Manifold & heat exchanger advice sought

[csmithers]

Hi Everyone,

I recently ran into a problem with my 1980 Westerbeke 30 hp diesel engine. I neglectfully did not replace my zinc in a while, and unfortunately the zinc corroded and broke off inside the heat exchanger. In addition, I have a bit of a coolant leak coming from the end cap of my heat exchanger. It's pretty bad, it's leaking even when the engine is not on.

So, I am seeking some advice from those that are more skilled than me with engines. To fix both problems I will have to take the exhaust manifold, heat exchanger, and mixing elbow off completely.

Does anyone have any tips? Beyond the obvious of removing the manifold bolts, changing the gasket, etc. Here are the things that I've thought of:
1) Use penetrating oil on the manifold bolts a few days and a few times in advance
2) Take the heat exchanger to a radiator shop to pressure test
3) Bleed the cooling system before running
4) Take before pictures of everything assembled
5) Label hoses

The full project steps I've written out here. Feel free to destroy it: http://bit.ly/11SvzsH

[colemj]

WAIT!

I don't have a picture of the W30 handy, but most zinc and endcap problems do not involve removing the exhaust manifold or mixing elbow.

Usually, you just remove the endcap and there is a gasket that seals it. With the endcap removed, you can access the broken off zinc. Most likely, if the zinc broke off, it is mostly used up anyway and whatever is left inside the heat exchanger will dissolve soon and go away.

But I don't understand why the manifold or exhaust elbow have to come off.

Mark

[colemj]

OK, so I just googled a picture of the W30 and it is like I thought. The heat exchanger endcaps are removed by simply unscrewing the bolt in the center of each endcap holding it against the heat exchanger. There is a rubber membrane gasket preventing leaking.

When you remove the endcap closest to the zinc fitting, you can access the zinc pieces that are loose in the exchanger (if any are still there - they will go out with the raw water). Change the rubber gasket on the leaking end.

Don't remove the manifold or elbow - no need for that at all.

Mark

[csmithers]

Thanks for the sanity check, it's pretty hard to get back there but I think you're right, it's better to start small and I think I was using a hammer two sizes too big :-) I'll cram my ass back there and see what I can do before I make this bigger than it should be.

Originally Posted by colemj

WAIT!

I don't have a picture of the W30 handy, but most zinc and endcap problems do not involve removing the exhaust manifold or mixing elbow.

Usually, you just remove the endcap and there is a gasket that seals it. With the endcap removed, you can access the broken off zinc. Most likely, if the zinc broke off, it is mostly used up anyway and whatever is left inside the heat exchanger will dissolve soon and go away.

But I don't understand why the manifold or exhaust elbow have to come off.

Mark

[marc2012]

The oem heat exchanger,on mine any way, had a rubber cap on the aft end with a hose clamp around it.I had to change clamps but finally,had to change hx.You really do not want to change it,REALLY BAD JOB.marc