Glow plug questions

[handirifle]

I'm new to diesels so bear with me.

My MF1010 uses the ign switch left position to activate the GP's. I was told to hold there about 20-30 seconds. It seems lately that is not enough. Today it took about 4 tries, holding 20-30sec each time to get it started.

Do glow plugs wear out?

I assume they're replacable, and if so, what's the approx cost?

Does anything else keep them from top performance?

Thanks.

 

[1950T]

part number 3284128M1 $16.95 @ http://www.waltstractors.com/acatalog/copy_of_copy_of_starter.html i get some of my oliver parts from these guys. have got a few things for the 135mf there too

 

[irvingj]

Yes, glow plugs do "wear out." On my old Peugeot 504D, I'd change one or two about every 8 months or so. Easiest check is to disconnect the wiring harness from the plugs and do a resistance check, from tip of plug where wire connects to ground. They can fail other ways, but they seem to fail "open" --infinite resistance-- most.

So far, my MF's plugs seem to be holding up OK (165hrs).

 

[ray66v]

If your glow plugs are old, they could be dirty. Sometimes taking them out, and cleaning them, (about a 15 minute job), will allow them to heat better, and faster.

If they are really loaded with soot, they can be difficult to pull out of the head. Wiggle them back and forth, while pulling it out.

If it is warm where you are, you should need little, or no glow plug time to fire it up.

Have you tried different throttle settings?

Each engine has it's own quirks. Sometimes, if you set the throttle up from idle a little, before cranking, it will start faster.

I have one that starts best when I advance the throttle to full, and back to about 25% while I crank it.

 

[handirifle]

Cool great responses, thanks. Looking at the engine, I see three wires that look like smallish spark plug wires that are attached with nuts so I assume these are the glow plugs?

Ouch, $16.95 each, good thing there's only three of them. I'm gonna have to go back to work. (retired) I am in the middle of building my workshop and a covered patio for our spa, and those two projects are sucking the life from our checkbook. That plus the fact that this dummy (yours truly) bought the wrong size tires for the front and had to buy a second set to keep from screwing up his tractor, that all adds up.

The tire issue will be OK since I have a neighbor whose Kubota uses that size (6-12's) and I will give them to him. He has a ride on trencher and a big Case 580 backhoe he will be doing some work for me with (building a seasonal pond). Seeing how it costs me about $165 a day to rent a walk behind trencher, the $200 tire boo boo won't be so bad after all.

Back on track.
I was about to "pull the trigger" last night and order an I&T manual, but having heard they are not super complete, I hesitate. Would that give info like glow plug resistance values?

Would the I&T be a good "for the mean time" manual until I can save for a full blown factory one?

On the plugs, what would I use to clean them if, hopefully, that's all they need, a wire brush or some solvent?

As far as warm here, it's usually somewhere in the low seventies or later in the day, mid to upper eighties. Once the tractor has been started and running it doesn't need anything but turning the ign switch and cranking it over.

I will try the different settings. I understand that, as I have an old 83 Honda XL600R motorcycle, and it is FAMOUS for being cranky on startup, either warm or cold. "Pull in the compression release, pull choke lever to full choke, ign off, cycle the kick starter about 8-10 times (no kidding), then ign switch on, cycle kick starter to just past top of compression cycle, release compression release and give it a serious kick." Nearly everytime I get it started in one or two kicks even if it has sat for 2 months. The hot startup is identical except only 5 "pre-kicks". The thing runs like a scalded dog once it's started. Now THAT is a quirky starting engine.

OK I will check and maybe pull the glow plugs as soon as I can. Hopefully a cleaning will do. If not then, 1950T, thanks for the link.

 

[ray66v]

I don't know what the prescribed way to clean the glow plugs is. I have always wiped them with a shop rag until they were clean.

If it is warm outside, even a cold engine start should not take a lot of effort, with, or without glow plugs. That's why I am thinking you need to try changing the throttle setting, and verify if it is possibly a fuel issue.

Low compression, low fuel pressure, or dirty injectors can also cause starting problems.

 

[DEWFPO]

$16.95 each to me is cheap fix.

DEWFPO

 

[handirifle]

$16.95 each to me is cheap fix.

DEWFPO

If that was all I had going on and had a decent paycheck, it might be to me also, but right now it's a lot.

 

[handirifle]

Well, today I pulled the glow plugs, claened them and re-installed. No change, unfortunately. Weird cause this seemd to happen all at once. Sure seems to run the same once started too.

I measured the plugs, both in and out of the engine. My ohm meter is digital, and shows a reading of 1.0 with leads apart (open circuit), and 0.00 with leads touched (complete continuity). When I measure all three glow plugs, they measured out to 0.00, complete continuity. Are there other tests to see if everything is working? How can I be sure they are actually powering up?

If I turn the switch to the glow plug position, I should read 12V correct? I wonder if somehow, they are not even getting powered up?

 

[irvingj]

Not sure what you're saying.... With the plug wire disconnected, you should be able to get a reading from the tip of the plug to ground --anywhere on the block-- in ohms, or a "beep" if you're checking continuity. If you get an open reading or no "beep," plug is burned out. If plugs are out of the engine, you'd check between the tip and the threads of the body. Perhaps I'm misunderstanding- wouldn't be the first time!:laughing:

If this is what you're getting, a voltage check --or a test light-- at the plugs, with key in correct position, would be next.

IF your 1010 is similar to my GC, I just noticed there isn't a relay-- just comes right off the starter switch ("main switch") on a black & yellow wire, terminals # 19 and #30. (Mine is the same, manually hold in left position for glow plugs.) Wiring diagram doesn't show any fuse in that circuit, either.

