Kubota L35 Hard Starting When Cold
- Thread starter LeanGreenMan
- Start date
Okay, thank you for the explanation. After adjusting the valves, if there is no change, I will order a compression tester next. Surprisingly that is how it has sounded since I purchased it over 200 hours ago.
Haha I'm assuming you're talking about BlackHawk... we're up in Leadville.BTW, if you're by a certain mining/gambling town and want to get me a room at Century, I'll glad swing by and help. If you're on the other side of the mountain....that'd be a little to far for me.
I was thinking Cripple Creek. I just googled towns in CO with 9500 elevation and picked the closest to me. I didn't want to name the town just in case you wanted to keep your location slightly unidentifiable.
Compression tester for sure though. I'd confirm that it will work with your engine first. Most of them will use the glow plug hole, which is easier, but not all adapters fit. If you still have your old glow plugs, check the thread OD and pitch, plus room around where the plug screws in, to confirm what you buy will work.
Compression tester for sure though. I'd confirm that it will work with your engine first. Most of them will use the glow plug hole, which is easier, but not all adapters fit. If you still have your old glow plugs, check the thread OD and pitch, plus room around where the plug screws in, to confirm what you buy will work.
North Idaho Wolfman
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You can get an injection port adapter in easier than a glow plug adapter.
I think you have three / four / issues all causing your hard start issue.
You have low compression on 1 or more cylinder.
You have a fuel injector issue.
You have a glow plug control issue.
You have a battery voltage delivery issue (most likely high resistance on a cable or connection).
You are at high altitude.
Pull the injectors (keep them in order of where they came out.
Then do a compression test, That's going top give you the biggest answer as what to do next.
Then while the injectors are off I can tell you how to test them.
Have you tested the water temperature sensor resistance and the glow plug relay resistance?
Have you checked for a voltage drop on the battery cables and connections?
I think you have three / four / issues all causing your hard start issue.
You have low compression on 1 or more cylinder.
You have a fuel injector issue.
You have a glow plug control issue.
You have a battery voltage delivery issue (most likely high resistance on a cable or connection).
You are at high altitude.
Pull the injectors (keep them in order of where they came out.
Then do a compression test, That's going top give you the biggest answer as what to do next.
Then while the injectors are off I can tell you how to test them.
Have you tested the water temperature sensor resistance and the glow plug relay resistance?
Have you checked for a voltage drop on the battery cables and connections?
Okay, I now have the feeler gauge to check valve clearance. I plan to use the EO/IC method. Next up, Wolfman, I will pull the injectors.
First off, in case it helps anyone, I was able to get the top cover off by removing all the air intake system, glow plugs, and two of the injector lines. Its tight, but doable, without removing the fuel tank.
In the engines current position, 5 out of 6 rocker arms have play. I don't know if that is normal. (Up and down play, not side to side)
What I'm struggling with is how to turn the engine over by hand.... and also I want to make sure I am turning in the correct direction. Any tips for either?
First off, in case it helps anyone, I was able to get the top cover off by removing all the air intake system, glow plugs, and two of the injector lines. Its tight, but doable, without removing the fuel tank.
In the engines current position, 5 out of 6 rocker arms have play. I don't know if that is normal. (Up and down play, not side to side)
What I'm struggling with is how to turn the engine over by hand.... and also I want to make sure I am turning in the correct direction. Any tips for either?
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If you have the glow plugs or injectors out, it should turn over pretty easily. Maybe turn the fan, clockwise looking at it from the front.
Glow plugs are out, I did try turning the fan, but the belt is just spinning on the crank down below. I was hoping to be able to stick a socket on that, but it is a direct drive to one of the hydraulic pumps up front... maybe power steering, unsure.
You may need to tighten or replace the belt. I wouldn't try turning that front pump, there are 2 fiber disc couplings that seem kind of fragile. You could remove the starter and pry the flywheel teeth, it'll be a slow go.
If you're changing the belt anyway, you'll have to unbolt the couplings, so you might get a wrench on the crankshaft nose while you're in there.
That pump on the front powers the loader, backhoe, and 3ph. The pump on the side of the engine powers the steering and transmission functions.
