CHT not working

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STEEL
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CHT not working

Postby STEEL » Mon Mar 18, 2013 10:01 am

Since trailering my trike to its new home, I have noticed that my trikes CHT guage is not working.
I am not sure if the vibration on the road did something or how well it even worked before I bought the trike.
I have opened the pod to see if any loose wires, but all looks in good order.
I am not sure if the problem lies on the sensor (motor) side. (ROTAX 503 DCDI).
Anyone have some advice on what to look for, or had similar experience and if the sensor's have a "lifespan" or what else it could be.
Thank you.
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V
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Re: CHT not working

Postby V » Mon Mar 18, 2013 1:26 pm

Hi Steel, I had many problems with the CHT sensor breaking at the engine side on my 503 DCDI. I used the type that's a ring (like a washer) and goes under the spark plug. Very easy to damage the wire when changing the plugs. Moved both sensors under a head bolts, out of harms way. This way they register a slightly lower temperature, but at least they don't break anymore.

So check for wires (usually yellow and thin) other than the ignition lead (usually black or blue and thick) going to you spark plugs and tug on them, see whether they've broken off the rings.

Another possibility is that the CHT sensor leads were not long enough and had to be joined/extended to reach to the pod. This join/connector can be a source of your problems. Trace the leads from the engine all the way to the pod. On a Windlass trike the connector might be in the battery box.

Cheers,

V.
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Re: CHT not working

Postby STEEL » Mon Mar 18, 2013 3:41 pm

V,
Thanks for the advice,
will have a look and probably move them like you suggested.
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Re: CHT not working

Postby V » Tue Mar 19, 2013 1:15 pm

Hi Steel, my pleasure. When moving the CHT probe to the head bolt, make sure to tighten with the correct torque.

Cheers,

V.
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Re: CHT not working

Postby nickjaxe » Fri Mar 22, 2013 9:16 pm

Are the wires still on the back of the gauge...you can check the gauge with a multi tester set in the ohms range for needle deflection.

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STEEL
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Re: CHT not working

Postby STEEL » Mon Oct 21, 2013 10:57 am

Hi,
The CHT sensor is the washer type and is fixed under one of the "head" bolts already, but seemed in tact (the washer that is)
There is a joint and "joiners" are proper electrical ones along the cable. Should this be a continous cable with no joints.
The cables are still in the back of the meter, but did not check if the meter is faulty/ still working (using a voltmeter set on ohms).
Should I just replace the entire sensor and cable?
Any suggestions were I could get one of these?
Thanks in advance.
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Re: CHT not working

Postby nickjaxe » Mon Oct 21, 2013 6:43 pm

Before you bin the sender...check all connections in the line...the current from the sender is tiny...a tiny bit of resistance and it wont work...you could further test the sender without running the motor by heating the sender with a small blow torch..not much heat req on the CHT sender...not like the EGT,

If your multi tester can read in low Mv you could disconcert the wire from the back of the meter and see if your getting a reading...if connected back to front it just will not work.
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Re: CHT not working

Postby Morph » Tue Oct 22, 2013 1:00 pm

Check the earth lead to the guage
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Re: CHT not working

Postby nickjaxe » Tue Oct 22, 2013 4:53 pm

Do they have one????
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Re: CHT not working

Postby Duck Rogers » Wed Oct 23, 2013 10:15 am

nickjaxe wrote:Do they have one????
Nope...they don't
Airspeed, altitude, or brains....you always need at least two
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Re: CHT not working

Postby nicow » Wed Oct 23, 2013 11:50 am

Duck Rogers wrote:
nickjaxe wrote:Do they have one????
Nope...they don't
(^^)
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