Temperature and detectors - Marine engines

[Guest]

So here I am with a Perkins 4107 fitted to my priude and joy. No rev counter, no oil pressure gauge, no temperature gauge etc.
As a quick and temporary answer - I wish to bind a digital thermometer to the exhaust pipe and also one to engine casing. Giving a dual indication of temperatures.

Question - what would be acceptable location to fix the probe to on the engine and what temperature range would be expected for a raw-water cooled engine ... ? Also the exhaust pipe - I assume that probe is best UNDER the pipe to detect cooling water flow as well as pipe temperature ... how close to engine and what would again would be expected temperature range ?

/forums/images/graemlins/confused.gif

 

[iangrant]

Nigel
As a thought - why not take a wander into the scrapyard next door to your marina. I reckon they must have a shelf full of instruments that you could plug onto the old donk. Certainly your alternator must have a takeoff for a rev counter, andI'm sure there are senders on your engine for temp. An oil guage can be connected (non electrical) by a pipe into the pressure switch hole.

Good luck - just an idea or there is always good old Ebay - I just bought an ameter for 9 quid!

Ian

 

[Guest]

Thought about it ...

The breakers yard next to yard hasn't been too successful with me ... have got stuff there twice and both were duff !!

I was thinking to just tack a probe along the exhaust pipe as basic indicator that cooling was working ... and then thought for another tenner - stick one on the engine.
As to gauges .... I had a load of gauges ready to fit - then when boat flooded - they all got full of sea-water and had to be dumped.

Its actually interesting to know what temps you would expect an engine to run at ....

But I'll have a word with nthem when I get back ....

Cheers

 

[JAYEL]

Nigel. Found something at www.manddsmallengine.com/tiny/tach/ that might suit you Sir! UK contact, itco@btopenworld.com, Richard Dunn. I have just ordered one for my YSE8.

 

[Guest]

tiny/tach ....

link doesn't work for me ....

 

[bob_tyler]

Re: tiny/tach ....

Nigel,

Delete all after .com and you get on the home page of the site. Work it out from there.

Bob

 

[pete]

Hi Nigel
I fitted an exhaust alarm from here http://www.borelmfg.com/products_v6andv8engines_alarm.htm they were very helpfull and I was impressed with the price and the product even though they had to send it from USA . They recomend fitting the sensor on top of the exhaust hose and about 1/4 in behind the hose clips on the exhaust manifold (I suppose it is the rubber you are trying to protect ) It alarms at 170degrees f.
I also fitted a water flow switch from farnell.com (around £13 00 +p&p ) to the water inlet below the raw water pump and linked this into the exhaust alarm panel
Belt and braces.
Pete

 

[BobOwen]

There is another way.

There is a type of cable known as thermocouple (tc) cable. This is two core small diameter stuff. You run that to any point, strip and twist the ends together and bolt it to any item. This forms a tc junction. Then you need a thermocouple reading device which reads temperature direct fom this cable.

Such devices can even be a cheap multimeter though there are dedictated devices available. Check RS and / or Google for thermocouple devices and temperature indicators.

With one indicator, you could wire as many points as you want to a selector switch, then wire that to the reader. You could then monitor as many points as you want. But only one at a time.

I have a few new digital temperature reading controllers from Eurotherm (I mis ordered these for a recent overseas job and would love to get rid of them). (They have tiny 2" x 1/2" displays, with bright temperature display).

They do need a mains supply (via tiny inverter - almost negligible load) and some familiarity with programming controllers if its of any interest to you. If you need any more info or help regarding these let me know.

 

[steve28]

Nigel,

the only downside to an external temp sensors would be the lower reading it would give, on my fresh water cooled yanmar, the temp cycled between 75 and 80 degrees. This kit i purchased from lsuk i think it was 21 ish pounds, they also do a gauge and sensor to suit a raw water cooled system.
I assume they also do an oil pressure type as well.


I fitted a durite tacho with hour meter from lsuk as well come to think about it, this involved opening the alternator and solering a wire on the stator.

hope this may help

steve

 

[Breoch]

Re: Thought about it ...

Hi Nigel

A Thornycroft/BMC 1500 ran at 84 degrees C, give or take a couple depending upon load and time at full throttle.

 

[steve6367]

Do you have a link to flow meter on Farnell? I would be interested, but cant seem to find it.........

 

[Colvic Watson]

On their UK site put 730889 in the search box and it comes up with the part. Spoke to Farnell's and it is a simple flow operated contact switch which is then connected to say a bulb to show the water is either flowing or not. Brilliant low-tech solution. Available in 22mm or 15mm. Just bought one.

 

[andy_wilson]

Raw water engines run cool, 50 to 60 deg to reduce corrosion. Anywhere around the thermostat housing would be sensible.

On the exhaust, depends on the temp. the pipe is rated at. Nearer the elbow the better.

Best to fit and monitor when you know all is running well, then you will know what represents a problem like damaged impellor or blocked intake.

 

[Guest]

I would love to ...

Have all the correct gauges and probes / detectors fitted etc.... but alas I am a skin-flint and cannot broing myself to spend such money .... so a couple of thermo probes in strategic places will do for now ....

Cheers all ...