My Engine

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XUD Marine
Posts: 40
Joined: 30 Jun 2019, 10:14
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Re: My Engine

Unread post by XUD Marine »

It's been a while since I gave an update, but things have slowed down a bit, so not much to report.
I got the new thermistor, but it turned out on testing that did not match the gauge, so ended up getting another sensor/gauge pair. At least they were not expensive.
Anyway the progress this weekend, the engine beds are nearly ready, a job I had been putting off.
IMG_20191222_162827_BURST1577032107712.jpg
IMG_20191222_162855_BURST1577032135771.jpg
I ended up using some 4x4 fence posts. They may not look like much, but they took some fitting. The space for the original engine was off-set form the centre, so the bilge floor there is asymetrical, the angle of slope inward varies along the length, the starboard side the bearer is sat on ribs, but the port is not. But I needed to get the main bearers level and even, so that involved a lot of measuring, marking, sawing and chiseling until they were level at even heights.
The engine footprint is only 2 foot long, but I made the bearers 5 foot to spread the weight on the hull. They are stuck down now with just expanding foam, which holds them in place and fills any discrepancies in my fitting.
The wedges, which are 3 foot long, are not yet fastened, though the two parts are glued together. My idea is to leave them loose, then try sitting the engine on them, then I can move them back or forward, and the engine up and down them to find the right height level to bring the gearbox flange in-line with the prop shaft flange (seen at the back) with the angle remaining a constant.
I can fine tune the angle and height with the nuts on the rubberised mounting feet, but want it somewhere close to begin with.
feet01.jpg
Once I know were the wedges will sit, where the feet sit on the wedges and where the front of the engine will be, I will move the engine off out the way, then trim off the front of the wedges, fasten the wedges to the bearers, fit a bulkhead in front of the engine (I may leave a removable, but watertight service hatch in that) and fibre-glass over the lot to seal and fasten it to the hull. After a lick of paint, it will be ready to sit the engine on and fasten down the feet.
I may put a mini bulkhead of a couple of inches between the bearers at the back, just to comply with the "Boat Safety Scheme" which says you should have a tray or separate bilge compartment under the whole engine and gearbox, to contain any oil leakage, separate from the general bilge water which is pumped overboard.

I managed to get hold of a Morse controler at a good price, so that's another component found. It's a single lever for gear shift and throttle. These oftern come with a Neutral Safety Switch which prevents starting when in gear. The manual said it was an optional extra, and opening it up, mine didn't include one. Looking them up on-line, chandlers are asking about £45 for these. It's just a micro switch that sits under a cam on the gear shift mechanism that your starter circuit goes through.
Looking on Ebay, I found waterproof micro switches for £4.50. So it's official, you label something "marine" and can add an extra zero to the price tag. I don't need a high amp rating, becuase I will be firing the starer solonoid through a relay.
Off on that tangent, while I've not been doing that much hands on lately, I have been planning the electrical sysem further and have some questions about current draw for various things, for choosing suitable cables to the engine.
Where I can I would like to keep things tidy and minimal, using multi-core signal wires where I can. But I don't want to skimp on cable weight where it matters. Obviously, starter circuts, glow plugs, etc, heavy duty stuff, I know. But what about the stop solonoid, how much current does that draw, would I get away with a tiny signal wire, or does it need something more?
I think things like oil/temp warnings will be OK on signals, that's just a little light (maybe LED) and switch. What about gauges to sensors? I wouldn't think they would need much cable weight, or will volt drop over distance affect resistance and give false readings? The gauge/sensor that is different is the alt W to tacho, as it's not simply a resisitor in the circuit, but outputting a signal, I can't imagine the tacho draws much, but I'm cautious about alterantors, as I don't fully understand them. Is that safe on a little siganl wire?

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white exec
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Re: My Engine

Unread post by white exec »

XUD Marine wrote:
22 Dec 2019, 21:46
Off on that tangent, while I've not been doing that much hands on lately, I have been planning the electrical sysem further and have some questions about current draw for various things, for choosing suitable cables to the engine.
Where I can I would like to keep things tidy and minimal, using multi-core signal wires where I can. But I don't want to skimp on cable weight where it matters. Obviously, starter circuts, glow plugs, etc, heavy duty stuff, I know. But what about the stop solonoid, how much current does that draw, would I get away with a tiny signal wire, or does it need something more?
I think things like oil/temp warnings will be OK on signals, that's just a little light (maybe LED) and switch. What about gauges to sensors? I wouldn't think they would need much cable weight, or will volt drop over distance affect resistance and give false readings? The gauge/sensor that is different is the alt W to tacho, as it's not simply a resisitor in the circuit, but outputting a signal, I can't imagine the tacho draws much, but I'm cautious about alterantors, as I don't fully understand them. Is that safe on a little siganl wire?
Just been wondering how our Blue Smurf power unit was doing. One of the more interesting posts here!!

Re: cabling...

Starter solenoid itself can mop up as much as 25A, so you are right to use a relay to operate it.
25A - use 2.5mm² stranded cable.

Glow plugs (while on the subject of high current) - use 6mm² cable to and from the GP relay, and solder the eye connectors, not just crimp.

Instruments, sensors, gauges - 0.5 or 1mm² quite adequate.

Alternator - main output cable, 25mm² (70-90A capable), 16mm² (54-72A) if quite short.
Other connections to alternator (perm +12v, IGN sw +12v, warning light) - 1 or 1.5mm².
W to tacho - You could use a screened cable for this, Gnd'ing the screen. Tiny current.

Hope helpful.

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Pug_XUD_KeenAmateur
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Joined: 22 Apr 2013, 17:24
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Re: My Engine

Unread post by Pug_XUD_KeenAmateur »

Sounds sensible, lets hope my probably inadequate Solenoid and GP cables hold for the purposes of engine testing, when I eventually get around to it

GoceKU
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Joined: 06 May 2020, 13:47
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Re: My Engine

Unread post by GoceKU »

I think i have the same engine, but a bit older, come out of a 1983 peugeot 305 and the title says it's a 1905cc 47 kw unit, what did happen did the owner get this one running ?
DSC_0002JPG.jpg.0d67ce22e1c35bb480125a54cb4245f9.jpg

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white exec
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Re: My Engine

Unread post by white exec »

It all went quiet on the smurf-blue engine story. Wonder what happened?

That's an interesting cast lump on the top of the rocker cover in your photo.
The normal breather is on the oil-filler cap, so interesting to know what the other hose (and lump) is...