merc 4.3 riser gaskets

M

MATMAN29

Seaman Apprentice

Joined

Apr 1, 2005

Messages

36

• Apr 2, 2005

• #1

I have a 99 4.3 mercruiser.I replaced the exhaust manifolds,risers & elbows last season.I took the elbows back off this year to replace the flappers and noticed the riser gaskets had leaked internaly I torqued them to the proper specs in a criss cross patern when I put them on but they still leaked.The manual says not to use gasket sealer on these gaskets(they are the shiny silver ones)but I dont want them to leak again any one know if its ok to use sealer on these gaskets?they are three inch risers.

 

tommays

Admiral

Joined

Jul 4, 2004

Messages

6,768

• Apr 2, 2005

• #2

Re: merc 4.3 riser gaskets

http://www.boatfix.com/merc/Bullet/99/99_10.pdf <br /><br />thank Don's for this i am just reposting it<br /><br /><br />tommays

 

D

DHPMARINE

Captain

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Dec 16, 2003

Messages

3,688

• Apr 2, 2005

• #3

Re: merc 4.3 riser gaskets

If the gaskets leaked internaly,didn't you get water in the engine/crankcase ?<br /><br />DHP

 

M

MATMAN29

Seaman Apprentice

Joined

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Messages

36

• Apr 2, 2005

• #4

Re: merc 4.3 riser gaskets

no water in the oil but there was water in exhaust manifold didnt look like it was leaking bad but it was leaking.they were completely drained before taking them apart.

 

Don S

Honorary Moderator Emeritus

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Aug 31, 2004

Messages

62,321

• Apr 2, 2005

• #5

Re: merc 4.3 riser gaskets

Check the manifolds and risers shown in the picture below, if they are not clean shiny metal about 1/4" wide then they need replaced before they cost you an engine. If they are a black carbon substance where the red lines are, they must be replaced.<br />Manifolds and risers DO NOT last forever.<br /><br />

 

M

MATMAN29

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36

• Apr 2, 2005

• #6

Re: merc 4.3 riser gaskets

they were brand new last season

 

Don S

Honorary Moderator Emeritus

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Aug 31, 2004

Messages

62,321

• Apr 2, 2005

• #7

Re: merc 4.3 riser gaskets

Missed the "New last season" statement on first post, did you use Merc parts or after market parts?

 

M

MATMAN29

Seaman Apprentice

Joined

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Messages

36

• Apr 2, 2005

• #8

Re: merc 4.3 riser gaskets

I read the boatfix link that says not to use sealent but I have heard of boat techs that do use it.Any sugestions?dont want em to leak again.

 

M

MATMAN29

Seaman Apprentice

Joined

Apr 1, 2005

Messages

36

• Apr 2, 2005

• #9

Re: merc 4.3 riser gaskets

Brand new all merc parts.No after market junk.

 

R

rodbolt

Supreme Mariner

Joined

Sep 1, 2003

Messages

20,066

• Apr 2, 2005

• #10

Re: merc 4.3 riser gaskets

then most likly you missed the surface flatness test.<br /> what procedure did you use for cleaning and what procedure did you use to check surface flatness ?

 

M

MATMAN29

Seaman Apprentice

Joined

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Messages

36

• Apr 2, 2005

• #11

Re: merc 4.3 riser gaskets

they were brand new i didnt know I had to check for flatness.whats the proper procedure for cleanind & checking flatness?For when I put them back together

 

B

bigbrownbuku

Master Chief Petty Officer

Joined

Sep 17, 2004

Messages

885

• Apr 2, 2005

• #12

Re: merc 4.3 riser gaskets

just use a metal rule to quickly check. the gaskets you are using are fairly forgiving. i have found they need to be retorqued after the first run due to there very pliable nature.

 

M

MATMAN29

Seaman Apprentice

Joined

Apr 1, 2005

Messages

36

• Apr 2, 2005

• #13

Re: merc 4.3 riser gaskets

Ok ille check the flatness and go with out the gasket sealer. Thanks Whats the proper cleaning procedure to get the old stuff off can fine sandpaper be used?