How long should I heat up my glo plugs on my universal M3-20 (18 hp) ? I usually let them heat for about 30 secs before cranking the engine. Can any damage be done by overheating them ? Thanks !
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Glow Plugs
Yep, overdoing it can burn out the glow plugs. Pre-heat only as long as required to effect a start - experiment & experience will determine durations at different temperatures. 30 Seconds should not present any great danger. Regards, Gord
Yep, overdoing it can burn out the glow plugs. Pre-heat only as long as required to effect a start - experiment & experience will determine durations at different temperatures. 30 Seconds should not present any great danger. Regards, Gord
to glow or not to glow
I usually hold the toggle for the glow plug about 25 seconds, and then start the engine. I had a situation last week where i ran the engine for about 15 minutes and then we sailed for about 2 hours, my son forgot the toggle and just turned the key to start and the engine started right up. I've done this several time since then and it starts everytime. is there a chance i could damage the engine by doing this? If anyone has any thoughts on it please get back to me. Thanks
I usually hold the toggle for the glow plug about 25 seconds, and then start the engine. I had a situation last week where i ran the engine for about 15 minutes and then we sailed for about 2 hours, my son forgot the toggle and just turned the key to start and the engine started right up. I've done this several time since then and it starts everytime. is there a chance i could damage the engine by doing this? If anyone has any thoughts on it please get back to me. Thanks
Glow Plugs
The glow plugs are only there to get a cold engine to start firing. If the engine is still warm, it could be started without the use of the glow plugs without harm. You can reduce the amount of time you need to hold the glow plug button down by installing a solenoid. This reduces the length of wire that the current has to run through. Instead of going from the battery to the key or pushbutton in the cockpit, and then back to the engine, it just goes through the solenoid from the batteries directly to the glow plugs. The link is to a refence source from the C34 website.
The glow plugs are only there to get a cold engine to start firing. If the engine is still warm, it could be started without the use of the glow plugs without harm. You can reduce the amount of time you need to hold the glow plug button down by installing a solenoid. This reduces the length of wire that the current has to run through. Instead of going from the battery to the key or pushbutton in the cockpit, and then back to the engine, it just goes through the solenoid from the batteries directly to the glow plugs. The link is to a refence source from the C34 website.
My experience
I have the same engine and have 5 years practice. I have found that 15 seconds works every time regardless of outside temperature. I sail all year but of course we do not have severe winters in th Pacific Northwest. I can normally start the enjine without the glow plugs for 2 to 3 hour after.it has been running. Hope this helps. David Four Feathers
I have the same engine and have 5 years practice. I have found that 15 seconds works every time regardless of outside temperature. I sail all year but of course we do not have severe winters in th Pacific Northwest. I can normally start the enjine without the glow plugs for 2 to 3 hour after.it has been running. Hope this helps. David Four Feathers
glow plugs
30 seconds does it for my Universal. A word of caution...I have owned a few diesel cars...do not try to start it while having the glowplugs engaged. It will burn them out. Griffin
30 seconds does it for my Universal. A word of caution...I have owned a few diesel cars...do not try to start it while having the glowplugs engaged. It will burn them out. Griffin
Glow & Start Separately
Griffin's right. Hold the glow plug button on, then release it. Then hit the starter. I'm not sure it would burn them out, but sometimes your starting battery will not be able to handle the combined electrical load of BOTH the starter motor and the glow plugs, both of which draw short time but large amounts of current. There is no reason to have them both on at the same time. Stu
Griffin's right. Hold the glow plug button on, then release it. Then hit the starter. I'm not sure it would burn them out, but sometimes your starting battery will not be able to handle the combined electrical load of BOTH the starter motor and the glow plugs, both of which draw short time but large amounts of current. There is no reason to have them both on at the same time. Stu
Wait, dont hold both at same time ?
First of all, thanks for all your input about glow plug heat up time. I've been starting my engine for 2.5 years by turning the key, holding it (for the glow plugs), and then hitting the engine start button while still holding the key. When the engine starts I immediately release both. Is this wrong ?
First of all, thanks for all your input about glow plug heat up time. I've been starting my engine for 2.5 years by turning the key, holding it (for the glow plugs), and then hitting the engine start button while still holding the key. When the engine starts I immediately release both. Is this wrong ?
Not wrong, just not necessary
Michael Think about how it works. The glow plugs heat up the chamber for when the pistons first start going up and down from the starter, they have a HOT chamber that helps the fuel to ignite. Remember that there are no spark plugs in diesels. You don't need to keep the glow plugs hot at the same time you hit the starter. The few seconds between stopping the glow and hitting the starter will not affect the purpose of the glow plugs. That's why, for instance, hot engines will start without the glow plugs. The 12-15 seconds (with solenoids) or 30 seconds, without solenoids, will be enough to heat the chambers for ignition. No need to keep them both going at any time. You might even find that your engine turns over more quickly if you release the glow plug button before you hit the starter. Stu
Michael Think about how it works. The glow plugs heat up the chamber for when the pistons first start going up and down from the starter, they have a HOT chamber that helps the fuel to ignite. Remember that there are no spark plugs in diesels. You don't need to keep the glow plugs hot at the same time you hit the starter. The few seconds between stopping the glow and hitting the starter will not affect the purpose of the glow plugs. That's why, for instance, hot engines will start without the glow plugs. The 12-15 seconds (with solenoids) or 30 seconds, without solenoids, will be enough to heat the chambers for ignition. No need to keep them both going at any time. You might even find that your engine turns over more quickly if you release the glow plug button before you hit the starter. Stu
glow plugs and starter
On my O'Day 31 the starter button will not work unless the glow plug button is held down at the same time. I always thought that was wierd, using all that juice at the same time, but that's just the way it is wired. Should I try to re-wire the switches?
On my O'Day 31 the starter button will not work unless the glow plug button is held down at the same time. I always thought that was wierd, using all that juice at the same time, but that's just the way it is wired. Should I try to re-wire the switches?
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