Unrestricted 12v supply to an 11v plug?

[advlars]

Hey guys. Im ditching my malfunctioning superglow system and I built a simple relay-on-a-momentary-switch manual system. I live in Southern California so I wont need this every day, but I spend enough time in the mountains that I do need reliable glowplugs.

I cant seem to find a true 12v plug that fits my 5l though. Can I run 12v to my 11v plugs? Or do I need a resistor of some kind in the system? If I do run them directly will it just shorten the life of the plug, or will they blow-up/ warp sideways?

 

[doug720]

I don't know the SuperGlow system, but I made a manual glow plug system for the Isuzu 4BD2 I swapped into my 60. It works perfectly.

You can search - Wilson Switch - for a manual system also. wilson switch glow plugs - Google Search

I used a Ford style started relay activated by a push button momentary switch on the dash. With the relay, you can run small wire to the switch, and large for the power supply and feed to the glow plugs. They are easy to set up, wire and operate.

Go for it.

 

[advlars]

Ah, yes. Wilson switch! Thats what its called.

The new wilson relay is already done and ready. Ive got a momentary toggle in my dash to a 40amp relay, and 10 guage wire to the busbar. Ive also got an led in the dash that draws off the busbar so Ill be able to see if something ever goes wrong and the switch or the relay keep feeding power.

The part im stuck on now is the plug ratings. The stock plugs from the JDM motor were 11v. I was going to use them but discovered theyre all duds! Now that I have to spend $120 on new plugs anyway, I want to confirm the 11v will work correctly before I burn them out in a week.

 

[duncanrm]

y. Ive got a momentary toggle in my dash to a 40amp relay

40A is likely to be a bit under-rated.. I'm not sure what plug you're going to end up with but common 12V glow plugs are around 10A per plug.

 

[advlars]

I had some concern about that, but I had a spare 40 sitting around. I'll be sure to check the current draw with my amp meter

 

[duncanrm]

I had some concern about that, but I had a spare 40 sitting around. I'll be sure to check the current draw with my amp meter

You have an Amp meter capable of measuring > 40A??? Or do you have a clamp style meter?

If you've got a regular run of the mill multimeter it'll likely be only good for 10A..

 

[advlars]

Good looking out duncan! But yes, I have a nice clamp style setup. I think it reads 100 amps?

 

[KiwiDan80]

An 11v plug is designed to have 12v applied to it. The lower rated voltage is so that the plug heats quickly, the rule of thumb we use at work is an 11v plug at 12v will take 11 seconds to heat or a 6.5v ceramic plug will take 6.5 seconds. You will only burn them out if you keep power applied for a long time.

Some Toyota systems use 2 glow relays, one is pre heat and the other is after glow. The after glow relay also has a resistor in the circuit which is mounted into the under side of the intake manifold. The resistor drops the voltage to around 6v at the plugs to maintain tip temperature during engine warm up, this is usually switched off at about 60 degree's Celsius coolant temp.

I would use a higher rated relay than 40 amp as the contacts may stick together and burn you plugs out. We use 100 amp continuous solenoids for glow systems

 

[advlars]

Awesome info Dan. My original system was basically what you just described: 12v preglow and 6v afterglow through a resistor. But I was never clear if the plugs in the super glow system were actually supposed to be 12v or 6 volt. Mine were 7s, but definitely not oem. Also I wasn't sure if there was something special about the internals of the superglow glow plug or if all lower rated glow plugs could take 12v to build heat faster. Guess I'll go with the 11's I found!

Sounds like everyones in agreement I need to upgrade the relay. Ill start shopping around. As I mentioned though, I wired my LED signal wire into the busbar, so I can at least be sure I see if the relay sticks and then pull the fuse or whatever. I feel like thats a good precaution regardless of relay size.

On a bit of a tangent, can anyone explain what purpose the afterglow really serves? I would think that once the engine is running the precombustion chamber stays plenty hot without it?

 

[KiwiDan80]

It is to help the engine burn cleaner until it warms up. I have seen some engines without it or with it no longer connected miss after start up and smoke if left idling on cold starts.

