B7200HST with a D950 engine 1985 vintage. Does anyone know what the voltage should be from each glo plug to ground? The three plugs are parallel to each other and in series with the glo plug indicator. I wanted to remove the plugs for inspection but with this model and age, it appears you have to remove the intake manifold in order to remove the plugs. I'm hoping someone has a better way to remove them.
Glo Plugs
- Thread starter Berry
- Start date
I can't tell you how to remove them. I can tell you most glow plugs seem to run at 10.5 volts. If you get a reading of zero volts one or more of them is shorted. It would be harder to tell if one had gone open. For that you'd probably have to disconnect the wire and measure from there to ground with an ohmmeter.
GP's are typically tested by measuring the individual GP resistance to ground. Not certain of your particular GP, but most are in the 0.9 +/- 0.2 range.
If the manifold has to be removed, good or bad I'd change all three given they can be purchased relatively cheaply. Your local NAPA store may have them in stock.
If the manifold has to be removed, good or bad I'd change all three given they can be purchased relatively cheaply. Your local NAPA store may have them in stock.
Yeah I would definitely replace all, just hoping not to remove manifold. I would think Kubota would have considered that in the design. Hope they have changed for the newer models.
Thank you, will check volts again. I was only getting 7.5 volts before changing the glow plug indicator. The indicator had stopped glowing. Will have to wait for the rain to stop.
Russell King
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L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Remember the glow indicator is bypassed with the key in START but the GP's are still heating.
Measuring voltage to ground at a GP just tells you the wiring to the GP is OK but little else.
Remove the wiring on each GP and measure resistance to ground for each GP. Around .9 ohms means good.
The glow indicator depends upon current flowing to the GP's to heat.
One or two bad/open CP's means less current through the indicator and minimal to no glowing.
Dave
Measuring voltage to ground at a GP just tells you the wiring to the GP is OK but little else.
Remove the wiring on each GP and measure resistance to ground for each GP. Around .9 ohms means good.
The glow indicator depends upon current flowing to the GP's to heat.
One or two bad/open CP's means less current through the indicator and minimal to no glowing.
Dave
Just another thought.
If you meter can read amps, and if the wiring to the glow plugs can be removed (which would be necessary if you were to check the resistance of each independently) you could also measure the amps pulled by each glow plug.
Low amps would indicate a problem glow plug. Probably need a meter that can read a minimum of 15 amps to be on the safe side though. Current should drop as the plug heats up. Not sure what the steady state current would be for a hot plug, but it should be about the same for each good plug.
If you meter can read amps, and if the wiring to the glow plugs can be removed (which would be necessary if you were to check the resistance of each independently) you could also measure the amps pulled by each glow plug.
Low amps would indicate a problem glow plug. Probably need a meter that can read a minimum of 15 amps to be on the safe side though. Current should drop as the plug heats up. Not sure what the steady state current would be for a hot plug, but it should be about the same for each good plug.
The terminals on those glow resistors tend to corrode over time. That increases the resistance reducing the current. You will then have a greater voltage drop leaving less for the glow plugs. Many of those units can be easily disassembled and the terminals inside cleaned. They will likely soon corrode again. A better approach may be to just purchase a new glow resistor from eBay. That's what I did for my old Mitsubishi. I think it set me back $15, shipping included.
Yeah I know the glow plug indicators are hard to see at times. When I first picked the B7200 up I could hardly see it and I to would place hand over to feel the heat. At - 20 is hard to feel it at times. In the end I could see no glow at all on the indicator. This was the main reason for voltage test as I wasn't sure if I was getting a voltage drop across the indicator as it is a glorified resistor.., and looking for bad connections. I did remove the harness with the purpose of an individual test and to see if I could remove the plugs for an inspection which of I could I would replace. I have new ones on hand.
Thanks roadworthy, I have the new plugs on hand. I was hoping to find away to replace without having to remove the whole intake manifold. Unless I'm missing something it seams like a bad design that I'm sure they have improved on, mine being 1985 vintage.
I don't know if this helps or not but after my dad showed up with a B7200 HSTD on the rollback and said hop on and steer it off and you're gonna have to figure out how to get it started...it took me 6 months to figure out that there was such a thing called a "glow plug". LOL so once your able to stop chuckling long enough to read the rest of this, I can tell you what I did....and please do chuckle because I had plenty of good chuckles at myself learning how a diesel and hst function. I grew up on a salvage yard and can work on anything but a diesel...until now.
