Do I have an exhaust water leak?

[britinusa]

We get about 1.25" of water with black particulate in the bilge after a 45 minute motor (ie. typically during the trip from the Ocean to the slip)

Today we pumped it out, about 1.75 gallons.

It's black, but does not appear to be particularly oily.

We dried out the bilge and did an initial clean up.
Also wiped down the sides of the aqua lift muffler plastic tank.

Then ran the engine at low to not so low revs for about 10 minutes.

No sign of the water leak from viewing under the aft berth or the head cupboard.

Plan is to check paper towel strips by the Aqua lift during the next trip.

Any suggestions to finding this leak much appreciated.

There is no One Hump tube just a regular exhaust tube from the riser to the aqualift.
No sign of water leak from the exhaust tube at the thru hull in the aft locker.

Paul

[britinusa]

Left the collected water in a jug overnight. After 24 hours, no oil floating on top, the particulates were not clumped but could be seen easily.

When I pumped out the bilge, I put the water in 2 jugs. The first jug was from the lower part of the water in the bilge, the second contained the remaining water. The first jug's contents were almost clear, the second was the nasty stuff.

Plan is to take the boat out for a motor on Friday and inspect it every few minutes looking for leaks.

Paul

[Ron Hill]

Paul : If there is no oil in that black water, I'll guess that you have a leak in the lower exhaust riser and/or the muffler.  Or the exhaust hose into or from the muffler??

A few thoughts

[Noah]

Whatever the case may be, while you are there, add a hump hose.

[KWKloeber]

Paul

Does your crankcase vent hose hang into the bilge, or go to the air intake?

kk

[britinusa]

Hmmm, Not sure, I'll inspect it tomorrow.

[KWKloeber]

Possible that blow by is tossing a lot of crap into / floating in the bilge?

ken

[britinusa]

got down to the boat today to measure for the Hump Hose.

I have ordered the 8" hose (existing hose is about 7" long)
Also ordered the engine to riser gasket & anti everything gooe.

forgot to look at the crankcase hose.

So either Sunday or Monday for that.

I keep my dremel on board so it should be easy (ha!) to cut out the hold hose.

Paul

[Stu Jackson]

Paul, some Tip & Tricks about some of the work you are about to do are in this recent Tech Notes article:  http://www.c34.org/mainsheet/html/2016/Muffler%20&%20Exhaust%20Riser%20Replacement.html

[britinusa]

Thanks Stu, I had not seen that article (probably did in the original Mainsheet article)

? - The nuts on the exhaust manifold appear to be new - Did you replace them or was that during an earlier project?

Any chance you have a link to repairing the muffler - just in case I find the need when I cut off the old input hose.

Paul

[KWKloeber]

Paul

I previously posted a PFD article from another who repairf a comprehensive repair on an aqualift.  It's on the techwiki - look under the engine topics.

Kk

[KWKloeber]

PS.  Evaluate your flange condition - you may want to have new studs at the ready. 

[Stu Jackson]

? - The nuts on the exhaust manifold appear to be new - Did you replace them or was that during an earlier project?

Any chance you have a link to repairing the muffler - just in case I find the need when I cut off the old input hose.

Paul, those are the original 1986 nuts on the studs.  I forget the thread, so if you need new nuts, take one off and go to a well stocked hardware store, make sure you get the right thread, fine or coarse.

Repairing the muffler shouldn't be necessary unless you really F-up the removal of the old hose.  Just use a box cutter and work slowly.  You may have to use a wire cutter to get the wire reinforcing off, but if you've gone that far, then the hose should come off.

You may be interested in this:  "What's in Your Muffler?"

http://c34.org/bbs/index.php/topic,6728.0.html

Ken's pointers and links are great, too.

[KWKloeber]

The studs are UNF thread on the nut end and UNC thread on the manifold end, and 2 different lengths.

See the parts manual on TW

Some have used red RTV on the exh gasket.  Not saying that's a good or bad idea, but if you do, make sure you don't  ooze any  into the water ports on the manifold.

kk

[britinusa]

Thanks Ken & Stu.
Those links say it all.

Will take lots of pics as I progress the hump hose install & muffler repair if found it's needed.

Paul