turborich

My Feedback: (3)

Hey guys, This is in my shockwave 36. The motor has a water cooled head so the actual motor stays fairly cool but the exhaust is a different story. It is hott!!! It gets so hot that it will easily burn your hands, keeps melting the couple so now i'm using a high temp coupler that I spent $10 bucks on, gets so hot it melts the locktite off of the header bolts & they come lose. The guys at the hobby shop said that it perfectly normal for nitro boat pipes to get this hot but it doesn't seem right to me. Right after I ran it checked the temps, 180 at the head & 315 on the exhaust header/pipe. I keep making it richer & richer but then it won't run very well. I was going to tap the pipe & run water to it butI have been told this is a no-no for nitro boats since the pipe needs to be hot to make power.So, can somebody point me in the right direction?

Thanks, Rich

1150ap

get some soft brass tubing from the LHS and wrap it around the header from where it bolts to the engine it will come almost back to the preasure fitting.

amax

That temp is just fine on the pipe, All Exhaust Systems get hot, your passing fire through it,,It's gonna get Hot. When you richen the fuel mixture it will get even hotter, the extra fuel that is not burning in the engine is burning in the pipe.
To fix header bolts from backing out get Longer bolts and put nuts on the back side to lock them in.
You can take 1\8 alluminum tubbing and wrap it around the header or coupler a few times to make an exhaust cooler, run the water from the head to the exhaust cooler then out the boat. That will help your couplers last longer.

jaredk19

just get some 1/8 inch brass like stated before and block off one end and fill with sand and then wrap it around your header and then pour the sand out the sand keeps the tubing from breaking or kinking

Ron Olson

My Feedback: (1)

Tapping into the header to cool it isn't a good idea as when you shut it down the water can flow down into the combustion chamber. If it's in a Pro Boat boat which I'm kind of assuming that it is, with the hatch on it doesn't let enough air in and out of the hull so things are going to get warmer in there. There's also been issues with the Pro Boat silicone couplers melting and/or cracking.
If you decide to make a header cooler and don't have sand handy, regular table salt works well. Anneal the brass tubing by heating it up (I just do it on the stove) then dip it in water.

idocdave09

My Feedback: (1)

Aluminum tubing will transfer the heat faster than brass. Plus it will bend real easy with the sand in it.
Take your time to make sure all of the sand is removed from the tube when done.

Dave

turborich

My Feedback: (3)

Ok, Guys, thanks for the great tips! I really appreciate it.

I went to the local mom & pop hardware store & picked up some 1/4" copper tubing, 1/4" micro fuel line, 3mm nuts& then went over to autozone for some gasket material.I 'm tired of spending $5 bucks or more on each nut, bolt & gasket! so a huge roll of gasket material was only $5 bucks & will last for years.

So here are the pics, I've got about 6 turns around the header pipe & it seems to be doing the trick. I fired it up on the stand with water flowing to the water pick up. I ran it for a good while & the hottest the engine got was around 125 degrees, the head was closer to 100 & the header seemed to be right around 135 with the pipe at 150.

I'm sure it will warm up when under a load but not like before. Wow this really works!

THANKS A BUNCH GUYS!!!

BTW, the salt is a PITA to get out of the tubing! I had to keep taping it & used compressed air to get it all out. It did the trick though!

amax

the 1\4 inch line is a bit overkill but if ya got it all to fit then run it, 1\8 or 5\32 is more the standard size.
A couple more things that might help ya is,,
Always Loosen the glow plug about 1\2 to 3\4 turn when starting to release some compression, that will help prevent the Tiger Drive from stripping and make it last longer.
Keep the Flex Shaft Greased Always, it's a good idea to always remove the flex shaft at the end of a day on the pond and either store it in oil or at the very least clean it and grease it good.
This one is Your Choice, Toss the Teflon Liner on the flex shaft unless your gonna grease it every time you finish a run, when the grease is slung out and the liner is semi dry, it will create drag and the friction will melt it around the flex shaft, and you will run faster without it.
Header Gasket,,, I Personally Don't Use One,, I take a Good Mill File and make sure the mounting flange is good and flat where it mates with the engine, and put a thin bead of Silicone on it when I install it. Let the silicone Dry Completely before you run it.
If your using the Stock Prop,,Don't,, You will regret it soon. The stock prop is Not Balanced or Sharpened. A unbalanced prop will Literally Rattle the strut Off and I don't mean Loosen it I mean Break it off. Been There. An unsharpened prop Slaps the water when it should be Slicing it. A good Sharpened, Balanced, and polished Prop, will make the boat handle much better, run faster, and your drive train last longer.


and Oh Yea,,
Have Fun!!

TCHedOff

Have you run your boat since you set up the cooling?

I'm curious how it runs vs before you made the change.... Grimracer & I were spoke briefly this last weekend about pipe temps.... his take is that hot is good (and I suspected as much, based on somethings I saw in my own boat last summer).... one of his exact statements was "You can NEVER run a pipe too hot".

Personally, I'd of just suggested better couplers.

advanced builder

Fuel & Air keep the engine itself cool, except were the combustion is. Exhaust I don't worry about.

amax

I put a 1\8" alluminum cooler directly on the exhaust coupler, basicly to make it last longer, and I use the exhaust cooler to heat my engines in the cooler months, especially the Go Engines they run much cooler than most.

turborich

My Feedback: (3)

Yes, I ran the boat today & she performed GREAT!!!  It ran very well & had full power, I brought it in after a few hard runs & checked the temp. 120's on the motor & not much more on the header, the hottest part was the expansion pipe & it was around 150. I was also able to lean the motor out by about 1/4 of a turn.

I was about to get rid of the darn thing because I was tired of messing with it due to the high temps, sometimes it would get on plane & rip & other times it would seem at maybe 3/4 power. Now it's full power when you want it. I am very happy.

Thanks guys!!!

rgoers

Holy COW! Do you ever run that thing? It's so clean you could eat off it! :-)