Waterlift exhaust system question

[Mike Thomas]

I am replacing my old water jacket type of muffler with a Water lift muffler in my 76 E-29. I have piped the exhaust in the same configuration as the water jacket and will locate the Water Lift muffler in the port cockpit locker. The muffler will sit at about the waterline. I have piped the exhaust well above the waterline before the muffler and can do the same with exhaust after the muffler but I am wondering if that makes sense. My thinking is that if I'm having a problem starting, I will still be pumping water into muffler as it cranks and never build up enough exhaust pressure to blow the water out. I would think that I don’t want an exhaust system where the "in" (engine side) of the muffler is lower than the “out” side of the muffler. In theory, if I kept cranking and never started, I would fill up the muffler then exhaust manifold before the water started to pump out of the exhaust port.

The interesting thing is that I’ve never seen this issue ever addresses. All of the diagrams that I have seen show what I think is a bad design (if the engine doesn’t start). One article mentioned that there is a drain plug that can be opened in the event of hard starting but that would be difficult.

I would think that the only reason for having the “out” side of the muffler piped higher than the “in” (engine) side, is to keep a following sea from getting in the engine but if the “in” side of the muffler is piped higher than the “out” exhaust port, that should not be a problem.

Am I thinking correctly here?

Mike Thomas
E-29 Babylon NY

 

[Guy Stevens]

physics on water lift mufflers

The reason that the out is higher than the in is so that the gases push the water out of the muffler..... This is what makes the whole thing work. Teh gas pushing out the water cools and quiets the gas as it goes out of the muffler. The out tube actually sticks down inside the muffler so that the water is above it most of the time, then the pressure builds up forcing the water out of the out fitting and through the tube.

Yes if cranked WITH THE SEACOCK OPEN for an extended period you would flood the water lift style muffler and back flood the exhaust valves on the engine.... I have seen it happen before, but it is rare.

So if you have to crank and crank on a boat, you need to find another way of figuring out what is wrong with the engine. They should start rapidly, within a couple of rotations unless something is wrong. If extended cranking is necessary, then you should close the seacock. (Although this is hard on the impeller in the raw water pump.)

You can have the engine output higher than the overboard discharge of the muffler. There should be a drawing of that on the same site you got the other drawings....

Guy

 

[hodo]

water lifts

Mike, make sure to size the waterlift correctly. it needs to have the capacity to hold the water that is in the exhaust between the gooseneck, and the exhaust manifold after shutdown. Otherwise, it could back fill the engine. I think they figure there is a 20 to 40 % ratio of water to exhaust. In other words, what is in the running system is 20-40% water, and the rest would be exhaust. While you are there, make sure the water flow is wide open from the fitting in the exhaust riser through the mixing chamber. Harold

 

[chaco]

Wet Exhaust Made Simple

Have just replaced the entire Wet Exhaust System on E35II.
Used 1 1/2" Galvanized Iron fittings and Exhaust Hose (with wire !)
Check out www.centekindustries.com for Vernalift Installation.
You will need to Gooseneck at your engine exhaust outlet to above inlet
to Exhaust Lift Station (can).The water injection MUST drain back to your
can by gravity to clear piping when engine is stopped. The cooling water
flows from the pump outlet to ABOVE the waterline with a vacuum breaker,
then down to the injection port. Follow the Vernalift diagram and you can't
go wrong. You STILL need to start IMMDEDIATELY or your system will be
pumped full of water (typical for engines below waterline). As you have
starting problems...shut off water inlet....start engine....open inlet......
FIX STARTING PROBLEM :nerd:
Also check out the Engine Installation Manual in www.westerbeke.com

Happy Wet Exhaust

 

[gareth harris]

Chaco - is your engine in the cabin centre or under the steps? If it is the cabin, could you post some pictures of your set up? I need to do the same, but the only way to get the water lift at the bottom point of the system would seem to be to cut a hole in the sole aft of the engine.

Gareth
Freyja E35 #241 1972

 

[EGregerson]

muffler

I've seen a couple of catalina 30's with a shut off valve for this very reason. One could (almost ) as easily just shut off the thru hull intake. But I'm with Guy on this; if you crank away for a period of time, you'll likely wear down the batteries or burn up your starter motor. Best thing is check the fuel supply and pull the multimeter.

 

[Mike Thomas]

Everyone,

Thanks for the advice.

In as far as all of your questions? The engine is a gas Atomic 4 with the water outlet coming out of the exhaust manifold so I shouldn’t need a new water jacket. The engine is under the companionway but at the lowest point of the hull so I will have to mount the muffler off to the stbd side at about the water line.

I'll probably go with leaving the "out" side of the muffler an inch or two lower than the "in" side. It seems logical and I’m still dealing with a fluid that want’s to seek it's own level, so I should be fine.

I've also learned that 99% of the time, if Guy thinks its OK, then it's OK.
Don't bother to ask about the 1%, it hasn’t happened yet.... Thanks Guy..

I'll post some pictures when it's finished.

Mike T
E-29

 

[chaco]

E35II Wet Exhaust

Gareth....

Find attached pics. The Lift Station (can) is located in front of the fuel tank.
The gooseneck rises above the can, injection port on the drop and exhaust
hose runs back under the settee, crosses the nav station (with 3'' sleeve)
runs back under the quarter bearth and in to can. This system DRAINS back
to the can at lowest point. The original system formed a P-Trap for the wet
exhaust that had to pump back up to the can. The PO RUINED a perfectly
good M4-30 with cooling water flow in to the engine exhaust outlet.
Cooling water mixed with oil and sat in the oil pan for YEARS
I followed the Vernalift Installation Manual to the letter, because they KNOW
Wet Exhaust Systems

Happy Wet Exhaust

 

[gareth harris]

The key to your set up is running the exhaust through the berth rather than through the bilge - I thank you deeply since I had not thought of it myself. Does the hose get warm enough to worry about what rests against it?

Gareth
Freyja E35 #241 1972

 

[chaco]

Exhaust Hose Conduit

Use 3" Exhaust hose as Conduit in exposed area and through Bulkheads for
heat / chafe guard. The engine cooling outlet runs at 150/160F. Doesn't get
above 110/120F at thru-hull outlet. The Conduit is for Safety and Chafe Guard
The System works great and quiet as a mouse
The Mid-Engine Exhaust Systems were NEVER installed correctly and are a
potential source of problems for all E35II owners
Will publish project completion pics :nerd:

Happy Wet Exhaust

 

[chaco]

E35II Exhaust Project

Here are some Exhaust Project completion pics :nerd:

Happy Wet Exhaust