B7100 leaking head gasket

Kenonf · Aug 23, 2014

Hi, I have a second series B7100 with 3000+ hours, and I am getting bubbles in radiator.
I did a quick search and did not find much. Can I get a few suggestions or some advise, I have not done a head removal yet.
It was over heated 7 plus years ago but the radiator has been overflowing for about 4 months.
That sounds bad but, it has not really been run much this summer maybe 20-30 hours with over flowing radiator.
I have a the shop manual, I just need to find it.
Thanks,
Ken

skyhook · Aug 24, 2014

Theres a stuff called Blue devil, check it out here....

Blue Devil Head Gasket Sealant Review

this may give you some relief, I heard it works well.

KennyV · Aug 24, 2014

Replacing the head gasket is Not a bad job, relatively easy...
it will prevent any additional damage that will happen as coolant is pushed into the oil and you will have the opportunity to adjust the valves as you finish the job...

Kenonf · Aug 25, 2014

The Head is off, the cylinder closest to the clutch #1? topped out at 300 PSI with out oil, and after a few cc of oil per the WSM it went up to 405psi. the #2 and #3 went to 400 psi clean.
I hope this it the one that is leaking. I used 15w 40 oil so I hope it plugged up the leak a little. The liner looked clean and smooth not sure what i should have been looking, for but I think i might have noticed any problems.
Off to engine shop on Tuesday to have the head inspected.

Now a few questions.
Should I replace intake and exhaust gaskets?
I am going to replace glow plugs, does anybody have a part number?
Should I replace the head bolts?
Should I put high temp anti-seize on exhaust manifold bolts?
The local diesel injector shop was going to charge me 60.00 a piece to test the old injectors about 10 years ago so I just replaced them for 70.00. I am going to take it to them when the head, both manifolds, dynamo, and radiator are back on so they could test the IP and check timing, is this a good idea?
Will the engine shop will tell me about my valves and if they need to be touched up?
I will post more soon as I speak to engine shop.
Ken

rbargeron · Aug 26, 2014

From the pics it looks like the middle cylinder might be leaking toward the coolant holes.

Intake and exhaust gaskets: if they clean up reasonably well, its ok to re-use them.
Same with head bolts - clean the threads with a wire brush so tightening torque is actual.
Thread lube or anti-seize is optional - temps are not that high on these engines.
If there were no symptoms of poor running, injectors are probably fine. How many hours on this rig?
A quick test of valves is with the head upside down pour a little fuel into one combustion chamber at a time and look in the ports to see if there is any seepage down the valve stems. Leakage would indicate worn seat or clearance in the guides, needing shop attention.

From the pics, if it were mine, I'd shine up the block and head surfaces, check the head for flatness in all directions with a good straight edge, and, if it looks ok, put it back together with a new gasket with permatex copper gasket spray. As further insurance pour a small bottle of Bars Leaks aluminum into the radiator before its full.

As always, prompt cheerful refund if advice is bogus. Dick B

Kenonf · Aug 26, 2014

Hey Dick, thanks for the info, What do you suggest I use to scrape the remaining gasket material of the cylinder body?
The machine shop has the head now, seems like the head has hardened injector shields, so I needed a shop that could grind instead of cut, if necessary to flatten it.
He could see where the leak was, between cylinders 2 and 3 from the discoloration on it.
I should get it back late this week or next week, and new head gasket from Kubota on next Wednesday.
Ken

rbargeron · Aug 26, 2014

Kenonf said:
...... What do you suggest I use to scrape the remaining gasket material of the cylinder body............

The cylinder block is iron and can be cleaned with a hardware store wire wheel driven by an electric drill. A 2" wheel or any size will work on a block - it's all one plane. Stuff some rags in the bores and anywhere the debris shouldn't get into.