Head Gasket Replacement on my Kubota

   / Head Gasket Replacement on my Kubota #1  

RobJ

Elite Member
Joined
Jul 10, 2005
Messages
3,486
Location
Spring, TX (Houston)
Tractor
Kubota L2500
Part 1...

After going throught some overheating problems this summer I bought a gasket set and decided to change out the head gasket this winter. Well it was time. I took some pictures to try and give you an idea of what's involved. So here Goes...

First couple is how I started. My tractor is pretty clean but I didn't want to heat it up by moving it for a pre wash. So I sort of blew it off and went at it. I set up a couple places to lay out stuff and place bolts and such.

First couple pics is with the side covers removed. I removed the top cowling, about 5 bolts....
 

Attachments

  • head-l-1.jpg
    head-l-1.jpg
    131.3 KB · Views: 4,744
  • head-r-1.jpg
    head-r-1.jpg
    123.8 KB · Views: 3,855
   / Head Gasket Replacement on my Kubota
  • Thread Starter
#2  
Next I just started removing the stuff in the way, muffler, air filter hose, made sure I had disconnected the battery, etc. Just working my way down.
 

Attachments

  • head-l-2.jpg
    head-l-2.jpg
    147.6 KB · Views: 5,284
  • head-r-2.jpg
    head-r-2.jpg
    135.8 KB · Views: 2,481
   / Head Gasket Replacement on my Kubota
  • Thread Starter
#3  
Next injection lines, wiring, other hoses, etc.
 

Attachments

  • head-l-3.jpg
    head-l-3.jpg
    140.3 KB · Views: 2,772
  • head-r-3.jpg
    head-r-3.jpg
    128.4 KB · Views: 2,341
   / Head Gasket Replacement on my Kubota
  • Thread Starter
#4  
Now I'm into the head. Remove the valve cover, rocker arms and lay them out on a nice surface. When I did this for a living I wasn't to concerned with keeping everything in the correct place. Since it's only a 3 cylinder I'm going to give it a go. I will keep the valves, etc in the proper places. Even though if I have them cut they all should be the same.
 

Attachments

  • head-l-4.jpg
    head-l-4.jpg
    141.7 KB · Views: 4,330
  • head-l-5.jpg
    head-l-5.jpg
    142.8 KB · Views: 3,345
   / Head Gasket Replacement on my Kubota
  • Thread Starter
#5  
another shot of the layout. You can see Kubota uses caps on top of the valve stems. If you don't watch for this you can move the head, knock them loose and chase them around the floor or down in the pan.

Then a shot of the head removed. I leave the manafolds on to aid me in grabbing something to lift it off. The head might weigh 50# or so??
 

Attachments

  • head-l-6.jpg
    head-l-6.jpg
    87.8 KB · Views: 3,931
  • head-l-7.jpg
    head-l-7.jpg
    126.8 KB · Views: 3,958
   / Head Gasket Replacement on my Kubota
  • Thread Starter
#6  
A look at the de headed block. I didn't see a block drain plug so I had some antifreeze. What I usually do is place a towel over the block, blow water into one of the jackets until the water line is well below the top of the block. No more water problems. After drying out the cylinders I spray in some wd-40 and work it out.

I was surprised to see more wear than I though at the top of the cylinder. I guess the previous owner wasn't as good at changing the air filter...usually the cause. Cylinder walls below looked fine.

The push rods do have lifters in the holes with the blue towel. They come out from the top and are basically just a cup with some drain holes. Pretty basic.
 

Attachments

  • head-l-8.jpg
    head-l-8.jpg
    147.5 KB · Views: 3,863
  • head-l-9.jpg
    head-l-9.jpg
    149.5 KB · Views: 5,931
   / Head Gasket Replacement on my Kubota
  • Thread Starter
#7  
I did see some areas of concern after I cleaned everything up. The rear cylinder (number 1 I'll call it since it's closest to the flywheel). On the back side the gasket showed some rust and slight pitting in the cylinder head. No coolant problems that I can see(no exhaust in the coolant).

I think you can clearly see in the pictures what I'm seeing.
 

Attachments

  • headgasket1.jpg
    headgasket1.jpg
    112.1 KB · Views: 3,537
  • headgasket2.jpg
    headgasket2.jpg
    129.8 KB · Views: 2,896
  • headgasket3.jpg
    headgasket3.jpg
    128 KB · Views: 2,515
  • headgasket4.jpg
    headgasket4.jpg
    121.9 KB · Views: 2,653
  • headgasket5.jpg
    headgasket5.jpg
    133.9 KB · Views: 2,694
   / Head Gasket Replacement on my Kubota
  • Thread Starter
#8  
After some closer looking, the intake valve in the #1 was also not sealing. I tried hand lapping the valve and could not get a clean contact. Maybe 25% is not sealing. I forgot to get a shot but will try and remember this afternoon. The others were not to bad and cleaned up with some lapping. But since I don't have the tools I used to have I'll have to take it in to a machine shop. When I was a mechanic, it'd take me about 10 minuted to do these 6 valves. Dangit!! I even checned on Ebay for a set. This set

eBay: ANTIQUE VAN DORN Automotive Valve Grinding Kit-Wood Box (item 300060691657 end time Jan-12-07 22:51:50 PST)

While older is simular to what we had. Its close since it may cost me about $1050-$200 to have it done. This will also include having the head surfaced just a bit. In the closeup you can see the pitting left by the gasket. I'd like to clean this up a bit.
 

Attachments

  • cylinder3.JPG
    cylinder3.JPG
    158.4 KB · Views: 3,695
  • head.JPG
    head.JPG
    163 KB · Views: 4,811
   / Head Gasket Replacement on my Kubota
  • Thread Starter
#9  
A few last general shots. Injectors, glow plugs, etc. The whole process to remove the head took about 45 minutes, no air tools on this one. Then about another 45-60 minutes to clean up and inspect. Again a little worse than I thought since the engine only has about 1300 hours on it.

It's off to the machine shop this afternoon to see what the damage will be. I'll probably get the "well you need new valves, guilds, blah blah. Wonder if I can rent the valve machine for 30 minutes. But he'll have to surface the head for me, my ROS sander is only good for clean up.

I'll update soon I hope...

Rob

BTW, has anyone else done this. With surfacing of the head, I'm concerned about clearances. The manual says .0217-.0276. Pretty tight and they want you to check with some plastagauge. .002-.003 should clear up what I need. I just don't want to push it or do it if Kubota says not to.

Thanks...
 

Attachments

  • injectors-glowplugs.JPG
    injectors-glowplugs.JPG
    144.6 KB · Views: 2,776
  • thermo.JPG
    thermo.JPG
    148.8 KB · Views: 2,852
  • tools.jpg
    tools.jpg
    139.8 KB · Views: 2,339
   / Head Gasket Replacement on my Kubota #10  
Rob, did you disassemble your engine without draining the antifreeze?
I did that as a kid and it cost me a totally rebuilt engine?
Jim:)
 
 
Top