changing risers..
J3ff
Member Posts: 4,096 ✭✭✭✭✭
On a closed loop cooling system on a mercruiser 383 do you also change the lower gasket on the spacer? Or just leave it all alone scrape off the top gasket put a new one on and replace?
Post edited by J3ff on
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Port side riser/elbow
Stbd side riser/elbow
Port manifold
Stbd manifold
It is possible they were leaking but as you are in salt air and those are cast all it takes is exposed metal(paint scratchy or flaky) and you get corrosion or rust nearly over night
Any thoughts on the first post? Normally of course you'd change the gasket, but being closed cooling it makes me wonder if it's needed?
As far as those gaskets, i installed all new ones with new gaskets. They are one time use.
Clean all mating surfaces on risers/manifolds/spacers with a large flat file to be sure they are true. If you dont have a large flat file a concrete block (cinder block) works in a pinch. Lay block on flat surface and rub mating surface against smooth side of bare concrete block. Dont use one that is all pitted up and weathered. I installed my riser gaskets with a very thin coat of permatex right stuff on the gaskets.
Torque down in sequence with torque wrench. Re check torque after good shake down run.
Bellows glue helps everything slide into the y pipe bellows when installing. It also helps seal up any imperfections on the surfaces.
If your exhaust bellow joints are hardened or were swelling outward they need to be replaced. Fresh flexible new ones are a pleasure to work with while old hard ones will teach you new swear words.
Ordered a small electric hand sander to get em perfectly smooth.. like some guy on youtube..
Thank you for the tips ! Are you saying I should put some bellows glue on the parts that show salt water leaking?
Yes, bellows glue around where the rubber joints go over the riser/y pipe. It will help seal.
To answer my earliest question on if the clamps around the elbow might leak because they are too loose.... Well I put a socket on an extension and was able to loosen it up by hand, no other tools needed... It turned easily without any Force and off they came... Not sure how that slipped by both mechanics and me but ultimately the Captain is responsible, so it's my fault... Now it's time to turn every single thing that should be tight and make sure it's tight I guess.
Closed cooling:
Sea water cooled:
there are SO freakin' many different configurations of risers/manifold gaskets it's not even a sport to find the right ones- it's lunacy. the ones in the image above this post are for dry joints... there are wet joint ones too... then, there are all kinds of configurations from slotted passages to squared ones, to holes... and man, it get's confusing fast. and it's real easy to get the wrong ones.
then, there are updated gaskets... some say ZERO rtv... some say 'lightly use rtv'... and... then i look at the OE marrying surfaces and ask myself what planet those engineers are from suggesting no rtv? if the surface has to be worked to remove material from the casting process they have no room to tell us not to use rtv... so... i do... an even film.
Honestly I don't even mind because work is really busy right now and I've got a boat that I can take out but instead I'm just sitting here staring at it
If I were at the start of this road 4 years ago I'd be looking for in water flush kits.
Put soap on the blue part, correct? Even if they won't be run for a week or two? Bellows glue won't be here for a few days...
Fresh new soft bellows wouldn't have an issue but older harder ones can use the help.
Dawn soap will make it slide on easily but does nil for sealing. Below glue helps it slide on easily plus help seal.
Many ways to skin a cat. I just dont wanna do it twice.
Regards,
Ian
The Third “B”
Secretary, Ravena Coeymans Yacht Club
https://www.rcyachtclub.com/
there is another bonus in using dishwashing soap for hoses inside the engine room- it bubbles when it leaks. it makes a leak obvious. really obvious. and, you won't have to trim the hoses and hope you have enough if one lets loose for whatever reason... all you have to do is put it PAST the first clamp where water won't encounter it unless the clamp fails.
@PickleRick this is like the second or third time you've straight up countered what i've offered without asking me 'why' first.... do you not think i know what i'm doing if i think enough to comment on it?
On the other hand some sealant around the sealing lip before sliding on the hose, then torque the clamp (or install a god awful spring hose clamp) and issues never came back.
Fresh y pipe bellows will work up and down somewhat easily but the harder ones not so much. If it leaks and he cannot get it to stop by re torquing the clamps he is stuck ripping that riser back off to buy more expensive gaskets.
Dawn does leave a sticky goo behind. When sealing something that hard to access i prefer the gorilla snot. Reused hose clamps shouldn't stretch like new ones but if they do the bellows glue is likely to still be holding strong.
I by no means am saying dish soap won't work, it will but i think that there is already a pretty good product on the market that does a good job sealing bellows.