Hello All, I need some spoon feeding to locate the sender unit in my Beta Marine 20 model BD722 as after inserting the ignition key the the three warning lights on the control panel (ie. Battery, Oil Pressure, Temperature) would come on together with the buzzer and once the engine starts they all go off after a few seconds but today the temperature warning did not light up in the first instance and remained off! I checked the obvious ie the light bulb and the connection on the panel and they are in order. As a next step I would like to check the continuity from the sender unit but was not able to find it! I could not work backwards from the control panel either! Is the fact that it it not lighting a sign that the wire is shorting to earth? Will it help to try the positives of another warning light that is functioning? thanks, Jay
Update: Is this temp sender unit I always thought it was the oil but removing the connection did not make any difference!
-- Edited by jaybeegee on Sunday 24th of February 2013 04:39:37 AM
This actually is correct. When the ignition is switched on and the engine is not running, the temp light will be off. The others will be on. The temp light is the warning of too high an engine temp (over 205 degrees F) and will only come on when the engine has reached this high temp.
Thanks again. Much appreciate you taking the time to respond.
Are you able to point me to a link or screen shot of the temperature sender unit (only if you have something handy!) ? I can see some wiring on the manual cover (next to the heat exchanger but it is not the same model I have (BD722 of 2005/6). BR
Your photo in your first post shows the temp sender. On this model, the small terminal works the alarm. To test, simply ground the terminal to the block and the alarm should sound and the temp warning light should light up at the same time.
Sorry ... I need some more spoonfeeding! So earlier today, I connected the terminal (sender unit/engine side) to the -ve of the battery via a wire extension. I did this to bypass removing the panel and not quite sure which is the +ve and/or -ve on the light/connector end! So once I connected the wire extension from the terminal on the sending unit to the battery the temperature gauge did in fact light up as you mentioned. However the alarm did not kick in! Also this was with the ignition key turned to off! Once I inserted the ignition key and gave it half a turn to the right - the temperature gauge alarm warning switched off whilst the oil pressure + battery came on together with buzzer! Is this how it should work with the igniton?! thanks,
At this point we are assuming that all systems are installed and working properly. With all the wires connected as they should be.
With the key switch in the run position, the temp light and alarm will only come on if the engine is actually overheating. This is normal.
With the key switch in the run position, we can easily check the overheat alarm circuit by removing the spade connector from the temp sender that is shown in your photo and touching the spade connector to any bare metal on the engine.
If the overheat warning circuit is working correctly the alarm will sound and the light will come on.
If this does not occur, then there is a problem in either the wiring or the panel.
Note that this check does not test the temperature switch itself.
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Best regards,
Farron
Technical Sales and Service for Beta Marine, US Ltd. Minnesott Beach, NC PH: 252-249-2473 farron@betamarineusa.com
So in summary I have some wiring problem as with the key switch in the run position and the spade connector from the temp sender connected to a bare metal on the engine, I do not get any temp light / alarm ( ... just the oil pressure and battery warning lights + alarm)!
I only got the overheat warning light with the key in the off position and the spade connector from the temp sender connected to a bare metal on the engine! Very strange indeed. thanks again for taking the time to repond.