Exhaust risers do it yourself??

Not sure of exact torque spec off top of my head but I would use perfect seal on the orange rubber seal of the gaskets when installing.
 
west marine, BOW maybe or any mercury dealer ( marinemax should have it Marty or Fernando in parts). you can use it on all fittings. when you torque bolts mounting the riser and extention do it in a cris cross pattern I don't use a torque wrench I cris cross tightening them and you will feel them start to get real tight then stop. Thats the point when the rubber seal on the water passages are compressed and its now tight against the center exhaust passage.
 
flflatrate said:
......I don't use a torque wrench I cris cross tightening them....
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It is true that many experienced mechanics forego using a torque wrench with good results. However, it is not recommended practice. Who wants fasteners to loosen down the road because they were under-torqued? Worse, who wants to deal with broken fasteners or damaged parts from over-torque? The margin between the two is thinner than you might think, and we are well-advised to follow the factory instructions for installing fasteners.
 
rondds said:
Panchita, are you replacing mannys too or just risers/elbows? You have any photos of the manifold passages? I'm curious what they look like after 3 (was it 4??) seasons of Floriday usage. Here's what my (likely original) manifold passages looked like when I pulled them a few months back. I'm guessing they're original b/c the left and right side of the flange of each manifold port features different thicknesses, which necessitates bolts that are two different lengths. The new design has each side of the flange the same thickness. Keep in mind this is a 20 year old boat with full factory FWC, used always in fresh-brackish water...

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Wow- not much left of the mating surface on the lower section of that manifold...are those Mercruiser? I'd read somewhere that the OEM manifolds were worse with respect to those skinny little sections than some aftermarket ones. It just seems crazy that they'd design something like that where a few sixteenths of an inch is what separates the closed from the open side...

I have a 6.0 Crusader where the elbows are also part of the FWC system. I don't understand why other manufacturers don't do the same.
 
Those were Mercruiser. The new ones are much beefier - these are very old and I guess over time, those walls get pretty thin.
 
I don't know if you guys know but they are stop making the 8.1 now and they came out with the 8.2. Heres a pic of it with the latest and greatest catalist exhaust. son all motors bieng sold will have this sort of set up. I just delivered one to Suzie Ormond that has that system on it. Her motor was a 350 MPI. Still working on the dry joint picture.
82.jpg
 
I'm at merc school this week and heres a picture of the dry joint exhaust on a motor without an extension. do you see the humps on the elbow? thats where the water flows thru. I'll try to find a gasket and take a pic of it tomorrow

exhaust.jpg
 
Good catch Todd....my bad.
 
Re: Exhaust risers do it yourself?? UPDATE

Almost finished with the job. Did it myself and it was pretty easy.
No problems with rusty bolts, everything came off very easy and in fact the elbows, and manifolds could probably of lasted another season. I showed them to marine max and they were surprised they looked so good and asked if i flushed after every use and in fact I did 95% of the time, probably missed one or two but never let the boat sit long without flushing between uses. overall i got 3.5 years on them and they May have lasted 4 to 5 years , but I was being cautious..

Hardest part was removing the Darn water heater,, it was leaking and basically had corroded at the connection for the hot seawater connection coming from the engine. If you run your boat in salt water and the heater uses hot engine water to exchange heat into your heater I recommend you remove this and cap off the outlets from the engine,, then just rely upon the electric element to heat water.

The salt water just clogs the system up.
I ordered a replacement and it is at the marina, so tomorrow I go and install the heater then finish my job.:smt038

Anyone wanting to save money on the risers and manifolds ,, this is an easy job but you need to take your time and make sure to use,good parts.
 
Congrats and GOOD JOB! Much more money to spend on gasoline now!
 
All is working perfectly .. now I am going to change the raw water impellors....
 
I did it 2 years ago with aluminum GLM kits,about $1250.00 for both sides. Install new mounting bots.
here is a picture
 
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