Exhaust hose problems

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cmariner32

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I recently experienced the unpleasant effects of having an exhaust hose and swivel hose burn up during a recent cruise. The right side exhaust hose and shorty hose from the elbow to the swivel fitting burned up. I am having difficulty getting the 4 inch exhaust hose loosened from the fiberglass waterlift muffler and also the other side exhaust hose loosened from the swivel joint fitting. I would really like to be able to save the exhaust hoses that are not burned through. I also cannot loosen the lower bolts on the elbow to the manifold. Any tips to get these items loosened would be greatly appreciated.
 
The hoses have rust. Getting them loose and saving the lap is gonna be a matter of luck. No liquid can help you out there.
A slender chisel maybe? Do you have enough hose left if you cut the Lap off?

Those Bolts have a Nut don't they? IF they do you can get a close-in Nut cracker.
 
On getting the hoses loose, use a long, thin flat blade screwdriver - tap it into the area between the hose wall and the manifold/riser/muffler flange. Once you have it inserted several inches, squirt liquid dish washing soap (I use Dawn)into the gap along the screwdriver blade, then slowly work the blade sideways without pulling it out. The sideways motions will spread the soap and help loosen things up. You may have to do this in three or four locations around the hose.

Don't have any suggestions for the bolts other than Brute Blaster or similar penetrating fluids. When using these, tap the bolt/nut twenty times or so with a small hammer to help the fluid penetrate, let sit ten minutes or so then do it all over again. If it still won't loosen up, apply propane heat to the area around the bolt to get it to expand, apply penetrating fluid to the bolt again and tap, then let sit overnight.

I know you probably don't want to think about this right now, but what caused the hoses to burn through? You should check the exhaust manifolds for blockages to make sure you are getting enough water pumped through the risers to cool the exhaust gases.
 
I was wondering the same thing... what caused them to burn through? If they are old, maybe want to replace the other ones too. Although that tubing isn't cheap... I replaced mine last year because the outside of the tubes were wearing on the outside and I could see the mesh coming through. Contemplating replacing the mufflers this season too. i think they are originals. While my boat sounds really tough (see loud), I bet the insides are pretty charred up.
 
You need something as flexible as a Table knife of Stainless or similar. Chisels will wreck the Rubber part.

Can you get a Dremel tool down to those Nuts and use the cutting wheel to injure the nuts enough to loosen the grip?
 
pix always help!

On separating the hose from it's flange, get one of those short pry-bars that look like a screw driver with a bent tip. grind the tip into a rounded tip and make sure there's no sharp edges to cut the rubber hose. Then work it in between the hose and flange as mentioned above.

The tire change irons are made for working between rubber and steel and not hurting the tire bead surface. They'll work, too. Get at bicycle or motorcycle shops.
 
Thanks for the ideas guys on how to free the hoses from the fittings! My first thought for what caused the hose burn thru is a clogged elbow. I had noticed that when I first start up the engines, the exhaust water is quite rusty. I plan on changing the elbows-the engines are fresh water cooled so I don't think the manifolds are the problem. The bolts holding the elbows to the manifold are 12 point bolts-not hex bolts. Today I went to Sears and purchased a socket made for 12 point bolts and a flex joint so I can make another attempt at loosening the bottom bolts. Worst case, I use my cutting blade on my mini grinder to cut the heads off the bolts. Since I'm replacing the elbows anyhow, no harm no foul. In looking further, I discovered the original owner had apparently eliminated the 90 degree fiberglass fitting from the elbow swivel to the waterlift muffler-its amazing how much you miss until you really look hard at things. I plan on bringing the exhaust system back to original spec and the long hose should have enough excess so that I can still cut off the hose at the end of the swivel and reuse it. The short piece on the other side of the engine however will need replaced.
 
I always use a heat gun to warm up hoses I'm trying to remove. Seems to make a big differnce especially with wire reinforced exhaust hoses.
 
quote:
Originally posted by Dave H

I always use a heat gun to warm up hoses I'm trying to remove. Seems to make a big differnce especially with wire reinforced exhaust hoses.

Click to expand...


+1
 
For any hose you are going to replace, and that should include all the hoses on the side that has the burned one since without sufficient previous RW flow they are cooked on the inside too, just slice the hose over the casting flange. For ones I want to save, I spend a lot of time prying between casting and hose to free up as much as possible , squirt in some WD-40, raising the unfastened riser/elbow from the manifold and use that elbow to apply substantial twisting leverage to break the remaining bond between elbow and hose and/or hse and muffler. Much of my prying is done with tools similar to Charlie's , except where clearance is tight I have one that I heated to white-red with a propane torch and bent a little less than 180* so I can pry towards me and tap the tool at the bend. A nice thin putty knife ground narrower can be tapped in in nicely too.

Keep in mind, anytime exhaust was llowed to get hot enough to burn through the hose there is a good chance the f/g mufffler may have been damaged as well ( loose baffles or drain plug?)

For the elbow fasteners , a lot of times it's the smooth bolt or stud shaft inside the elbow that is badly rusted to the casting , so multiple applications of PBBlaster or Kroil and patience can help, plus CRC Freeze-Off and or torch heat and/or hammer or impact wrench vibration . Never-seize applied in those areas to the new fastners can make the next removal easier. I think I've had decent luck with a curved 12 pt closed end wrench , similar to a brake wrench. I believe at least part of the reason for the 12 pt fasteners there is it allow a 12 pt open end wrench to rotate slightly before fetching up on engine or elbow casting but still finding strong purchase on the fastener when repositioned just 1 point or 30 degrees.

FWIW, as long as lack of RW flow is not due to an hull intake or strainer blockage and/or rapid impeller failure , the burned-hose situation can usually be pretty easily avoided by regularly feeling the top-aft of the elbow with your palm and not delaying riser/elbow water passage inspection if you cannot keep your hand there indefinitely.
 
Sandy...Great idea about the Freeze-off. I purchased a can of that a few months ago to free up another corroded bolt but never used it. The bolt is a 3/8 12point. The distributor wrench I have is 1/2 & 9/16. I bought a 3/8 ratchet box wrench at Sears several years ago when I had trouble with my other boat which had the small block Crusaders but the same type of elbows with the indents. I broke the wrench when I applied a "persuader" to the wrench and began to crank down. Sears happily replaced it, but the wrench is only 6 inches long and you cannot get much leverage with it. I'm hoping the muffler is ok as only one exhaust bank was damaged. Hopefully, the water coming in from the other bank kept the muffler from being damaged.
 
The most likely cause of the burnt hose is clogged water passages in the risers. They
have to make the raw water passages small to restrict water flow out of the risers...
believe it or not. The reason is so he riser will stay full of water before it drains
out. The reason there is so the top of the risers won't get overly hot from he air space.
 
A couple more suggestions: It is highly recommended to NOT reuse those fasteners (particularly bolts, studs and lock washers) as they will have stretched/deformed a bit under torque tighting and heat/cool cycles. And recheck torque value after a couple/few runs & cool-downs. I think Crusader recommends ~~ 25-27 ft-lbs for manifolds and riser/elbows, but best check that.
 
I have always used new bolts when I remove the elbows-it's cheap insurance, the lock washers....not so much. Would they be affected enough to make a difference? I am planning on going down Sunday to see if I can get the bottom bolts off with the tips gathered over the week. Wish me luck!
 
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