Glow Plug timer

[FarmerGerald]

My TC33D is hard to start. Cranks and if the least bit cold--it has trouble starting--and I am in south Texas. Glow plug light comes on-and voltage to the glow plugs until the light goes out on dash. But, not sure how long the timer should keep voltage to the glow plugs. I thought I read that after the dash light goes out, there would still be current to the glow plugs for a few more seconds. Any feedback on how long the timer should supply current/voltage to the glow plugs would be appreciated. I used a stop watch and mine is only on for 3 seconds which seems short to me. Thanks in advance for help.

 

[PILOON]

As I understand it a cycle and it is completed when the light goes out.
Once it is out (completed) that is when you start.

Are you sure the plugs work?
You can check that by the fact that they will be noticeably warm to touch immediately after a cycle.

 

[FarmerGerald]

As I understand it a cycle and it is completed when the light goes out.
Once it is out (completed) that is when you start.

Are you sure the plugs work?
You can check that by the fact that they will be noticeably warm to touch immediately after a cycle.

Yes, in fact, just installed new plugs (wasted my money---but now have spares) tested old plugs and resistance is correct. Yes, they are getting warm. Yes they have 12 volts to them while the dash light is on. Yes -battery is charged. Only thing (other than a fuel issue) is that I think the voltage is not staying on long enough for the glow plugs to get hot. I am going to do a test with the old ones I removed and put voltage to them for different times and see how much difference a few more seconds make. I don't want to buy another timer if I don't have to--may consider doing what I saw someone else did with a direct electrical hook-up with a push button on the dash and hold it down (apply voltage) for several seconds. But, really wondering/concerned about how long the timer should keep voltage to the glow plugs. 3-4 seconds seems to me to be awful short time.
Thanks for your response.
Gerald

 

[Roadworthy]

The proper amount of time for a glow plug depends on the ambient temperature and the glow plug itself. Some glow plugs are designed to get very hot very quickly for short period heating cycle. Some plugs are designed for a longer duration. You may wish to begin by determining if you have the correct plugs in the first place - not like the ones you removed but the ones recommended for that application. For the correct plugs three seconds may be fine. Also investigate the proper duty cycle for your timer. From what I've seen most glow plugs don't run at twelve volts. I forget whether 9.5 or 10.5 is typical. My old Mitsubishi tractor has no timer other than my watch. I put a heavy duty spring loaded toggle switch (fifty amp) and its output goes through a glow indicator (dropping resistor) and from there to my (slow) glow plugs. When I got the tractor it had fast glow plugs wired direct to the switch. They didn't last long and neither did the switch. That's when I started doing glow plug research.

 

[Billrog]

Cycle them a couple times then try starting. I cycle them 3 or 4 times when starting my excavator when it's cold.

 

[ruffdog]

If I remember right, my tc33d would run the glow plugs about 10 seconds before the light went out. The timer didn't seem to change from summer to winter either.

 

[FarmerGerald]

If I remember right, my tc33d would run the glow plugs about 10 seconds before the light went out. The timer didn't seem to change from summer to winter either.

Thanks for all the tips/comments. I have tried cycling the glow plugs 2 or 3 times. This didn't seem to help. And I think I bought/installed the correct glow plugs for my tractor--used the part number from the dealer I contacted.
I think my next step is to "hot wire" to the glow plugs I removed--on my work bench and observe how they perform. I checked the resistance on all 3 removed plugs and they are all around 1.2 ohms which matched the resistance of the old plugs I removed. I am beginning to think wiring direct with a push button and counting seconds will be my solution--pending the test on the work bench.
Again, thanks for the help.
Gerald

 

[ruffdog]

My old parts book shows different glow plugs for the tc33 (#SBA185366060) and tc33d (#SBA185366190) models for some reason. The glow plug controller (#SBA385870300) is only showing for the tc33d model, not the tc33. So, does the D model use different glow plugs and needs a controller and the tc33 does not use a controller? Maybe the tc33 does not have a timer (controller) so you just count to ten? My RTV900 did not have a timer for the glow plugs either.

 

[thepumpguysc]

Even at 8-10 sec. I've had to cycle them several times in winter..
3 sec. is not long enough to get the plug warm, let alone the cylinder..
try it on a battery charger.. Neg.- to the body & pos.+ to the top..

 

[FarmerGerald]

Thanks for all the tips/comments. I have tried cycling the glow plugs 2 or 3 times. This didn't seem to help. And I think I bought/installed the correct glow plugs for my tractor--used the part number from the dealer I contacted.
I think my next step is to "hot wire" to the glow plugs I removed--on my work bench and observe how they perform. I checked the resistance on all 3 removed plugs and they are all around 1.2 ohms which matched the resistance of the old plugs I removed. I am beginning to think wiring direct with a push button and counting seconds will be my solution--pending the test on the work bench.
Again, thanks for the help.
Gerald

I think I have solved my mystery--using a 12 volt battery and jumper cable on my work bench--I find that it takes at least 7 seconds for a plug to start showing signs of glowing--and gets going good at 8+ seconds. Tried all 3 of my old glow plugs and the same on all. So, next task will be to figure out how to wire up direct to the glow plug wiring with a switch wired directly to the battery. Seems a lot more practical than buying another timer for ~$90 and the possibility of it still not staying on long enough to heat up the plugs. Again, thanks for the help.
Gerald