glow plug help on 2l 2 engine in a 86 LJ 70

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Jan 2, 2009
fort mill sc
Long story and i cant get my glow plugs to stay on long enough.

1) replaced a blown 2l engine with a 97 2l two engine.
2) the old glow plugs from the 1986 LJ are in the 97 engine as they were working better with my old wiring.
3) It seems the are engaging but not for long enough.

I am not sure if the old ones in the 97 engine were 12 volt, 24 volt, or what ever they come in for volts?

Anyway I would love some ideas. I think maybe 12 volt plugs for a 97 2l 2 engine might help, but I do not have the ECU with the same type of timer system in the 1986 LJ verus a 1997 2l 2 engine i have now.


Earlier glow plugs will most likely be 24v depending on market.

Almost all glow plugs at Toyota go to 12V in 1990.

If you are using the later harness with earlier 24v plugs, you might have an issue there and need later plugs.

That said you could have myriad issues.

Do you know exactly what model your engine came out of? And what model/year is your vehicle? If you know this information, you can just look up the glow plug part numbers and that will tell you the voltages. You can also get the manuals for both engines to learn about the glow systems.

I doubt any of the glow plugs are 24V. The later ones are most likely 11V.

If you're uncertain about things, I'd recommend bypassing the old and new timer system, and run 11V glow plugs with a relay and wilson switch setup (Control the relay with a momentary switch. Press the button for 2-10seconds depending on temperature.). You might be able to use the factory relay, or you could buy an off the shelf automotive relay rated for 100A or more.
thanks for the suggestions. the engine is from a 97 surf rider so I was told. I think I will first try to purchase 11 v plugs and see if that helps. Then go for the bypass suggested. I do not have a manual for the engine.
Hi, if you take a look at the superglowsystems wiring diagram you will see that it wont function with 11V plugs so you have to modify/by-pass it.

Working correct the superglow system on a 2l gives 12V for a few of seconds based on enginewater temp (relay 1) and then goes down to appr. 7V (relay 2) and this helps getting the glowplugs hot very fast, hi-tech back in the 80`s!

great info. I would love some detail instructions on how to by pass and what replacement plugs I should by. thanks.

rich, he mentioned super glow system.
thats likely the one for the old engine. u need to clarify which system you have on the new engine, the 97 one.

might not be a super glow anymore.
Hi Rich, like ALEXY says I mentioned the superglow system which the 2l engine is using. The 2l 2 engine uses another system with higher voltage glow plugs. In my last post I was trying to show that you cant combine the superglow system with a 2l 2 engine and 11V glowplugs without modifications.

Here in Norway its pretty common to swap from a 2l to the newer 2l 2, use 11V glowplugs and wire a wilson switch setup. I think thats the easiest way to make it function.
Just for reference. The glow plug part number for a 1986 LJ71 is 19850-54071. It's identified as 12V-6V. The glow plug part number for your 97 2LT-II is probably 19850-54090 (before and early 97), but could be 19850-54120 (late 97 and on). Both of those are 12V-11V.

I agree with @saw. Do this:
Here in Norway its pretty common to swap from a 2l to the newer 2l 2, use 11V glowplugs and wire a wilson switch setup. I think thats the easiest way to make it function.
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If you want to by-pass it, go get a Ford Starter Relay (solenoid) and spring loaded switch from "Painless" and by-pass it.
Pretty easy set up, and the LJ has a hole already drilled for the switch below the steering wheel. Shouldn't take more than 2-3 hours.

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