Kubota B7100 Valve Adjustment Help Needed

[Hdoilcan]

So I changed out the head gasket on my b7100. Getting everything back together and need to adjust the valve clearance. Hope I’m getting all the terminally right. I understand how to actually adjust them with the feeler gauge. What I’m having a hard time with is understanding where to start. What cylinders are ? ? and ?? The manual says to adjust them in their injection order 1->2->3. Im not really sure I understand what the injection order means? How to know when and what piston is raised ect?
If I’m at the front of the tractor I will number the valve springs in order from 1-2-3-4-5-6. When 1 is compressed so is 6 and then when I turn the crankshaft (?) counter clockwise 4 and 5 will compressor and as I turn it again 2 and 3 will compress. If when 1 and 6 are compressed, what two do I adjust? If 4 and 5 are compressed, then what two do I adjust. And lastly if 2 and 3 are compressed what two do I adjust?
I watched what I could on YouTube but they don’t have a lot on 3 cylinders. Not any that were clear enough for me to understand anyways.
Any help would be great. This is all I have left before I see how I did on changing the head gasket. Almost time to fire her up.

 

[DwayneB]

May not be according to the book but, I always just watched till both valves were closed on a given cylinder and set the clearance. It's pretty easy to tell when the cylinder is coming up on the compression stroke by watching the valves.

 

[DLTTrekkers]

May not be according to the book but, I always just watched till both valves were closed on a given cylinder and set the clearance. It's pretty easy to tell when the cylinder is coming up on the compression stroke by watching the valves.

More simple way is to turn engine till a rocker has commpresed and released fully adjust that one...do as that one whit all of the rockers. Just remember that you work from a round shaft with a lope on it ...passing that lope and your good to adjust .

 

[npalen]

What is the easiest/best way turn the engine manually on these CUT's? (Never tried turning the engine manually on a small diesel)

 

[skipmarcy]

With a long handle 1/2" drive ratchet and socket on the crank pulley center bolt.

 

[npalen]

Thanks!
I suspect the valve lash has never been adjusted on my 1987 year B9200. Probably needs it badly.

 

[Dave M7040]

So I changed out the head gasket on my b7100. Getting everything back together and need to adjust the valve clearance. Hope I’m getting all the terminally right. I understand how to actually adjust them with the feeler gauge. What I’m having a hard time with is understanding where to start. What cylinders are ? ? and ?? The manual says to adjust them in their injection order 1->2->3. Im not really sure I understand what the injection order means? How to know when and what piston is raised ect?
If I’m at the front of the tractor I will number the valve springs in order from 1-2-3-4-5-6. When 1 is compressed so is 6 and then when I turn the crankshaft (?) counter clockwise 4 and 5 will compressor and as I turn it again 2 and 3 will compress. If when 1 and 6 are compressed, what two do I adjust? If 4 and 5 are compressed, then what two do I adjust. And lastly if 2 and 3 are compressed what two do I adjust?
I watched what I could on YouTube but they don’t have a lot on 3 cylinders. Not any that were clear enough for me to understand anyways.
Any help would be great. This is all I have left before I see how I did on changing the head gasket. Almost time to fire her up.

With your apparent level of knowledge, how did you first decide the head gasket needed changing, that there were no cracks in the head or block?
Did you have a WSM? were any of the gears on the front of the engine moved? Did you use a torque wrench?

If you downloaded the free one from kubotabooks.com you would find a lot of the information you are seeking plus have a valuable reference in terms of torque values for various fasteners.

Page 39 out of 355 will show you about setting valve clearances. The number for each cylinder position will also be there. Think of injection order as the same as firing order for a spark ignition engine.

The engine is a 4 stroke engine, i.e. the engine completes two complete revolutions for a cylinder to play its full role in running the engine. A movement of a connecting rod and piston, either up or down, equates to a stroke so if the engines revolves twice a piston moves up and down 4 times hence four stroke.

