2L-TE glow plugs. What should the resistance be on a health glow plug?

[EMTPrescue]

We are now down to -20C for over night temperatures and my Cruiser will not fire no matter how many times I cycle the glow plugs prior to cranking it.

The compression is healthy at 450lbs+ across the board and it has a newly remanufactured Fuel pump in it from Fred Holmes Fuel Injection in Richmond BC.

-10C seems to be the limit from a temperature standpoint to be able to reliably start the truck unassisted.

Oh and BTW, I have tested the glow plug buss and 12V there for about 15secs then down to 6V for about 30secs just the way it is supposed to work.

I also have two fully charged batteries at 675CCA so lots of battery on board.

I strongly suspect that I have one or more glow plugs either inoperative or at least perhaps only partially working.

I have read that some guys are able to get there trucks started reliably down to -20F.

Mine will not fire off much below than -10C which is a lot warmer than -20F.

 

[GTSSportCoupe]

You have to remove the glow rail to test them individually.

Resistance spec is 0.65 Ohms at 20C.

I bought Bosch Duraterm ones from Ebay UK and they work fantastic even in the low temps you're talking about.

You should be seeing more like 11V if the plugs are working properly. They draw so much current there is significant voltage drop in the wiring.

Sometimes the tips can break off in the cylinder head which really sucks. Work them slowly and carefully if/when you remove them. Turn them out a bit, back in a bit, out some more, etc.

In really cold weather you can do a couple glow cycles to get an easier start. Key on, wait 7 seconds, key off, wait 1 second. Key on, wait 7 seconds, then start. I listen for the glow relay to get the timing perfectg.

Hopefully you're running a 5w40 synth oil too.... (or similar 'winter' oil for easier starting).

 

[EMTPrescue]

I am aware of the current draw.
I was told by a mechanic that the circuit will draw the upwards of 80 amps in total which of course is 20 amps/plug.
What I need 2 know is what is the resistance in Ohms a healthy plug.

I want to measure that value at each plug to evaluate each plug individually before I start yanking them out a potentially breaking one that does not need to be removed.

You said, your's work fine "at the temos I was mentioning. I mentioned two temps. One was -10C where mine does start and then -20F where others have claimed there's will start. Which temp does your's start at?
Thanks

 

[Waikato Willy]

i went through all this with my KZJ78 , was a complete waste of time measuring them and testing, all the bench testing showed everything in spec however cold start was an issue, I just replaced them and the difference was noticed straight away, i stuck really cheapo ones in but we certainly dont get cold like you guys, lucky to get -5deg in winter

 

[GTSSportCoupe]

I am aware of the current draw.
I was told by a mechanic that the circuit will draw the upwards of 80 amps in total which of course is 20 amps/plug.
What I need 2 know is what is the resistance in Ohms a healthy plug.

I want to measure that value at each plug to evaluate each plug individually before I start yanking them out a potentially breaking one that does not need to be removed.

You said, your's work fine "at the temos I was mentioning. I mentioned two temps. One was -10C where mine does start and then -20F where others have claimed there's will start. Which temp does your's start at?
Thanks

You did see the resistance spec in my post above right?

My truck starts easy to about -10C with one glow cycle. From -10C to -20C it does fine with two glow cycles. I've only started it at -25C once, and that was not easy. That said, I had 15w40 in it at the time, and it was a damaged bottom end with poor compression in two cylinders. I think it would start easier now.

I did put a block heater in when I installed a good condition short block a couple years later.

 

[EMTPrescue]

I missed the resistance soec but have now read it. Thanks.
I will try the Bosch plugs.
I am amazed by how many stories there are on this and other forums on how heads have failed and bottom ends have failed on these and other Toyota 4 cylinder diesel engines.
So much them being bullet proof and running for 500K like some people think they will.
Anyways, thanks four the spec.
I am aware that they have to be disconnected from the buss to test each individually.

 

[GTSSportCoupe]

I missed the resistance soec but have now read it. Thanks.
I will try the Bosch plugs.
I am amazed by how many stories there are on this and other forums on how heads have failed and bottom ends have failed on these and other Toyota 4 cylinder diesel engines.
So much them being bullet proof and running for 500K like some people think they will.
Anyways, thanks four the spec.
I am aware that they have to be disconnected from the buss to test each individually.

The bottom ends are actually very well made and tough on these motors. They fail only through improper replacement of the cylinder head from what I've seen. These motors have a very high compression ratio (21:1), and the pistons are very close to the valves. You're supposed to measure piston protrusion (from block) very accurately, and pick the right thickness of head gasket so the piston clears the valves. Some people don't do this right, and use too thin a head gasket (Toyota sells many thicknesses). This causes the pistons to kiss the valves. Inevitably this leads to big end rod bearing failure from being repeatedly hammered. When I had my motor apart, I actually just bought the thickest gasket to avoid this issue.

In terms of the cylinder head problems, you should know that all Indirect Injection Diesels (IDI) with turbos run hot and are prone to problems. It's because the pre-combustion chamber is in the cylinder head, and is not thermally efficient like the combustion bowl in the piston of a Direct Injection (DI) Diesel. The four cylinder ones have a displacement disadvantage and are generally worked the hardest; so its no wonder they have more problems.

Generally speaking, IDI diesels are perfectly fine and last a long time in normally aspirated form. The turbo adds a lot of extra heat and related problems though. In the case of the 2LTE, Toyota added an emissions EGR system which suffocates the motor and exacerbates the situation even more. It's also a small motor put in big vehicles, so is generally constantly over worked.

Removing the emissions system (including the throttle plate) helps the motor stay clean and run much cooler. This coupled with a few other tweaks can help these motors run cool and well for a long time. Larger exhaust and an intercooler help tremendously. Also, running a cooler thermostat (82C) that the newer 2LTE came with also helps a lot.

There is a version of the 2LTE in Europe that is mechanically injected and has no emissions systems. It's called the 2LT-II. Case in point, it's known to be a reliable and long lasting motor there.

Toyota actually continued making the 2LTE until the early 2000's. They strengthened the cylinder head, and run a cooler thermostat. Those newer motors are known to be reliable. It's really just the early 90's ones that had some short comings (first rev cylinder head).

I like my 2LTE a lot. Runs excellent with good power after the changes I made.