Unfortunately that is exactly what I have been doing. I stuck a box end wrench on one of the bolts on the coupling and I have been turning the crank, and therefore the pump, by hand. I figure in small amounts that should be fine as it would be turned while the starter is cranking too?
I took all that apart about a year ago to replace the belt. Will try snugging it up, that would make it easier to turn.
I honestly don't understand what I need for the valves - placement. Per the manual it seems I need No 1 piston to be TDC. At that point, it appears I should be okay to adjust the intake on 1 and 3, and exhaust on 1 and 2. Then I need to get it to the "overlap position" and then I can adjust intake one 2, and exhaust on 3.
Unfortunately, I don't understand that at all.
As I'm trying to wrap my head around this, I assume I need to start on cylinder one (front), get either the exhaust or intake spring fully compressed. Once one spring is compressed, the other should be free, and I can adjust that valve. Then just continue moving on down the line, one rocker at a time.
Okay. Valves are all adjusted to 0.008 which falls right in the middle of the recommended range. I didn't check the looseness of any but the first one, which may have been the least loose, and that was in the 0.010-0.012 range.
I used what I believe is the EO/IC method. I turned the engine by hand until either the exhaust or the intake was fully depressed on each cylinder, and then adjusted either the exhaust or intake, depending on which one wasn't compressed.
I then cranked the engine over a couple times, by hand, and rechecked all clearances. All still sit at 0.008
If anyone thinks that sounds incorrect, please save me from myself.
Question. Do I need to bleed the injector lines after reassembly? Crank the engine over until fuel comes out, then tighten them down?
I still plan to pull the injectors and test, but I like to reassemble after each "fix" so I know what the culprit was.
I used what I believe is the EO/IC method. I turned the engine by hand until either the exhaust or the intake was fully depressed on each cylinder, and then adjusted either the exhaust or intake, depending on which one wasn't compressed.
I then cranked the engine over a couple times, by hand, and rechecked all clearances. All still sit at 0.008
If anyone thinks that sounds incorrect, please save me from myself.
Question. Do I need to bleed the injector lines after reassembly? Crank the engine over until fuel comes out, then tighten them down?
I still plan to pull the injectors and test, but I like to reassemble after each "fix" so I know what the culprit was.
Understood. Pretty sure this is mechanical like my 7.3 IDI, I'll bleed it to be safe.
Russell King
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L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
There may be an easy way to bleed the air out. It would be covered in the owners manual and the tractor would have an electric fuel lift pump. But I don’t know if that tractor has the easy way or not.
There is (probably) a vent at the fuel filter and another at the injection pump. You need to start at the fuel filter and then the injection pump and then the injector lines IF you ran it out of fuel. If you just removed the injectors then you just need to bleed the injector lines at the injectors.
There is (probably) a vent at the fuel filter and another at the injection pump. You need to start at the fuel filter and then the injection pump and then the injector lines IF you ran it out of fuel. If you just removed the injectors then you just need to bleed the injector lines at the injectors.
North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Yes you need to bleed the injector lines to the injectors.
I'm a little concerned that you were not able to spin the motor over by hand, you should have been able to.
Even with the pumps hooked up there is not back pressure from that system.
I'm a little concerned that you were not able to spin the motor over by hand, you should have been able to.
Even with the pumps hooked up there is not back pressure from that system.
Alright all. Another update.
First off, I can turn the engine over by hand with a box end wrench on those bolts that connect the crank to the front hydraulic pump. It's a 12mm wrench, so not a lot of leverage. Not hard to turn, with the glow plugs out of course. If that sounds wrong, please let me know.
Finally had time to reassemble today. Did such, but left the whole air cleaner assembly off so as to have easy access for bleeding the injector lines. I couldn't get it started, even after bleeding the injector lines (fuel coming out). Took everything back apart and checked my valve clearance again. Recommended range is 0.0072 to 0.0087. I set everything to .008, or thought I did. Upon taking it back apart, I realized that I didn't have the feeler "snug" enough, most we're sitting in the .009 to .010 range. Readjusted everything, now they are actually at 0.008. Engine still will not start.
Something I noticed while cranking is there sounds to be a "puff" sound coming out of the intake (or somewhere up front), once per revolution. No gasses evident. This may or may not have been there before, it is possible the sound is only evident at this moment as the air cleaner and intake is all off, which may have been muffling it before.