Keep at it- looks like it might be a pretty simple circuit, again, if it's the same as my GC.:thumbsup:

 

[CubMon]

When you pulled the glow plugs, how did they look? - very much soot? Was the soot greasy or dry?

The best way to test a glow plug is with an amp meter in series with the power lead and compare readings between the three. The heater coils have such low resistance that the normal digital multimeter will only indicate that the heating coil is in tact. Rare that you would need all of the glow plugs at the same time......

Hard to believe that the ignition switch feeds all that current...most glow plug circuits go through a relay so that the switch only carries a small relay coil current.

Check your fuel filters. One of the first symptoms of dirty filters is hard starting.....the fuel to the injectors is 'wide open' at starting so any starvation would show up then and at the WOT position as well. Not many people run their engines all the way up against the governor so this condition shows up when cold starting.

 

[handirifle]

Cubmon
Thanks. I was looking at the engine yesterday, oddly enough, because after doing a major no-no, running it out of gas , I got to see it a lot closer. Thankfully I had read threads on this forum about how to get it started again, and after 15 min of cranking and bleeding, off she started. Whew!

Anyway, being totally new to diesels (not to engines and I have a fair understanding of how diesels work, fair) , I assume the 6" square box with the fuel lines coming out is the injector pump, and the filthy greasy hard to recognize blob next to it is most likely the fuel filter housing.

Doesn't look like it's been removed in years.

Does this filter go inside this unit or is it a spin on type affair? It LOOKS like a cartridge type filter.

Would a NAPA store handle these? There are no MF dealers anywhere in this area.

 

[handirifle]

I checked and NAPA does carry the filter and will pick one up. Tried it this AM with various throttle settings, andno difference. There is a ton of black smoke that comes out the exhaust when the throttle is wide open, and trying to start, so I'm betting the filter isn't the issue. I hosed the engine off and the filter actually looks fairly clean (I can actually see it now), but will change it anyway to be sure.

CubMon
How many amps should the glow plugs draw? I do have an Ampmeter, left over from my AC repairman days.

 

[CubMon]

I checked and NAPA does carry the filter and will pick one up. Tried it this AM with various throttle settings, andno difference. There is a ton of black smoke that comes out the exhaust when the throttle is wide open, and trying to start, so I'm betting the filter isn't the issue. I hosed the engine off and the filter actually looks fairly clean (I can actually see it now), but will change it anyway to be sure.

CubMon
How many amps should the glow plugs draw? I do have an Ampmeter, left over from my AC repairman days.

I'm not sure what they draw, but that's some data that is stated in your service manual though. I would make a current draw comparison between them....

I believe you're right about the filter not being the issue - black smoke when it starts and WOT - like an injector is dribbling fuel. That's probably the next check - the injectors. Sometimes you can remove them and reconnect the lines with the injector inverted to see what sort of pattern they spray. Other than that you could take them to a diesel repair shop have have them popped with a tester. If an injector is dirty, they'll stick and will also drip fuel into the chamber - that fuel is hard to ignite that is wetting the surfaces - the fuel needs to be atomized to a mist.

Was the soot on the glow plugs greasy wet?

 

[handirifle]

Yes it was sooty, not wet, although not super heavy. I am saving for a factory owners manual. At $183 , I don't have that much free cash. Retired!

 

[ray66v]

If the smoke on start up gets worse, when the cold weather gets here, it is the injectors.

You can try a large dose of a ULSD fuel approved injector cleaner.

Auto trans fluid always did a good job at cleaning diesel injectors, however, it is no longer recommended with ULSD fuel.

 

[CubMon]

Yes it was sooty, not wet, although not super heavy. I am saving for a factory owners manual. At $183 , I don't have that much free cash. Retired!

I feel for your situation...I can never retire. I started too late investing and then the crunch took what I had gained. I should have taken that union job way back when it was offered so that now the tax payers would be paying my way - easy street for union retired...

The owners manual shouldn't be that bad...you must mean the factory service manual. That would be good to have but a lot of info that you don't really need.

Have you looked at the air filter? I'm thinking about this rich start condition with black smoke and the revved up black smoke with the dry soot in the chamber. The engine appears healthy but just is either getting too much fuel or not enough air. Looks like at medium speed, the ratio is OK....

 

[handirifle]

Yup! Pulled it out this afternoon. FILTHY! I know better, should have looked at this first off. Will see in the morning how well it does. Got some "amazing oil" for the fuel injectors, supposed to clean em up. Will put that in the tank.

Went to pull the fuel filter filter out and fuel kept pouring from the tank. Does not appear to be a cutoff valve. So I tightened it back up till I get better light, to see if I am missing something.

 

[Transit]

As far as warm here, it's usually somewhere in the low seventies or later in the day, mid to upper eighties. Once the tractor has been started and running it doesn't need anything but turning the ign switch and cranking it over.

At 70-80 deg. F. you should not need to use any glow plug heat. Above 40 Deg. F. there should be enough compression heat to start the engine. Going by my engine, a plug will draw about 5 amps cold and as it heats up the current will drop to 1.5 amps each. You should also see the tip glow?

On the plugs, what would I use to clean them if, hopefully, that's all they need, a wire brush or some solvent?

This may come as a shock; the glow plugs are always ON. The heat from the last combustion cycle will keep the plugs glowing all the time and the plug tip should be hot enough to burn any soot off. Shock # 2, the engine is not a true Diesel but a Hot Bulb engine, the hot Bulb being the glow plug.

http://www.spiritus-temporis.com/hot-bulb-engine/hot-bulb-pseudo-diesel-development.html

 

[ray66v]

the plug tip should be hot enough to burn any soot off.

As engines get old, the world gets imperfect.