Is This Going To Work ?

[ButchPetty]

Please give me feedback.

[ndutton]

Yeah, like it. I'd like it better if the mixer was a little further downstream, about the height of the engine exhaust flange. I'd also like to see that last loop as high and as close to the boat's centerline as possible. Still like it though.

[ButchPetty]

Yeah, like it. I'd like it better if the mixer was a little further downstream, about the height of the engine exhaust flange. I'd also like to see that last loop as high and as close to the boat's centerline as possible.

The loop is very close to center line. Thanks.

[Kelly]

Watch out for salamanders and geckos when you put the exhaust piping together. They can clog the output and result in water backing-up into the cylinders.

[rigspelt]

Looks like you've been reading these:

http://www.abycinc.org/committees/P-01.pdf

http://www.boatus.com/goodoldboat/Marine_exhaust.asp

http://www.yachtsurvey.com/exhaust_risers.htm

http://www.yanmarhelp.com/i_exhaust.htm

The archives in this forum contain some very thoughtful threads on the topic, as it appears you have discovered.

Exhaust systems are tricky. I am certainly no expert, but for what my weak opinion is worth, I don't spot any trouble in the vertical heights you have chosen, and I like your efforts to eliminate bends as much as possible.

I took the insulation wrap past the injection point to cover all the metal of the dry/wet stack. Your diagram suggests you might be thinking of stopping at the injection point. No idea how important that might be.

I presume the waterlift muffler you pick will be large enough to collect water without risk of backflow to the engine. I did diameter/volume calculations to predict whether the MMI muffler was big enough using guesses about gas/water ratios, and in testing after installation on our boat we found that my prediction was right on: just over a safe inch after shutdown.

Try to avoid a dip in the last run of exhaust hose from transom loop to exhaust tip.

I installed a stainless steel Vetus exhaust tip in the transom that has a nifty little flap to minimize wave-splash backward into the exhaust hose.

I would have oriented the geckos with hot-coloured tails toward the manifold and cool noses toward the transom, but then I overthink things.

[ButchPetty]

Looks like you've been reading these:

http://www.abycinc.org/committees/P-01.pdf

http://www.boatus.com/goodoldboat/Marine_exhaust.asp

http://www.yachtsurvey.com/exhaust_risers.htm

http://www.yanmarhelp.com/i_exhaust.htm

The archives in this forum contain some very thoughtful threads on the topic, as it appears you have discovered.

Exhaust systems are tricky. I am certainly no expert, but for what my weak opinion is worth, I don't spot any trouble in the vertical heights you have chosen, and I like your efforts to eliminate bends as much as possible.

I took the insulation wrap past the injection point to cover all the metal of the dry/wet stack. Your diagram suggests you might be thinking of stopping at the injection point. No idea how important that might be.

I presume the waterlift muffler you pick will be large enough to collect water without risk of backflow to the engine. I did diameter/volume calculations to predict whether the MMI muffler was big enough using guesses about gas/water ratios, and in testing after installation on our boat we found that my prediction was right on: just over a safe inch after shutdown.

Try to avoid a dip in the last run of exhaust hose from transom loop to exhaust tip.

I installed a stainless steel Vetus exhaust tip in the transom that has a nifty little flap to minimize wave-splash backward into the exhaust hose.

I would have oriented the geckos with hot-coloured tails toward the manifold and cool noses toward the transom, but then I overthink things.

LOL, thats funny with the lizards. I dont know why I didnt think of it. LOL

I agree on the wrap....it wasnt drawn in but planned in.

I agree on the size of the muffler. This is my choice; http://www.fisheriessupply.com/produ...0035&cid=17456Also the rise of the hot pipe will be about 24 inches above the muffler as well.

Right now I have this crazy rubber "football" shaped thing in my system right before the transom opening. I have to take it off and try to figure out just what the hell it is. I think it is going away the flap idea is one I like also.

Thanks for the info and input.

[ButchPetty]

Watch out for salamanders and geckos when you put the exhaust piping together. They can clog the output and result in water backing-up into the cylinders.

Lmao

[ButchPetty]

Oh Crap !!!!!!

It just occurred to me that I have a 3-5 minute lapse time at initial startup when there is no water being injected into the exhaust system because of my Doyle thermostate......dont say I need to change it because I cant without changing the manifold and that ain't happening now.
Will the inline muffler....... http://www.fisheriessupply.com/produ...0035&cid=17456
......survive the assault?
Now I'm worried......I thought I had this problem solved.

[ndutton]

Whoa, whoa.

Doesn't your thermostat simply bypass the engine during warm-up and still deliver water to the exhaust? I'd be absolutely shocked if it didn't.

[hanleyclifford]

The in line muffler will survive about 35 seconds from cold start up. Find a way to inject some water with thermostat closed.

[ButchPetty]

Whoa, whoa.

Doesn't your thermostat simply bypass the engine during warm-up and still deliver water to the exhaust? I'd be absolutely shocked if it didn't.

Nope. No water till the engine reachs 140-150 degrees ......PERIOD. But after the initial days startup it gets water in 1-2 minutes.

[ndutton]

Nope. No water till the engine reachs 140-150 degrees ......PERIOD. But after the initial days startup it gets water in 1-2 minutes.

Oh my.

That also means there's no flow through the water pump as its discharge is closed off by the thermostat and we're talking 3 - 5 minutes, YIKES!!

Check this site for cooling system diagrams. A modification shouldn't be that difficult. And check your pump impeller, it's suffering too.

[ButchPetty]

Oh my.

That also means there's no flow through the water pump as its discharge is closed off by the thermostat and we're talking 3 - 5 minutes, YIKES!!

Check this site for cooling system diagrams. A modification shouldn't be that difficult. And check your pump impeller, it's suffering too.

Wrong. There is always water flowing thru the pump.

Wrong #2. I don't run impellers. Thats for whimps. I am strickly gear drivin.

[ButchPetty]

Hey, this is like one of those Jeopardy games......what engine am I?

Answer: What is a 1966 Universal Atomic 4, 100% marine.

I have a gear driven water pump. My thermostat allows such a minute amount of water pass.......like tears on the cheek of a lizard, just small amounts.

And the thermostat mount on the manifold is like none other than those that had Doyle thermos. It sucks......but yet it has advantages.....I think. :O

[ndutton]

Didn't realize you had a gear pump. I stand corrected.

Exhaust temps are still an issue.