I did not notice any valves or rockers that were behaving oddly. All seemed to move up and down fine with the hand turning of the engine.
Thoughts?
First off, I can turn the engine over by hand with a box end wrench on those bolts that connect the crank to the front hydraulic pump. It's a 12mm wrench, so not a lot of leverage. Not hard to turn, with the glow plugs out of course. If that sounds wrong, please let me know.
Finally had time to reassemble today. Did such, but left the whole air cleaner assembly off so as to have easy access for bleeding the injector lines. I couldn't get it started, even after bleeding the injector lines (fuel coming out). Took everything back apart and checked my valve clearance again. Recommended range is 0.0072 to 0.0087. I set everything to .008, or thought I did. Upon taking it back apart, I realized that I didn't have the feeler "snug" enough, most we're sitting in the .009 to .010 range. Readjusted everything, now they are actually at 0.008. Engine still will not start.
Something I noticed while cranking is there sounds to be a "puff" sound coming out of the intake (or somewhere up front), once per revolution. No gasses evident. This may or may not have been there before, it is possible the sound is only evident at this moment as the air cleaner and intake is all off, which may have been muffling it before.
I did not notice any valves or rockers that were behaving oddly. All seemed to move up and down fine with the hand turning of the engine.
Thoughts?
Kubota L35 not starting
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Well, color me dumb. I assumed, as the injection lines are POST injection pump, that I wouldn't need to bleed anything before the lines. Opened the bleeder valve on the injection pump, cranked over the engine, and it started right up. Didn't even give it any throttle past idle.
I'm going to let it sit overnight, and then give it a try in the morning and see how it does. I'll report back on that. As quite a few of you suggested it was, this probably was a poorly adjusted valves issue. I apologize for taking a while to get to the valve adjustment, it was somewhat intimidating so I checked the easy pickings first.
My top cover is now leaking towards the rear, under the fuel tank. Naturally I forgot to order a new gasket for that. The current gasket is in surprisingly great shape and still pliable. I cleaned the mating surfaces before reinstalling, but it looks like I'll have to pull the top cover off again and either install a new gasket, lay a bead of RTV, or just do a better job of cleaning the surfaces and hope it doesn't leak.
I'm going to let it sit overnight, and then give it a try in the morning and see how it does. I'll report back on that. As quite a few of you suggested it was, this probably was a poorly adjusted valves issue. I apologize for taking a while to get to the valve adjustment, it was somewhat intimidating so I checked the easy pickings first.
My top cover is now leaking towards the rear, under the fuel tank. Naturally I forgot to order a new gasket for that. The current gasket is in surprisingly great shape and still pliable. I cleaned the mating surfaces before reinstalling, but it looks like I'll have to pull the top cover off again and either install a new gasket, lay a bead of RTV, or just do a better job of cleaning the surfaces and hope it doesn't leak.
Russell King
Well-known member
Lifetime Member
Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
There are materials to apply that should help stop that leak.
Look at Hylomar products.
hylomar.com
They are something akin to a grease like substance that hold up to petroleum products and heat to seal contact surfaces. They are usually applied to metal to metal surfaces but some of the products can be used with gasketed surfaces also (as far as I remember).
There are other products that are similar, I just use Hylomar and can’t remember the other brands.
And don’t forget to close the bleeder valve if you didn’t do that already.
Look at Hylomar products.
Non-Setting Compounds Archives - Hylomar
The original product was developed in conjunction with Rolls-Royce and was used for sealing aircraft engines. Engine, Electric Motor, Gearbox, defence industry and many other original equipment manufacturers choose Hylomar
hylomar.com
They are something akin to a grease like substance that hold up to petroleum products and heat to seal contact surfaces. They are usually applied to metal to metal surfaces but some of the products can be used with gasketed surfaces also (as far as I remember).
There are other products that are similar, I just use Hylomar and can’t remember the other brands.
And don’t forget to close the bleeder valve if you didn’t do that already.
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If you apply sealer, keep it very very thin. Not a big blob that is then squeezed inside the cover, possibly breaking off and causing havoc.