Producing an even delivery of power and with minimal vibration is part of the design process for the engine. Front cylinder will be #1.

I suggest you go to youtube and watch a number of videos on valve adjustment
This is one example of many.

Valve Adjustment on a Kubota - YouTube

Don't try and use the short cut method where you are jumping around from cylinder to cylinder to minimize the # of times the engine will have to be turned. For a beginner, this is just very confusing. Do both valves on one cylinder and then do the next.

Dave M7040

 

[ericm979]

Both valves in one cylinder will be closed for the compression stroke. Then the exhaust valve opens, then the intake. The best point in the four stroke cycle to set valve clearance is on the compression stroke. It'll be easier to turn the engine over if you remove the glow plugs or the fuel injectors.

You should feel some drag on the feeler gauge when pulling it between the top of the valve and the adjuster on the rocker arm. Not super tight where it's a struggle, not loose either. Check it again after you tighten up the lock nut. Don't be surprised if the clearance changes a bit. Keep at it until you're totally satisfied that the clearance is right.

 

[Hdoilcan]

I came on here and explained what was going on. I was told to take off the radiator cap and check for bubbles. If I found bubble coming up through then most likely a head gasket. Well I did have plenty of bubble. I had no coolant in the oil. I downloaded the WSM you mentioned and went with all recommended torque values. I took the head to a machine shop and had it tested. No leaks and not warped. I did not have the blocked tested.
I started her up yesterday and I still have some bubbles and overflowing into the blow off tube. It’s just not doing as much. I’m gonna pressure test the system as recommended and if I can’t figure it it from there then I’m gonna have to take it to the dealer.

Now that I understand how the four strokes work with the pistons going up and down etc....... very easy now lol.

With your apparent level of knowledge, how did you first decide the head gasket needed changing, that there were no cracks in the head or block?
Did you have a WSM? were any of the gears on the front of the engine moved? Did you use a torque wrench?

If you downloaded the free one from kubotabooks.com you would find a lot of the information you are seeking plus have a valuable reference in terms of torque values for various fasteners.

Page 39 out of 355 will show you about setting valve clearances. The number for each cylinder position will also be there. Think of injection order as the same as firing order for a spark ignition engine.

The engine is a 4 stroke engine, i.e. the engine completes two complete revolutions for a cylinder to play its full role in running the engine. A movement of a connecting rod and piston, either up or down, equates to a stroke so if the engines revolves twice a piston moves up and down 4 times hence four stroke.

Producing an even delivery of power and with minimal vibration is part of the design process for the engine. Front cylinder will be #1.

I suggest you go to youtube and watch a number of videos on valve adjustment
This is one example of many.

Valve Adjustment on a Kubota - YouTube

Don't try and use the short cut method where you are jumping around from cylinder to cylinder to minimize the # of times the engine will have to be turned. For a beginner, this is just very confusing. Do both valves on one cylinder and then do the next.

Dave M7040

 

[Dave M7040]

You did not mention if the head was checked for cracks?

Lets assume the problem lies with one of the cylinders but you don't know which one.

This technique I have read being used but have not tried it myself.

You tighten up the valve clearances on one cylinder so that the cylinder can never build up any pressure as it goes through the compression and firing strokes.

The engine will run very poorly as this cylinder with tight valves will not produce any power. What you are looking for is a change in the amount of bubbles you see in the rad.

You do one cylinder at a time. If you find one that has a marked reduction in bubbles, you at least now know what cylinder has the problem. Perhaps a crack in the block.

Don't overdo the negative valve adjustment as you don't want the valve(s) to hit the piston.

Alternatively, take an old glow plug and break it apart so you can get the guts out of it and then epoxy or weld an air hose fitting to the old GP. Use it to allow you to add pressure to each cylinder in turn with the engine off. Be careful as the air may cause the engine to rotate and pinch fingers.

Dave M7040