glow plug problems again

ncsawyer · January 18, 2016, 05:10:28 PM

I've got the 36 Yanmar on my LT40 and noticed today when I tried to start it (it was about 25 here this morning) that the glow plugs would only stay on 15 seconds and shut off by themselves. So I turned the key switch back off then right back on and the glow plugs came back on and again shut off by themselves after 15 seconds, almost like they are on a timer.

The last time I had glow plug issues, the glow plugs were staying on after the engine cranked. A new key switch solved that problem. Has anyone else had the same trouble? My mill only has about 80 hours.

ladylake · January 18, 2016, 05:30:07 PM

I don't think you should run the glow plugs more than 15 seconds when 25 above, the newer glow plugs heat up fast.. I wired in a separate spring loaded switch for my glow plugs, then I can run them as long and when I want. Steve

ncsawyer · January 18, 2016, 05:35:12 PM

Woodmizer recommendation is 30 sec when its below 32

beenthere · January 18, 2016, 05:55:43 PM

30 seconds seems like a very long time... but if WM says... :

My 32 hp Yanmar 3-cyl has heating element, not glo plugs, but starts with no heat down to 15° F. And below that I only heat for 5-8 seconds before start up. Always starts, but just less white smoke if I heat it up a bit first. Yesterday it started after setting out in -9° F. Been starting like that for 17 years now.

Kbeitz · January 18, 2016, 06:03:34 PM

I got two Kubotas.
One you turn the key switch backwards for a minute or longer then turn the key clockwise to start.
My other Kubota the glow plugs are automatic and only stay on about 5 seconds.
Sometimes I need to turn on and off the key twice to give the glow plug a double shot.
Both seem to do the job.

flatrock58 · January 18, 2016, 06:27:56 PM

I think the original relay in my Kubota 42 would stay on 11-12 seconds.

woodmills1 · January 18, 2016, 06:37:24 PM

my 62 cat on the LT 70 is hard to start cold. I am too far from the garage for a block heater. I don't even try below zero. If I need to run it cold I cycle the glow plugs three times to soak some heat into the head and put a shim in the throttle linkage, cause if it fires at idle it will stall. It was hard in warm weather also till I had the starter rebuilt, remember my machine sat for a few years before I got it.

drobertson · January 18, 2016, 07:13:04 PM

never had the glow plugs give any problems, but my 51 has a cold nature to it. this year even though mild so far she's been a pain in the twenties, I give some of the credit to a battery on the down hill slide, still a pain, hope you get yours figured out, I feel your frustrations,

MartyParsons · January 18, 2016, 09:50:13 PM

Hello,
I think if you look there are no glow plugs on the Yanmar. ( Yanmar Starter Aid Glow Plug #129008-77800 qty 1) It has one intake heater. The glow plugs or intake heater does have a timer, it will shut down when the starter in engaged or time out in 15 sec. If you need more time turn off and cycle the ignition switch. The timer was started with the Cat diesels. Early mills may not have this option.
Lombardini, Kubota and Cat ( Perkins) Diesel engines on Wood Mizer equipment do have glow plugs, these engines do use the same relay as the Yanmar with the intake heater.

I will check to make sure I am correct . I am positive the 47 hp Yanmar and the 55 hp do have the intake heater. Not sure 100% that the 35 hp has the intake heater.

On the Wood Mizer equipment there is a sticker on the control box that shows you the cycle time needed according to the outside temp.

I hope this helps.

I guess you know about starting fluid and glow plugs and intake heaters, Correct? smiley_fused_bomb

Marty

ncsawyer · January 19, 2016, 08:36:43 AM

Thanks Marty! My tractor has an intake manifold heater and I know that starting fluid is a no-no. It sounds like the relay is working correctly if it is supposed to time out after 15 seconds. If this is the case then my set up is working correctly.

It looks like my 35 yanmar does have glow plugs instead of the intake heater. There appears to be one glow plug for each cylinder and located right beside each injector.

4x4American · January 19, 2016, 06:11:00 PM

That's interesting... I didn't know that they timed out after 15 seconds, cause it seems like the light on the WM controls goes out after 30sec, or maybe I'm just impatient...I wonder if that's why it doesn't start so great in the cold? Maybe I should try to crank it after 15 seconds so it's still real hot, unless they did that for a reason, like to let the battery bounce back for a spell before cranking. Who knows..

drobertson · January 19, 2016, 06:39:15 PM

I'm going to throw this one out there, if the light on the display is on,, does this mean the glow plugs are all working?

ncsawyer · January 19, 2016, 07:26:36 PM

On mine as long as the light is on, it is sending power to the glow plugs according to my test light. But that still doesn't mean that the glow plugs are working.

MartyParsons · January 19, 2016, 08:26:05 PM

Hello,
If the console light is on that tells you the relay is on. Glow plugs may not be working, or the relay connection could be bad. You should always check to see you are getting power to the glow plugs, then remove the glow plugs and hot wire them to 12 volt. Please wear safety glasses if the glow plug stays on to long the can explode. You would hate to have a hot ember in your eye.
Do you have a Cat or a Yanmar. I dont have a 35 Hp Yanmar here I did check the manual for this engine and it said air heater qty one. ( Heater, Engine Glow #129100-77501 ) There is a 34 Cat and a 36 Cat both of these would have glow plugs.
?
Marty

woodmills1 · January 19, 2016, 08:33:24 PM

Marty you are the best.

ncsawyer · January 19, 2016, 10:46:22 PM

Marty,

According to the Yanmar model number on my engine 3TNV88 see below it should have glow plugs.

The picture below is of the glow plug in the cylinder at the rear of the engine. There is one for each cylinder. It has one wire going to that first glow plug. There is a thin piece of insulated metal that connects the first glow plug to other two.

According to the WM manual, the glow plugs should stay energized indefinitely until the engine is started, but mine cut off after about 15 seconds.

MartyParsons · January 20, 2016, 05:09:12 AM

Hello,
Well I think the manual is incorrect. There is no preheat location on the switch. I would say the writer was not sure what he was writing. ? Copying from a Yanmar manual? The glow plug relay WM has used since 1996 on most diesel engines, except for the 10 HP Yanmar LT15 and some of the other diesel engines on Twin blade edgers. The Edgers do have a turn left preheat on the ignition switch.
I does look like you have glow plugs on the 35 hp Yanmar. I learn every day. Thanks for posting the pictures!
Marty

ncsawyer · January 20, 2016, 09:22:07 AM

Thanks for info Marty! It sounds like the manual is indeed incorrect.

terrifictimbersllc · January 20, 2016, 09:25:53 AM

Just attach a dc meter to a glow plug terminal and to ground, hang it where you can see it from the key. Turn the key, see when the meter reads 12V or so, and for how long.