exhaust manifold

[Capn' Tony]

I'm starting to get ready for the season here on Cape Cod and went down yesterday to start on the raw water pumps. Got them off and ready in good time so then turned my attention to the inboard port enigine exhaust manifold.

On my last trip last year I ran that engine (Cummins 504 NA)pretty warm but not over heated. When I hauled her I saw that the first few inches of the exhust elbow were pretty well burned (i.e. paint peeled, metal discolored).

This prompted me to take off the exhaust manifold. I found lots of rust and metal debris from the raw water side just laying inside. What scares me more is the bolt under the last cylinder to aft came out very greasy right to the threads. The cylnder head port also had what seeemed like oil in it.

Not sure what all this means.
1. The rust and flacking metal in the manifold?
2. The dirty bolt (the rest were clean) and the traces on oil in the head port.


Did it possibly run with no water flow on that side? The outside bank of that engine is fine.
I have another manifold but hesitate to put it on after seeing the oil in that last clynder.

[Mitch]

Tony, I don't know alot about those old motors, but it sounds like your manifolds have just fallen victim to salt water. The wetness in that port could be, rings, valve guides or bad injector. Dave Crane is the local deisel guy. I could get his number if you'd like. What part of the Cape, I'm in Falmouth. Did you buy the old " Wild Goose " from Green Pond ?? Mitch

[Capn' Tony]

Mitch,
Thanks for your response. I think I used Dave many years ago when I first bought the Eliana. He is very knowledgeable and did me well. I have a spare 504 in the garage which I will use for parts. Since my post the other day I've engaged a local mechanic to take a look which should happen in the next few days. If I'm not satified and can't dig out Dave's number I'll let you know.

I bought her from Hyannis Yacht sales. I believe the previos owner used her on lake Erie. I have all the original paper work and invoice.
I hailed out of Chatam for a few years until I got tired of dealing with the cut (inlet). I then moved to Hyannis for almost 10 years now on the Bass River for the last 2.
Thanks Again
Capn' Tony

[AndreF]

Tony,
What year is your boat?
Mine, a '81, came w/504's.

[Capn' Tony]

Andre,

She's a '80 all original and been real good to me. Other than updating all the electronics and good basic maintenance she owes me nothing. In fact I owe her. I'm trying to get another year or so out of the clunkers before going for the gold on new engines.

You still running your 504's?

[AndreF]

Good for you.
Nah, previous owner put Cummins 6BTA's in in '93.

[Capn' Tony]

Well Andre I think we found part of the problem. A friend and I took a good hard look at the raw water mainfold and spotted a rather large hole betwen the fresh and raw water sides. It was right where the bolt passes through the mainfold. I think this explains my consumption of fresh water on extended trips and some white steam. I hope it has something to do with it running on the warm side too.

The spare manifold has been prepped, painted and will be installed upon reciept of fresh gaskets. Raw water impellers changed I'll let you know after splash.