My Universal 25XP has been starting and running like a champ all summer and fall...until now. The temps are in the 40's and 50's and the engine in my 89 Catalina 30 will not even cough. I suspect glow plug problems but I do get a drop on my voltmeter when I turn the ignition switch to glow plug. I can hear also the electric fuel pump slow down. I installed a solenoid on the glow plug circuit this year and can hear it clicking when activated. Have also tried bypassing the solenoid without result. I usually apply the glow plugs for about 12-15 seconds before starting. When I touch the area around the glow plugs I do not feel anything on the way of heat (don't know if I should). The engine is turning smoothly. Any suggestions?