Dry exhaust / reversion question
04-01-2019 | 05:07 PM
#1
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From: belfair, wa
Dry exhaust / reversion question
I have a 502 with standard height stainless marine exhaust manifolds and risers. I fired up the motor for the first time. New motor. Let it run a couple minutes and pulled the risers off and there was a little bit of water down there. I was wonder if on the hose that runs from the manifold to front of the riser was to be bypassed and i run the hose out the back of the boat instead. Pretty much making it dry exhaust. My question is beside being a little louder would it creat to much heat in the engine compartment? Not have the water running through the risers. Any other issues? Anybody else done this?
04-01-2019 | 05:39 PM
#3
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From: belfair, wa
OK, SO HOW ARE THE DRY PIPE DIFFERENT? MADE FROM DIFFERENT MATERIAL. THESE DO EXIT AT THE TAIL END OF THE RISER. BUT STILL GETTING REVERSION. WAS GUNNA BUY SOME TALLER RISERS. THE 500hp VERSION BUT WAS JUST WONDERING ABOUT THIS OTHER OPTION.
04-01-2019 | 05:56 PM
#4
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From: SF Bay Area
Just checking to see if your running on the hose with the bow of the boat down a sloped driveway? This is an unnatural position for the boat and will revert water then but not out on the water.
I have zero to add about the dry pipes.
I have zero to add about the dry pipes.
04-01-2019 | 06:09 PM
#5
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From: Cape coral, FL
Dry tails aren’t actually dry. The are still water jacketed However by different means the water doesn’t mix with the exhaust stream. Some have bungs with thru hulls. Some are dry to the tip meaning the water doesn’t mix until the end of tip after transom. The above post is correct make sure you’re not bow down or motor tilted forward. Also I’ve been told if you’re only running the risers without the coupler and tip reversion is possible. Plenty of variables
and please turn caps lock off.
and please turn caps lock off.
04-01-2019 | 06:51 PM
#7
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From: Toledo Oh
Dry exhaust is water jacketed.
if you just dump the hose from the manifold, the rest of the exhaust is not water jacketed, nor cooled by water mixing with the exhaust, it will get insanely hot inside the bilge
04-01-2019 | 08:13 PM
#8
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From: belfair, wa
Lol. Not yelling. Was on my work computer and just used to it being that way.
No the nose of the boat is not down. The motor is actually on a stand in my garage. I started it on that.
I figured it would super hot in the bilge but just wanted to see if it has been or could be done. Im going to have to get some taller riser to keep from reverting. I already talked to stainless marine about it was just checking options.
Think it would be ok to run the total dry for a few minutes on the stand with out causing a problem. Would like to run again on the stand untill i get new risers.
No the nose of the boat is not down. The motor is actually on a stand in my garage. I started it on that.
I figured it would super hot in the bilge but just wanted to see if it has been or could be done. Im going to have to get some taller riser to keep from reverting. I already talked to stainless marine about it was just checking options.
Think it would be ok to run the total dry for a few minutes on the stand with out causing a problem. Would like to run again on the stand untill i get new risers.
04-01-2019 | 08:32 PM
#9
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From: Tygart Lake, WV
Running the risers without water won't heat your engine compartment. It will catch it on fire along with your boat.... I wouldn't run them completely dry on the firing stand. Just run enough water to keep them from overheating. How much water were you running when u found it in the manifolds?
