Mercruiser 470 with 1.84 MC-I sterndrive - exhaust bellows still good?

Blueghost924

Petty Officer 1st Class
Joined
Sep 19, 2013
Messages
250
Need an opinion on something. When I bought my boat last year, it didn't have the exhaust bellows or the shift cable bellows. But, inside the cabin the previous owner left an exhaust bellows that looks like it's never been used. Again, this is from November 2013. This exhaust bellows has never been installed (that I can tell), seems very flexible and doesn't looks like it has any cracks or such in it. I even filled it up with water after putting it vertical on a glass plate - didn't see any leaks. Opinions - still a good bellows? It hasn't been exposed to the elements.

Offhand, the u-joint bellows is still attached to the gimbel ring. I'm not sure if it would be a good idea to remove it and see if it's still good. Or play it safe and buy a new one. The shift cable bellows will definitely be replaced with new.
 

stonyloam

Vice Admiral
Joined
Mar 13, 2009
Messages
5,827
Use it! The exhaust bellows is open to the water on the aft end and is normally filled with water when the engine is not running. Its only purpose is to direct the exhaust from the bellhousing into the outdrive. It would still be usible even if it were full of holes. For the driveshaft bellows, be safe, and spend a few extra bucks for OEM.
 
Last edited:

Blueghost924

Petty Officer 1st Class
Joined
Sep 19, 2013
Messages
250
Thanks for the reply Terry, and will do. Now about that u-joint bellows....wonder if I should take it off and look at it's condition for possible re-use....
 

thumpar

Admiral
Joined
Jun 21, 2007
Messages
6,138
The bellows are glued in and then clamped. If you plan on removing just get new ones to replace.
 
Last edited:

stonyloam

Vice Admiral
Joined
Mar 13, 2009
Messages
5,827
While the exhaust bellows are non critical the drivshaft bellows are VERY critical! A hole there can sink your boat in a few hours, and chances are that taking them off would destroy them in any case, so just go ahead and replace them and don't worry about it for the next several years. The OEM Mercruiser bellows are well worth the extra cost IMHO. While you are at it take a look at your trim limit switch and trim sender. Now is the time to change them if needed., your lower shift cable too. Might as well do it all at once. Take a look at your water hose from the bellhousing to the transom. If it is in good shape you may not have to change it, but if it is showing cracks, it would be best to install a new one. Oh yeah, you have a 470, so change the impeller and since it is a new to you boat it would be best to install a new impeller housing as well. You never want to overheat a 470 and the best insurance is to replace the impeller every second year. Good luck and welcome to the 470 club
eek.gif
wink.gif
 
Last edited:

Blueghost924

Petty Officer 1st Class
Joined
Sep 19, 2013
Messages
250
Thanks Terry - and a new u-joint bellows and new shift cable bellows WILL be installed (including the use of the adhesive). Looks like Sierra part number 18-2751 is the ticket for my 1.84 MC-I.
 

Fishermark

Vice Admiral
Joined
Oct 19, 2003
Messages
5,617
The Sierra part will fit and will probably work just fine. But to emphasize stonyloam's point, he recommends the OEM Quicksilver brand instead of the Sierra or other aftermarkets. The OEM part number is 60932A4. Whichever you choose, I certainly agree with all the above that you certainly need to replace it and not worry about the exhaust side. The one you have available is just fine for that.
 
Top