B7100 Piston Installation

[Russell King]

You will have to rotate the engine numerous times to get the marks to come back into alignment.

While that may be what you want to do, would it just be easier to remove one of the gears and set the timing correctly per the manual?

Did you remove anything under the front cover or is it still set like when it was running? If you didn’t change anything the I assume it would still be correct unless there is a broken gear or something.

 

[torch]

Torch,

I did recheck the compression with the Schrader Valve you suggested and no difference.

Do you think my assumption about lining up the timing marks is correct?

Thanks, Larry.

I've not had the pleasure of doing this on a B7100, but if I understand correctly with #1 on TDC of compression stroke the crankshaft gear timing mark should be at 12:00, aligning with the idler gear timing mark at 6:00. The cam gear timing mark should be aligned with the idler gear tooth (not a mark) at about 7:30 and the injection pump gear timing mark should be aligned with an idler gear tooth at about 2:00 (not a mark).

Wolfman or one of the Kubota mechanics will jump in here if I have that wrong.

 

[Schmotown]

I've not had the pleasure of doing this on a B7100, but if I understand correctly with #1 on TDC of compression stroke the crankshaft gear timing mark should be at 12:00, aligning with the idler gear timing mark at 6:00. The cam gear timing mark should be aligned with the idler gear tooth (not a mark) at about 7:30 and the injection pump gear timing mark should be aligned with an idler gear tooth at about 2:00 (not a mark).

Wolfman or one of the Kubota mechanics will jump in here if I have that wrong.

Thanks for your reply. It looks like Russel has replied with the answer.

 

[Schmotown]

You will have to rotate the engine numerous times to get the marks to come back into alignment.

While that may be what you want to do, would it just be easier to remove one of the gears and set the timing correctly per the manual?

Did you remove anything under the front cover or is it still set like when it was running? If you didn’t change anything the I assume it would still be correct unless there is a broken gear or something.

Russell, you are correct on how to reset the timing and no, I haven't touched the gears inside the cover.

My goal was to recheck the gear timing because I am going to pull the engine for new liners due to my 300 psi compression readings after new parts.

If the original timing was "off" when I bought this tractor last fall that would also help explain my low compression. If it is off then I will reset the timing and reassemble the tractor and take new compression readings. If I can verify that the timing marks are correct then I am blaming the original liners and I will continue disassembling the engine to get it ready for new liners. Hope this better explains my plan.

Thanks, Larry.

 

[#40Fan]

After you get it to TDC, take some pics of the gears and post them.

 

[Schmotown]

After you get it to TDC, take some pics of the gears and post them.

OK.

 

[Schmotown]

OK.

#40 Fan, attached is a pic of the timing gears showing that the timing marks are correct. Piston is at TDC and the push rods were in the correct position for a piston that is at the top for the compression stroke.

Oddly, there is no timing mark on the front or the back of the gear on the crank. I'll order a new gear prior to reassembly so I can be sure that the timing is correct for the repaired engine. Hope this helps.

Regards, Larry.

 

[torch]

#40 Fan, attached is a pic of the timing gears showing that the timing marks are correct. Piston is at TDC and the push rods were in the correct position for a piston that is at the top for the compression stroke.

Oddly, there is no timing mark on the front or the back of the gear on the crank. I'll order a new gear prior to reassembly so I can be sure that the timing is correct for the repaired engine. Hope this helps.

Regards, Larry.

I think you forgot to attach the picture

 

[Schmotown]

I think you forgot to attach the picture

Oops!

 

[North Idaho Wolfman]

So you'll need to pull the crank gear and look at both sides closer as there will be a timing mark that is hiding.

 

[North Idaho Wolfman]

Note that the keyway on the crank will be down when it's set up properly.

You will need to remove the collar and the washer in front of the gear to see the timing mark.
Unless the gear has been installed backwards.

 

[#40Fan]

North, he mentioned there wasn't a mark on the back or front of the gear.

Schmo, do you have a work shop manual? I would think that you picture shows the correct orientation for everything, but I'm wondering if the manual states anything about where the woodruff key on the crank snout (if there is one) should be located when everything is in time. If there is one, where is it located in the picture you posted? 12 o'clock, 6, etc?

 

[North Idaho Wolfman]

North, he mentioned there wasn't a mark on the back or front of the gear.

Schmo, do you have a work shop manual? I would think that you picture shows the correct orientation for everything, but I'm wondering if the manual states anything about where the woodruff key on the crank snout (if there is one) should be located when everything is in time. If there is one, where is it located in the picture you posted? 12 o'clock, 6, etc?

Like i show in the pictures the mark hides till you remove the collar and washer, he hasn't done that.

And the keyway slot is about 6:45 to 7:00, so not a way to set the timing.

 

[North Idaho Wolfman]

You will need to pull the collar forward and the washer behind it forward to see the timing mark.