Recursive Maintenance Continues

Maintenance recursiveness continues.

Being unable to budge the stubs left from grinding off the bolt heads, the only remedy was to remove the exhaust manifold/cooler to provide access for more drastic treatment of the bolt remainders than I could bring to bear with it in situ.

But...  before removing the exhaust manifold/cooler I had to drain both the antifreeze treated fresh water and the seawater from it.  This posed a problem because the genset and the heat pump share a thru hull, strainer and feed line.  Because it is still too cool here to do without the heat pump, I needed to install a shutoff valve in the genset seawater feed.

Genset seawater feed shutoff valve

This had it's own set of problems, first of which was a trip up into town to get some fittings.  Of course.  Despite the fact that I have a huge number of fittings aboard, none of them were suitable.  Then shut down the heat pump, close the seacock, cut the hose and clean up the mess from the drainage.  Finally, install the valve.

Draining the manifold/cooler

Now it was possible to drain the manifold.  Because Yanmar provided both drain petcocks and even drain hoses on the 2GMF, this was a clean job. 

And finally, removal of the now empty manifold was quite straightforward.

It turned out that the bolt stub removal was also easy...  because I took the manifold to Gustav at EngineTec here in Anacortes (highly recommended by Jason, and now I can add my enthusiastic recommendation as well).  An hour after I had dropped it off, Gustav called me telling me it was ready for pickup.  I barely had time to finish a post removal celebratory beer!

All I lack for reassembly is the gasket that goes between the manifold and the engine - currently on order.

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I lay the blame for this incident at the feet of Kohler, the genset manufacturer.  Kohler adapted the Yanmar 2GMF to power the generator.  When they did so, one of the changes they had to make (in addition to relocating the oil filter) was to reorient the exhaust elbow.  The Yanmar elbow points straight down - that would have interfered with the generator body.

Kohler tilted the elbow to the right

So Kohler cut the elbow pipe off the flange and rewelded it at an angle to clear the generator body.  So far, so good.

The problem was that they made a dog's breakfast of it.  When the pipe was rewelded to the flange, the flange warped, making a seal against the manifold completely impossible.  Rather than redoing the weld, perhaps on a fresh, heavier flange, Kohler sealed the 1/8" gap using JB Weld or something similar applied to the manifold, and then to make sure, they installed two gaskets.  This all became obvious when I was able to inspect the manifold, and when I removed the gaskets and exposed the JB Weld (or whatever) on the manifold flange.  This crappy jury rig held for a while... perhaps 400 engine hours.  And then the leakage started.

Yanmar: 1
Kohler:   0


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