) "The Flight of the Phoenix".
Electric starters have made engines of all kinds, and their owners, so much happier.

[Steve Bean]

When father was at Cornell ( Mechanical Engineering, 1931) they had a diesel engine that was started with a 10-gauge shotgun blank. A friend of mine had several aircraft inertial starters that use a hand-cranked flywheel. He had one on his 75-foot schooner and said it worked well; I don't know what the engine was. I bought one from him; if I ever install it on my boat engine (Universal 32 H.P. diesel) I'll report back here. In some old WWII movies you can see somebody run up to an airplane and crank it up. Made by Bendix. I think this is the type referred to by Chala in Post 27.

[UNCIVILIZED]

Larger marine diesels are designed to be started using compreseed air, from sheet 1 of their design. Including the primary engines onboard large Naval vessels. And you can buy, or build, systems for smaller diesels which allow you to do the same. Often via using a scuba tank as the air source. Think about it, 3,300psi in the tank, yeah, it'll probably turn over a small/mid-sized diesel. And you should get more than one try at it before having to "recharge" your starting mechanism.

One other theoretical method suggested to me was to build a system to spin the diesel up to speed using a small 2-cycle, or 4-cycle engine as it's motive force. One that you can fire up with a starter cord, like on an outboard.
You'd need a way to "clutch in" such an engine onto the diesel, & then disengage it at about the same time that the diesel fires up. But the theory seems reasonable.

Guys have also DIY'd systems to start their diesels using running rigging, or even several coffee grinder pedastals linked together. One solo sailor rigged up a line to use the force of his large mainsail gybing to get his diesel up to speed for starting. There's a video of it on youtube, as well as in another thread here on CF.

Even some substantial weights, like water jugs, hoisted up the mast have sufficient energy for the job. The catch being, what happens when it's time for the jugs to end their rapid vertical descent. So think this one through quite well prior to trying it.


Question: Anyone have thoughts on the viability of loosening the injectors on one or more cylinders in order to reduce the compression first needed to start the diesel? Yes, I know it's a bit loco. As you'd then have to tighten up the injectors on a running engine, with it trying to blow jets of flame & compressed fuel/air past your wrench while you were doing it. Given that some of the cylinders wouldn't be firing initially. But I am curious as to how one might go about it. Assuming, that is, no compression release on the engine.

Also, given a compression release, might a kick starter from an older model motorcycle be adapted? There are some awfully damn powerful bikes which get started this way. Harleys included.

[a64pilot]

Old Bulldozers and the like were started with "pony" motors.
Air starting can be direct as in pressurizing the cylinders, which is tricky requiring valving and the like, or an air motor starter.
I feel certain if I had decompression levers that my Milwaukee drill would start my Yanmar 4 JHE, but I don't have decompression levers, but for a motor that did, I think the drill would start it, driving the crankshaft directly.
I had a German Army Hatz Diesel generator, you started it with a hand crank, a lever held the exhaust valve open for three turns, by that time plan was you had enough inertia going to start the thing. Worked great until Winter in Bosnia, then they were a bear to start

Just carry a spare electric starter?

[a64pilot]

Now I think about it, the WWII German ME 262 had a two stroke motor in the nose of the jet engine, look at a picture and you can see the starting rope D ring right in the nose.
Of course this little motor turned the turbine compressor to start the thing.

[a64pilot]

Starting an old D8 Cat

https://youtu.be/drAgUv41CNI

[Diesel Bill]

I once worked on an old International Harvester 3 valve engine built in the 30's or 40's.
It was a diesel with a 3rd valve separating a separate combustion chamber above the normal chamber. The extra chamber had a spark plug and magneto ignition and an updraft carburater with a small pan to drip some gasoline in and light it on fire for cold winter starting. Sounds crazy huh? This was a 6 cylinder engine. To start it you pulled a lever on the side of the engine which opened the 3rd valve and activated the magneto drive. The engine started on gas and after a few minuets the mechanism would switch over from gas and spark ignition to turn the diesel high pres. injection pump, close the 3rd valve and fire on diesel fuel. This was a true dual fuel engine. Originally it was set up to start with a hand crank but was modified with an electric starter with a chain drive to a sprocket with an over running sprag in the hub. I can't imagine starting that chunk of iron by hand with a crank. It would take two men and a boy to turn it over.

[RaymondR]

When I decided to marinize an industrial diesel I pondered on the alternate starter and decided to carry a spare.

When the engine arrived it had the wrong bell housing so I removed and trashed it and built a new one out of alloy.

Inspiration struck and when I built the new bell housing I fitted the spare on the other side, engine now has two starters which I alternate the use of.