L4150 Repair Restore

CiscoRanger

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I did a quick scan of the Kubota parts pages. There is no sign of a relief in that sectional valve or the outlet block. The only flow going out the tank return on the loader valve is exhaust oil from the cylinders. It seems very unlikely Kubota would have used that loader valve if the supply was not protected by a relief somewhere but I don't see one. However you have a shuttle shift model and the shuttle shift flow divider is ahead of the outlet block. That dumps a portion of the pump output flow which may be enough to limit pressure in the excess circuit.

Third function is just another valve inserted in the power beyond circuit coming off the loader valve. Any of the generic kits should work fine.

Dan



1665626827384.png
Thanks Dan. I’m gonna have to do some research on power beyond because I keep seeing that and don’t totally understand it. And probably some hydraulics in general too. Appreciate it.
 

CiscoRanger

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Thanks. Yeah, you have the purple and blue flows reversed. Would you happen to have the loader installation manual?
let me look and see what I have. I got a printed copy of the wsm With the tractor and I think it had the bf900 manual in it, but it’s pretty rough and some of it is illegible. If I don’t have one I’ll find one.
 

PoTreeBoy

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let me look and see what I have. I got a printed copy of the wsm With the tractor and I think it had the bf900 manual in it, but it’s pretty rough and some of it is illegible. If I don’t have one I’ll find one.
I'm just looking for some indication that the plug should be removed and replaced by a relief cartridge, or something like that.
 

CiscoRanger

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I did a quick scan of the Kubota parts pages. There is no sign of a relief in that sectional valve or the outlet block. The only flow going out the tank return on the loader valve is exhaust oil from the cylinders. It seems very unlikely Kubota would have used that loader valve if the supply was not protected by a relief somewhere but I don't see one. However you have a shuttle shift model and the shuttle shift flow divider is ahead of the outlet block. That dumps a portion of the pump output flow which may be enough to limit pressure in the excess circuit.

Third function is just another valve inserted in the power beyond circuit coming off the loader valve. Any of the generic kits should work fine.

Dan



1665626827384.png
Dan, I got this from the loader manual. If I am reading this right, The Junction block that goes to the loader looks to have a relief valve, and i guess flows right back into the trans case.

1665633922950.png
 

PoTreeBoy

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Dan, I got this from the loader manual. If I am reading this right, The Junction block that goes to the loader looks to have a relief valve, and i guess flows right back into the trans case.

View attachment 88687
So, is that junction block bolted to the transmission case so that the relief port, located on top of the figure, could dump back into the case?
 

Nicksacco

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Did you post some pics of the L35? Would love to see it. Also, did you paint it as part of the resto? I'm mulling this over right now. The L4150 is very faded on the orange, and has a lot of the Blue that is missing or needs to be re-done. I've read a few threads on it, and seems like it is similar to painting a car, vs just prep and a rattle can.
No I haven't posted pictures of the completed machine. I just completed it last week and now I'm waiting for the paint to fully cure before installing the decals. I think I only posted the rebuild of the Gear shift mechanism some time ago. It's a two-cable system.


I will post a few pics, however to answer your questions, I powder coated all of the linkages and controls and most of the brackets and supports. I painted the tractor with Kubota Orange II using a spray gun. I powder coated the pedals and painted them along with the Panel Frame and associated parts using Kubota Blue.

When I post, I'll give a description of what was done mechanically and such to round out the restoration effort. Suffice to say, it was not just a paint and go process! :D For example; I had to make a floor, rebuild fenders, and rebuild the entire electrical system/harnesses.

Now I'm reading your post with @PoTreeBoy 's info on 3rd function for a backhoe thumb and that may be another addition. I've been interested in that, but I wanted to get the darn thing finished and useful before adding more flames to the fire!

@PoTreeBoy It's great information and I've toyed with the ideas of a pedal or an electric button - hmmm, we'll see as time goes by.
 
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TheOldHokie

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Thats my guess.
If the block contains a relief mechanism that dumps into the tractor sump (Kubota's current design practice) there should be a visible plug of some sort in the block where the mechanism is installed.

1665657054743.png


I would bet a small sum of money that on a tractor of that vintage Kubota did not hook up a loader without providing a relief circuit somewhere.

Dan
 
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CiscoRanger

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No I haven't posted pictures of the completed machine. I just completed it last week and now I'm waiting for the paint to fully cure before installing the decals. I think I only posted the rebuild of the Gear shift mechanism some time ago. It's a two-cable system.


