3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

[TommyRox]

I have n issue on MY 99 BowRider Mercruiser 3.0. I had to replace my exhaust flapper last week and now that it's all put back together - leaks water. I have taken it apart and clean it to bare shiny metal - almost looks new and replaced the gasket. SeaRay says to install gasket dry so that was the last thing I tried - still leaks. Before I used an RTV gasket sealer and cleaned and removed 2 times - both times leaking. I cannot imagine anything is warped...is there a secret to getting this leak to stop? I don't think the riser or manifold in my case needs to be replaced as they look brand new. Will post pics if needed...

Thanks in advance. GREATLY appreciate any feedback

TommyRox

 

[Fishermark]

Re: 3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

How did you clean it? A flat metal file works best as it doesn't "curve" the surface the way sanding might.

Also - what gasket are you using? If it is the green paper type, throw it away. Use the grey graphite one from Quicksilver. And yes, put it on dry.

 

[TommyRox]

Re: 3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

I did all the above - I used a razor blade at first then a file and finished with steel wool. I went to MarineMax and got the QuickSilver grey gasket ( 2 times). It never leaked before I took the riser off but it did over heat one time. I mean it looks level on both sides but do you think it could be warped? I was thinking that maybe the screws could be tighter - just don't want to break one off in the manifold. Any suggestions would be greatly appreciated.

 

[fishrdan]

Re: 3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

Have you checked to see if the gasket surface on the manifold and riser are flat and true, checked it with a flat edge and feeler gauge to see if it's warped? I'm guessing you can see where it's leaking from, anything odd looking in that area? How tight are the nuts? I usually just tighten them down with my calibrated elbow, but there is a torque value for those fasteners, not sure what is off hand though.

Also, if it's leaking out, it could be leaking IN Need to get the gasket problem fixed ASAP of you could get water into the cylinders.

 

[TommyRox]

Re: 3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

I have included pics of what I am working with. I noticed that the gasket from Quicksilver seems to have smaller holes on the outside then the riser and manifold. You can tell on the pictures of the gasket by the rust mark that it doesn't line up. Wonder if I need to cut the gasket out to match the hole size. I used as file and steel brush to clean both surfaces and each side appears true and level.

Riser -
http://share.shutterfly.com/action/welcome?sid=0ActmzRkzZNWjrI
http://share.shutterfly.com/action/welcome?sid=0ActmzRkzZNWjtQ

Gasket -
http://share.shutterfly.com/action/welcome?sid=0ActmzRkzZNWjvY
http://share.shutterfly.com/action/welcome?sid=0ActmzRkzZNWjyo

Manifold -
http://share.shutterfly.com/action/welcome?sid=0ActmzRkzZNWj0w
http://share.shutterfly.com/action/welcome?sid=0ActmzRkzZNWj24

 

[fishrdan]

Re: 3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

2nd riser pic looks like there are deep scratches in the machined surface (looks...)

Gasket pics show the gasket isn't being squeezed evenly, not crushed even all the way around

Manifold still has old gasket material on the surface in certain area's, probably why the gasket didn't crush evenly

 

[Bt Doctur]

Re: 3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

It does look like some gasket material is left on.Try using a fine flat file on both surfaces and you might try Perma-Tex aviation sealant

 

[Bondo]

Re: 3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

Wonder if I need to cut the gasket out to match the hole size.

No....

'n I agree,... Lotsa gasket material left on the manifold...

 

[TommyRox]

Re: 3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

Awesome replies!!!

Manifold - indeed you guys are right on it seems - didn't think the small amount would matter - I keep filing on the manifold with a fine file or drill with a wire brush.

Gasket - do you see where the indentions are - that the gasket holes are smaller then the inlet holes and hence would be getting hit directly with the flow of water. I was going to put the gasket on my drill press and try to open them up to match the holes. what do you think?

http://share.shutterfly.com/action/welcome?sid=0ActmzRkzZNWj4A


Riser - Those scratches indeed look deep but it's actually the light and camera angle that make them appear that way. When you look at it there are superficial and very smooth to the touch.

Note: I did try RTV 2 times before but you think Perma-Tex aviation sealant would be the best? I was told by SearRay and MarineMax to install it dry but I figures some sort of sealant couldn't hurt - your thought?

Thanks again guys for all the replies and comments!!!!

Thomas

 

[Bondo]

Re: 3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

Gasket - do you see where the indentions are - that the gasket holes are smaller then the inlet holes and hence would be getting hit directly with the flow of water. I was going to put the gasket on my drill press and try to open them up to match the holes. what do you think?

http://share.shutterfly.com/action/w...ActmzRkzZNWj4A

Ayuh,... Like I said before,...
There's Nothing wrong with the gaskets,...
DON'T cut 'em...

 

[Bt Doctur]

Re: 3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

I use the aviation sealant on everything ,especially gaskets where liquid is present.
head bolts , intake gaskets around the water passages,hardware that need corrosion protection, bolt that will need to be removed at some point, fuel systems.
Has never let me down .
Silly-cone is never used except on the front and rear of the block to seal the intake manifold, and the 4 corners of
the oil pan and you use the Black RTV there.

 

[fishrdan]

Re: 3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

I use aviation sealant on the riser gasket too, even though they say to put it on dry.

 

[airshot]

Re: 3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

I used a pocket knife to scrape away the old gasket, took the edge off the knife but did not gouge the parts. Check the surfaces with a straight edge, they may appear straight but a straight edge is the only sure way to tell. Clean out the thread holes very well and be sure threads are good, if necessary run a tap into them to be sure they are good. That cast iron flakes and gets into threaded holes and may not allow the bolts to be threaded far enough.
In other words when you think they are tight, you may be bottomed out in the hole due to crud.
I was able to clean out and gain more than 1/4" of extra thread which can allow you to be sure you are tightening down on the gasket and not bottoming the thread. I did all this and had no problem.
Airshot

 

[TommyRox]

Re: 3.0 Mercruiser Riser to Manifold Leak - 1999 SeaRay BR180

UPDATE: there was a little gasket matierial on the back left corner - little elbow grease and issue resolved - no mo leak. I want to thnk everyone for the suggestions and feedback - saved me a few hundred dollars.