Hello, what is the best way to test the smoke unit, should it read a certain resistance when out of the engine?
Thanks,
Frank M
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If you have it out of the engine just hook it to your transformer. It should get hot.
Jim, thank you, I will try that, how quick will it get hot, should I put some fluid in it?
Frank M
The biggest problem you will have with a pill type smoke unit is they get plugged up with the wax. The heating element is very reliable. Some of the reproduction heating units have higher resistance and do not smoke as well as the older units. Wax in the bowl is not a problem as it will just melt as the unit warms up. Where there can be a problem is if the wax gets into the air inlet passages or on to the piston. This usually can be cleaned up with a heat gun. In my experience the biggest problem with postwar smoke units is getting the piston to work reliability. It needs to have a long stroke. Later engines got a spring to push the piston all the way back down. This spring can be added to older smoke units. The piston and cylinder need to be clean and smooth so the piston can move freely. The piston drive linkage needs to allow full travel. The 773 is well known for its linkage not fitting properly resulting in shorting the stroke. I would have to check to be sure, but I think the correct resistance for a postwar smoke unit is 17 ohms, cold.