I will post a few pics, however to answer your questions, I powder coated all of the linkages and controls and most of the brackets and supports. I painted the tractor with Kubota Orange II using a spray gun. I powder coated the pedals and painted them along with the Panel Frame and associated parts using Kubota Blue.

When I post, I'll give a description of what was done mechanically and such to round out the restoration effort. Suffice to say, it was not just a paint and go process! :D For example; I had to make a floor, rebuild fenders, and rebuild the entire electrical system/harnesses.

Now I'm reading your post with @PoTreeBoy 's info on 3rd function for a backhoe thumb and that may be another addition. I've been interested in that, but I wanted to get the darn thing finished and useful before adding more flames to the fire!

@PoTreeBoy It's great information and I've toyed with the ideas of a pedal or an electric button - hmmm, we'll see as time goes by.
Fantastic, I can’t wait to see it!
 

CiscoRanger

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If the block contains a relief mechanism that dumps into the tractor sump (Kubota's current design practice) there should be a visible plug of some sort in the block where the mechanism is installed.

View attachment 88689

I would bet a small sum of money that on a tractor of that vintage Kubota did not hook up a loader without providing a relief circuit somewhere.

Dan
Dan / Po, was too late to go crawling under the tractor last night. I’ll go verify the plug here in a little bit. Thanks!

interesting given the torqued-down whine when the loader valve was dead-headed. I guess at idle that’s still a lot of pressure to overcome to get the RV open. But with it sitting empty for so long it also makes me wonder if it’s opening properly.
 

TheOldHokie

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Dan / Po, was too late to go crawling under the tractor last night. I’ll go verify the plug here in a little bit. Thanks!

interesting given the torqued-down whine when the loader valve was dead-headed. I guess at idle that’s still a lot of pressure to overcome to get the RV open. But with it sitting empty for so long it also makes me wonder if it’s opening properly.
Pressure gauge(s) answer a lot of questions. I consider them an essential tractor tool and especially so on an HST or power shift tractor.

Dan
 

CiscoRanger

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Pressure gauge(s) answer a lot of questions. I consider them an essential tractor tool and especially so on an HST or power shift tractor.

Dan
They do. And I have them. Just need to get the male pioneer end and fittings.

Speaking of, I'm not super pleased with how they didnt seem to work well on the shuttle valve. all the adapters have some sort of schrader type valve inside the adapter. I've never been a big fan of that, on my manifold gauges either. Seems sometimes the hose doesnt get screwed on tight enough to crack that valve, and throws the readings off. I dunno. Any issue with drilling out the adapters so the pressure flows straight through?
 
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rbargeron

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Quoting from PoTreeBoy's post back couple weeks ago : "I'm surprised noone who owns an L4150 has piped up. Seems like it'll make a capable utility tractor to me - 50 HP, hydraulic shuttle, independent PTO, loader, power steering, draft control."

I'm a bit embarrassed I've missed this whole thread - The L4150 was Kubota's push into the US market for 50 hp "compact" tractors. I got my first L345 in 1982, but when the L4150 came out in 1984 I was in love right away. Plenty of power and many little features that showed Kubota was serious about quality. I had my L4150 for several years before trading up to its successor - the L5450 - only traded up because I found one with an 11' backhoe.

Early in this thread I may have been able to offer some comments - but you've gotten great help from others. Reading through it I made a couple notes: The "orifice" on the shuttle valve is intended for dealer initial adjustment for buyer's climate - smallest for slow shifting, bigger for quicker. If set too far open in a hot climate, shifting is abrupt. Later versions of the shuttle have more cushioning. The welded and roll-pins on levers. etc. can break - but are often quickly fixed. I noticed both hydraulic pumps have been replaced (not blue) - looks like your checkbook escaped that.

When somebody on TBN or OTT says they have or are considering one of these "L3 " chassis models, (L3350, L3750, L4150, L4350, L4850, L5450) I'm often a cheerleader for them. Their build quality is really fine, compared to other brands. When this one is fully functional again it should be worth $15 to $17k - maybe more. It looks honest and original, not beaten. Your pictures of it are great - don't paint it.

Congratulations on an impressively quick learn on an unknown-to-you machine! It has had some unfortunately poor attention in its life, but its in good hands now. Take care, Dick B.
 
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CiscoRanger

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Quoting from PoTreeBoy's post back couple weeks ago : "I'm surprised noone who owns an L4150 has piped up. Seems like it'll make a capable utility tractor to me - 50 HP, hydraulic shuttle, independent PTO, loader, power steering, draft control."

