B7100 minimum head gasket parts and repair manual?

[idosubaru]

Saw lots of HG posts but not about parts or process.

Headgasket, intake and exhaust manifold gaskets. Anything else?

I’ll ask the local dealer but are the repair manuals/head gasket process online ?

I’ve owned this for 10 years and had a nagging coolant loss for the last two years new radiator and cap and hoses and still using coolant. So I’ll pull the heads.

 

[North Idaho Wolfman]

You can get the service manual at Kubotabooks.com.

I woulds suggest spending the little extra and get 100% Genuine Kubota gaskets.

And don't forget the O-ring for the oil feed tube.

 

[Jim L.]

I am not familiar with the B7100 but will try to help based on my limited experience with a different model.

Definitely need a Workshop Manual and illustrated parts list. Some of the numbers on parts will change and you will need to cross-reference up to those.

I believe that on your model the head gasket also has a shim. You may need a gasket for the muffler if you remove it. The intake manifold and exhaust manifold may or may not need to be removed. Also water cooling. Cover has a gasket.

You may get lucky and find the problem is only the gasket/shim. Plan on some work getting the block and head clean, really clean, for the new gasket. Do not use wire brush, brillo pads, starbrite pads, anything hard or that will abrade off material that will fall into block. Brass wire brush is OK but chemical works best to clean surface. Plastic scraper not metal. Finish taking off chemical with brake cleaner, not getting any down into block.

Plan on oiling tappets before re-assembling engine. Small tube of assembly lube. CALIBRATED torque wrench for head bolts (and oiled bolts).

it's possible that you have small crack in head, typically at exhaust valve seat. You may think about cleaning head and applying crack detector. Or take to shop for pressure test. In that case, more gaskets will be needed, new valve seals. Valves must go into original places, same as tappets and lift rods.

Reset valve clearance in any case after new gasket.

Lots of brake cleaner, electronic cleaner, solvent for carbon build-up, shop rags, cardboard for parts and marks-a-lot to organize parts, painters tape to mask hoses and tubes and electric connectors.

If you remove the injectors you will need new gaskets for the injectors.

Difficult to say what you will need until you look into head. If coolant leak, then you may have scale build-up. Take pictures.

Plan on having the machine down for awhile if you need to order parts, and you will.

 

[idosubaru]

Thanks. I***8217;ll use OEM parts have the heads pressure tested.

Maybe the dealer will have a general idea on necessary parts? My dealer is an hour away.

Ill dig in and see what I find. I***8217;ve done lots of automotive head work so I have the tools the general idea and proper surface prep.

 

[Jim L.]

Great that you have experience.

An option that would save you 4 hours of driving would be to order from Messicks. They have parts diagrams on-line. An upper gasket kit would have the gaskets under one part number. Doubt that it includes the injector gaskets. But again, the WSM and illustrated parts diagrams will get you there.

 

[North Idaho Wolfman]

Printed Parts manuals are out of date, go straight to Kubota.

http://apps.kubotausa.com/illustrated-parts/

Sorry Jim , I'll have to disagree with you on several points.

You do not need the shim unless you need to shave the head.
The heads crack between the valves and the prechamber.
Kubota does not have a "upper Gasket kit" you'll have to buy all the parts individually.
The tappets do not get oiled or even taken out of the engine, they are solid lifters and down in the engine.
And what would he use electronics cleaner for?

 

[D2Cat]

idosubaru, welcome to the forum. Your task just got easier, you only have one head!

And the little things, like North Idaho Wolfman mentioned, don't overlook the O-ring that is on the back/left side of the head. It's easy to miss.

 

[Jim L.]

Wolfman has the real experience on this subject, I plead total ignorance on a B7100 shim.

I agree on cracks between the valve seat(s) and prechamber.

I totally misread the B7100 upper gasket kit from the parts diagram.

Same with tappets.

Electronics cleaner for electrical connectors and plastic parts where brake cleaner may be too harsh. On my machine, flushes out a lot of dirt.

Thanks for keeping it straight.

 

[D2Cat]

Under each rocker arm is a "spacer". I think it is there to reduce wear. They are about the size of a 357 battery. Keep them is a safe place. When you assemble the valve train be sure to put them back, or you'll never get the valves adjusted!!

 

[idosubaru]

Under each rocker arm is a "spacer".

Thanks! Probably be obvious once I get the parts diagram/manual/valve cover off but:

1. Is valve disassembly required to pull the heads or to resurface?

2. Do the spacers need to retain orientation - an “up” and “down”? I will retain that and keep the same face contacting the same surface but I prefer knowing the facts behind what I’m doing!

 

[idosubaru]

idosubaru, welcome to the forum. Your task just got easier, you only have one head!

And the little things, like North Idaho Wolfman mentioned, don't overlook the O-ring that is on the back/left side of the head. It's easy to miss.

Thanks I’ll add the oring - headgasket, intake and exhaust manifold gaskets and oil oring.

Ha! clever reference to head count - it looked easy at first glance but I was timid that I was oversimplifying what I was seeing ! Doesn’t sound too bad so far.