 

[Greg_B]

Awesome info Dan. My original system was basically what you just described: 12v preglow and 6v afterglow through a resistor. But I was never clear if the plugs in the super glow system were actually supposed to be 12v or 6 volt. Mine were 7s, but definitely not oem. Also I wasn't sure if there was something special about the internals of the superglow glow plug or if all lower rated glow plugs could take 12v to build heat faster. Guess I'll go with the 11's I found!

Sounds like everyones in agreement I need to upgrade the relay. Ill start shopping around. As I mentioned though, I wired my LED signal wire into the busbar, so I can at least be sure I see if the relay sticks and then pull the fuse or whatever. I feel like thats a good precaution regardless of relay size.

On a bit of a tangent, can anyone explain what purpose the afterglow really serves? I would think that once the engine is running the precombustion chamber stays plenty hot without it?

Good replies above that explain the glow systema and afterglow. An advantage of the automatic afterglow is in really cold weather you don't have to feather the glow button to keep the tips warm, if it keeps coughing shortly after starting. If you look at the manual versus superglow voltage numbers The Diesel Part number thread. NO CHIT CHAT or PARTS # REQUESTS! in the link you'll see you are okay.

For my Wilson Switch I used a Cole Hersee 24213 200A continuous duty solenoid in my 1HD-T conversion. Overkill, but know I will be okay. Folks have also used Ford starter relays: wilson switch conversion

hth's
gb

 

[hj 60]

Afterglow (I hope to keep it working forever) is more measured in seconds than in minutes, even at -18 celcius the afterglow is half of start glow voltage and after a few seconds it stops (in my HJ) When warm it does not/barely afterglow, when operating temp it does not afterglow.

When the glow tips are a bit worn the cold diesel cools it all and makes starting difficult, mine are now almost 100k kilometers old and with cold starts it seems that one is not really helping like it was when new, now finding the that one is not easy (to me)
So I wait a bit and replace them all with new, dont know if others manage to get a good (in engine) test to find (a bit worn/broken) glowplugs.
So how do you measure the difference between a new and old glowplug is my question, I think

 

[asutherland]

This is a good thread, lots of good info here.

With my new LX450 I'm moving to a slightly different and more configurable/manual setup than stock superglow system. With the old 1HD-T system, I would often experience very harsh cold starts in temps below -15C. During the winter my 1HD-T sees temps Avg ~-5C to -15C, and sometimes (for a couple weeks a year) into the mid -20C's and even -30Cs.

I've replaced all 6 plugs with HKT PT152's, which is an oem replacement 11/12V plug. I've maintained the main pre-glow (full power) large Toyota relay in the engine bay to supply the power from battery to glow plug bus bar. To trigger that, rather than use a "wilson switch", I'm going to use one of these adjustable pre/post glow systems from Australia: Bogaard DGT-2 Glow Plug Timers :: Features and Installation - Bogaard Distributors Pty Ltd

This will provide an adjustable pre-glow full voltage glow, and an after-glow to minimize rough idling/smoking when very cold.

I can turn up the pre-timer in the winter season, and in the summer I can simply turn the key to start (without waiting, which according to Bogaard will cancel the pre-glow as well as the after-glow.) If I want I could even hook a toggle switch to the Bogaard system to disable glow completely in the warm summers.

@KiwiDan80 , thanks for the info. What's a "long time" to damage the plug? If it's in the winter and I have pre-glow set to a full 30 seconds, is that too long? I've read elsewhere afterglow on these systems can be either half-voltage or a "pulsed" full voltage (on for 2 secs, off for 2 secs, repeat) which is the difference between the two Bogaard models. 60 degrees C for coolant temp probably takes a good few minutes in sub-zero temperatures I would think. Recalling how my truck would rough start/idle in cold, I believe it straightened itself out after approx 2-3 mins, of course depending on the ambient temps.

 

[asutherland]

Another question... out of the two glow relays,

28610-17020
28610-17060

Which is the #1 Glow Relay in the schmatic and which is #2 Glow Relay? I BELIEVE ..20 is the MAIN GLOW Relay #1 (full 12V to plugs).

Dropbox - Glow Plug Schematic 2.jpg