First thing i did was put power to the glow plugs from the battery. I used a test light to determine if all 3 were hot or not. Someone told me that glow plugs don't usually go bad and if they did then it isn't a good sign of other failures somewhere. After i figured that they were good, i knew it was electrical. Turns out after replacing fuses and checking wires, etc. it was the ignition switch terminals that were so packed with what appeared to be thick clay/mud that had dried that the terminals weren't getting spark. Same thing with the indicator. I cleaned them with a can of battery terminal cleaner i found at dad's yard and wire brush. The connectors were a bit more tricky and i ended up using Brake-leen for electrical components. It evaporates real good and didn't have any issues with residue or liquid i couldn't get to dry out. I put it all back together. Oh and also MAKE SURE YOU HAVE A HOT BATTERY or you will think you got issues when you really don't. You should've seen the party i gave myself when the indicator glowed bright and not only did she crank for me...after 6 months she frickin fired! Just my short story...maybe it helps or maybe it don't...either way...funny as hell wit an ending that i gives me a bit more to use when the boys think I need their help! HA!
cmorningstar01
Active member
Equipment
B7500HST LA302 FEL 5'Finish Mower B5100E 46" Snow Plow 22 ton splitter
I just replaced the glow plugs in my B5100, I could not get a socket in to take them out but I was able to use a 12mm combination open end/Box end wrench.
Before I replaced them it would take a good 30 seconds or more before the glow plug indicator would even start to glow a low orange red and the engine would cranks a bit before starting
With the new glow plugs in it takes less than 10 seconds and the indicator glows bright enough to see even when outside and the engine starts up a lot quicker.
after I took the old plugs out I resistance checked them against the new ones and there was a considerable difference(increase) in the resistance of the old plugs over the new plugs.
www.orangetractortalks.com
Before I replaced them it would take a good 30 seconds or more before the glow plug indicator would even start to glow a low orange red and the engine would cranks a bit before starting
With the new glow plugs in it takes less than 10 seconds and the indicator glows bright enough to see even when outside and the engine starts up a lot quicker.
after I took the old plugs out I resistance checked them against the new ones and there was a considerable difference(increase) in the resistance of the old plugs over the new plugs.
What a difference a new set of glow plugs makes
Tractor...late 1970's Kubota B5100E 2 cyl diesel ...one of my go to vehicles for dragging equipment,trailers,etc around the yard,plowing snow from my drive and yes I even had a 48" finish mower on it. I purchased it back in 2009 and put a new head gasket and glow plugs back then, It has served...
www.orangetractortalks.com
Well that all sounds just like a lot of fun, I wonder if the mud was the start of a hornets nest. I come from a long run in the Electric motor business and repaired all sorts of mechanical devices. Like you I have never worked on diesel engines or gas let alone HST. This is all new to me which makes it a great challenge.
With new glo plugs ready to change at any time if needed, I have changed my indicator and checked the ignition, oh and a new deep cycle battery, the glo now glos!! The old girl starts real good when she its warm out, the colder it gets the harder to start. I'm in eastern Ontario so not to cold yet, the minus 20s are coming. I'm not settled yet where the throttle should be on start up. It seems different as it gets colder.
Still experimenting having fun.
Good tip about the wrench, I will check after this storm passes by, no garage. I cant remember if I checked a wrench, definitely no socket. I have read that some say these older B seies takes a lot longer to preheat in the cold compared to the newer ones. I've also measured each one (wires disconnected) and they are about .9 Amos. Very comparable to the new ones I've bought.I just replaced the glow plugs in my B5100, I could not get a socket in to take them out but I was able to use a 12mm combination open end/Box end wrench.
Before I replaced them it would take a good 30 seconds or more before the glow plug indicator would even start to glow a low orange red and the engine would cranks a bit before starting
With the new glow plugs in it takes less than 10 seconds and the indicator glows bright enough to see even when outside and the engine starts up a lot quicker.
after I took the old plugs out I resistance checked them against the new ones and there was a considerable difference(increase) in the resistance of the old plugs over the new plugs.
What a difference a new set of glow plugs makes
Tractor...late 1970's Kubota B5100E 2 cyl diesel ...one of my go to vehicles for dragging equipment,trailers,etc around the yard,plowing snow from my drive and yes I even had a 48" finish mower on it. I purchased it back in 2009 and put a new head gasket and glow plugs back then, It has served...
cmorningstar01
Active member
Equipment
B7500HST LA302 FEL 5'Finish Mower B5100E 46" Snow Plow 22 ton splitter
I have an older B5100E and a newer B7500HST and the B7500 def starts quicker but once I changed the Glo Plugs the B5100E starts a lot quicker that it did previously.
Neglect. That is the only reason for the mud. I'm fortunate to have a father who has been a salvage yard owner since the late 60's. But my Kubo-gurl is picky and on a level of her own. She has taught me a lot and I too am enjoying the whole learning experience. I'm literally on day 3 attempting to remove the suction screens. Needless to say, I'm seriously being tested but I went to see dad last nite. Had to get some better tools that I know will work if they can survive the yard and my dad's temper! LOL keep up the good work! you aren't afraid of something new and complex and that's so awesome! hey, im proud of ya!