I'm a bit embarrassed I've missed this whole thread - The L4150 was Kubota's push into the US market for 50 hp "compact" tractors. I got my first L345 in 1982, but when the L4150 came out in 1984 I was in love right away. Plenty of power and many little features that showed Kubota was serious about quality. I had my L4150 for several years before trading up to its successor - the L5450 - only traded up because I found one with an 11' backhoe.

Early in this thread I may have been able to offer some comments - but you've gotten great help from others. Reading through it I made a couple notes: The "orifice" on the shuttle valve is intended for dealer initial adjustment for buyer's climate - smallest for slow shifting, bigger for quicker. If set too far open in a hot climate, shifting is abrupt. Later versions of the shuttle have more cushioning. The welded and roll-pins on levers. etc. can break - but are often quickly fixed. I noticed both hydraulic pumps have been replaced (not blue) - looks like your checkbook escaped that.

When somebody on TBN or OTT says they have or are considering one of these "L3 " chassis models, (L3350, L3750, L4150, L4350, L4850, L5450) I'm often a cheerleader for them. Their build quality is really fine, compared to other brands. When this one is fully functional again it should be worth $15 to $17k - maybe more. It looks honest and original, not beaten. Your pictures of it are great - don't paint it.

Congratulations on an impressively quick learn on an unknown-to-you machine! It has had some unfortunately poor attention in its life, but its in good hands now. Take care, Dick B.
Dick, Thanks for those kind words and encouragement. The history on this tractor is fantastic, too. You might have missed the thread early on because it was named something like "Ports on side of transmission". And I only recently changed it to the current title.

Thanks also for the confirmation on the orifice 1 adjustment, it's nice to close that part out. I didn't mention it earlier on, but when I drove it a few feet back and forth, I tried it in both positions. There is a significant difference in the larger port for sure. Without the seat installed, it was very abrupt, almost like dumping the clutch on a car. The small side is much smoother, and it was 90F outside so that makes sense. I had considered adding a simple pull knob through the console to change it if I wanted to for winter. But I'm pretty far ahead of myself with thoughts like that. :ROFLMAO:

I'm happy to hear that you were pleased with the L4150 and felt like it was made well. I have to admit, I've already grown pretty attached to this tractor. Hope to hear more from you through this process.

- Phillip




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CiscoRanger

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@rbargeron Speaking of:

Do you happen to recall this triangle knob on your tractor?

1665688507562.png


I found something like it in the operators manual, but it shows under the shift lever, not in the current location on the dash.

1665688677568.png


1665688738432.png


There is the possibility I suppose that a previous owner just moved it there and the horn is missing, or something else. Been meaning to look at this but havent yet.
 

CiscoRanger

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Ok Po and Dan, I got a pic of the junction block. There’s hydraulic fluid under the tractor that I didn’t want to roll around in so this was the best pic I could take.

1665690247404.jpeg


it looks like the Relief valve block does bolt to the case, and the hex head is the top of the RV. This is view from the rear. The line coming at you is going to the 3ph
 

PoTreeBoy

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@rbargeron Speaking of:

Do you happen to recall this triangle knob on your tractor?

View attachment 88737

I found something like it in the operators manual, but it shows under the shift lever, not in the current location on the dash.

View attachment 88738

View attachment 88739

There is the possibility I suppose that a previous owner just moved it there and the horn is missing, or something else. Been meaning to look at this but havent yet.
Pretty sure there's no horn, they're not common on U.S. tractors.

edit: It's not unheard of for Kubota to make mid-run changes. Mine has turn signals that the early L35's apparently didn't, which moved the hazard lights off the combination switch to a separate switch. Not reflected in the WSM I bought, which should have been the latest.
 
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CiscoRanger

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Pretty sure there's no horn, they're not common on U.S. tractors.
I read somewhere it was an option...I'll have to find it...I dont remember if that is the location. I'm imagining, the fix-it guy pulled the safety off to get to the hydraulic shuttle under the dash, and then when they finally told him they were picking the tractor up, it was a mad dash to throw what parts he could find back on, any place they might go. :ROFLMAO:
 

PoTreeBoy

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Ok Po and Dan, I got a pic of the junction block. There’s hydraulic fluid under the tractor that I didn’t want to roll around in so this was the best pic I could take.

View attachment 88741

it looks like the Relief valve block does bolt to the case, and the hex head is the top of the RV. This is view from the rear. The line coming at you is going to the 3ph
OK, so your pump was protected. You might want to check its set pressure before you reinstall the loader.

I've been meaning to ask, how's that 5 cylinder sound?