Short Circuited

[Gary L.]

I'm at wits end. Last weekend, I was able to fire up the diesel, my Universal 18, go down river and sail; and even though I had blown another fuse restarting the engine, it fired back up and returned us back to our dock. Now it just keeps blowing fuses. What happens is that whenever, I push in the glow plug switch, I blow a fuse. I checked the switch for a short, figuring that moisture may have gotten inside like before, and this is the replacement. I checked the amp gauge and replaced it. There is no moisture on the connections, no frayed or exposed wires, and I have checked and rechecked the wiring diagrams to insure that everything is hoocked up correctly. It just seems that when I push the switch it draws either too much or shorts out the circuit. Has anybody experienced this before?

Thanks beforehand.

Gary Lapine
Red Witch III
CD30C, #339
Somerset, MA



dory26@attbi.com

[Jeff Funston]

Is it the correct fuse for your glow plugs? You can check the resistance of the circuit with an ohm meter, disconnect the battery first, maybe some with a U18 can verify what the resistance is supposed to be cold.....



jefffNospam@pinn.net

[Ken Coit]

Gary,


If this is a new phenomenon after it had worked just fine for quite awhile, then I might suspect either a short in the wiring between the switch and the glow plugs or a bad (shorted) glow plug. On the other hand, if the boat is new to you, maybe the wrong fuse is being used. After a bit of research, I am guessing that the current to each glow plug might be 5 to 12 amps for a total of 15 to 36 Amps for the three cylinder engine. Thus, resistance of each plug would be as low as 1 or 2 ohms; if they measure a dead short or more resistance, then they are probably bad. Unfortunately, if they are bad and measure high resistance, that won't solve your original problem.


I would also think that this time of year you shouldn't really need the glow plugs at all, but maybe the engine is worn and needs all the help it can get to reach combustion pressure; maybe it was designed that way. Our Perkins 4-108 starts in a very few seconds with no glow plugs.


Good luck,


Ken

I'm at wits end. Last weekend, I was able to fire up the diesel, my Universal 18, go down river and sail; and even though I had blown another fuse restarting the engine, it fired back up and returned us back to our dock. Now it just keeps blowing fuses. What happens is that whenever, I push in the glow plug switch, I blow a fuse. I checked the switch for a short, figuring that moisture may have gotten inside like before, and this is the replacement. I checked the amp gauge and replaced it. There is no moisture on the connections, no frayed or exposed wires, and I have checked and rechecked the wiring diagrams to insure that everything is hoocked up correctly. It just seems that when I push the switch it draws either too much or shorts out the circuit. Has anybody experienced this before?

Thanks beforehand.

Gary Lapine
Red Witch III
CD30C, #339
Somerset, MA

parfaitNOSPAM@nc.rr.com

[Tom]

You might try disconnecting the wired from the glow plugs and then pressing the button. If the fuse still blows that will tell you it's in the wiring not in the glowplugs. If the fuse doesn't blow when the glowplugs aren't attached one or more of your glowplugs is probably bad. Unscrew them and inspect them. When a glow plug goes bad it usually burns a hole in the side of the pin that goes in the engine or the tip explodes. You may be able to see which one(s) is bad. If they look OK you can put 12 volts across them by putting the positive lead to the center post and the negative lead to the body. Within 10 or 15 seconds the tip of the plug should glow red hot. You obviously don't touch it when it's hot. You can also check continuity through the plug with the positive lead from your meter to the center post and the negative lead to the body with the dial set on ohms. Or take them to you local glow plug shop and ask them to test them for you. New ones cost about $60 each so they are happy to do this for you. While the glowplugs are out put the meter (set on DC volts scale) between the wires (one at a time) and the engine block and see if you read 12 to 14 volts when you press the glowplug button. Chances are you've got a short circuit either inside one of the glowplugs or in your wiring. You can disconnect the wire from the dowhill side of the glowplug button and see if it still blows a fuse when you press it. The idea is that you can figure out where the short is by isolating sections of the circuit one at a time.

I'm at wits end. Last weekend, I was able to fire up the diesel, my Universal 18, go down river and sail; and even though I had blown another fuse restarting the engine, it fired back up and returned us back to our dock. Now it just keeps blowing fuses. What happens is that whenever, I push in the glow plug switch, I blow a fuse. I checked the switch for a short, figuring that moisture may have gotten inside like before, and this is the replacement. I checked the amp gauge and replaced it. There is no moisture on the connections, no frayed or exposed wires, and I have checked and rechecked the wiring diagrams to insure that everything is hoocked up correctly. It just seems that when I push the switch it draws either too much or shorts out the circuit. Has anybody experienced this before?

Thanks beforehand.

Gary Lapine
Red Witch III
CD30C, #339
Somerset, MA

TomCambria@mindsprng.com

[D. Stump, Hanalei]

Captain Lapine,

Sorry, couldn't resist.........The recommendations you have already gotten are exactly what I would expect... I would also expect a grounded glow plug, sorry, that is expensive!

D. Stump
s/v Hanalei, CD-30C
with Universal 18.

[Gary L.]

I just want to thank everyone, including Captain Stump, for their fine advise. The Red Witch is now safely esconced on her mooring, and as soon as I can get back down there ( I had to defend this country, this past weekend) I will work through each of your suggestions, I do believe that the late Captain Moore left some glow plugs on board.

This board is so great, that I have recommended it to any boater I meet. I commend the page developer for their hard work in both the development and maintenence of this site, as well as all of you who contribute, there simply is no better data base anywhere.

Gary Lapine
Red Witch III
CD30C, #339
Somerset, MA

dory26@attbi.com

[Chris Scheck]

I must second Gary's comments about this board ... it has increased my enjoyment of my boat, and sailing in general, tremendously ... especially in the off-season.

The advice I have gotten about all kinds of repairs -- mechanical, glass and brightwork -- is much appreciated. More detailed and real-world than I have seen in any book. And written with such wit and erudition ... more proof that CD owners are smarter than owners of other brands!

Chris Scheck
RAGTIME CD33 #117
Newport RI



cscheck@aol.com