Cleaning gasket material off dry-joint exhaust????

[sfakeith]

Hi everyone, I am new to this forum and am hoping someone can help me. I have used the search function but can't find the answer I'm looking for. I am installing new manifolds on my 2005 merc 5.0 with dry-joint exhaust. I have purchased all new gaskets but my concern is cleaning all the old "silver paste" off the risers, elbows, and heads. Does it all need to come off? Does it need to be absolutely free of old gasket material? Can I use a steel brush attachment on my drill? What do the professionals use to get this stuff off?

 

[MWG2600]

Re: Cleaning gasket material off dry-joint exhaust????

A razor blade, Are you talking about the surface on the head? anaway it has to be clean.

 

[Don S]

Re: Cleaning gasket material off dry-joint exhaust????

There is no real gasket to scrape off on the dry joint system. Nothing should be there but some old sealer.

You have to be careful with using power brushes of any kind. To much and you can round over surfaces and destroy them. Pro's know this and tread lightly where needed.
Use a razor blade as mentioned, or a putty knife to scrape the sealer off. Then follow the sealing instructions in the manual for the new gaskets.

 

[sfakeith]

Re: Cleaning gasket material off dry-joint exhaust????

Thanks for the help! i tried just using a razor blade but all the "silver paste" does not come off. Using a putty knife is doing the trick either. I just dont know how clean the surface needs to be. Do I need to have clean cast iron for the new gaskets to seal properly?

 

[Don S]

Re: Cleaning gasket material off dry-joint exhaust????

Post a picture of what you are seeing.

 

[Fun Times]

Re: Cleaning gasket material off dry-joint exhaust????

What do the professionals use to get this stuff off?

I like to use this,
3M7526 3M 50 Grit 3" Roloc Bristle Disc for Die Grinders | eBay

 

[sfakeith]

Re: Cleaning gasket material off dry-joint exhaust????

I like to use this,
3M7526 3M 50 Grit 3" Roloc Bristle Disc for Die Grinders | eBay

Will try this for sure! Thanks again!

 

[Fun Times]

Re: Cleaning gasket material off dry-joint exhaust????

Will try this for sure! Thanks again!

If you do end up using this tool then like Don mentioned in post #3, Just tread lightly using this tool being careful not to go to deep in one area vs the other. The nice thing about this tool is that it's pretty hard to remove any surface material from the manifold, etc, but you still need to be careful.

On page 7B-5 of service manual #37, the manual tells you how much surface material can be removed only if needed, and more importantly it shows you the surface area that should be checked for flatness.

You've just got to be confident in yourself with this one. Good luck.

 

[achris]

Re: Cleaning gasket material off dry-joint exhaust????

I have a few tools for cleaning gasket surfaces. I select the one most appropriate to the surface being cleaned.
I have a razor blade scraper, a 1" wood chisel with a VERY sharp edge, and a brickies float with a length of 120 grit emery cloth on it. The brickies float is really good for long surfaces such as aluminium outboard cylinder heads and manifold gasket surfaces.....

 

[Howard Sterndrive]

Re: Cleaning gasket material off dry-joint exhaust????

My dry joint Merc manifolds had this Silver paste as well. I used a razor blade and then cleaned it off with fine sandpaper.
I asked here once about a part number or what to use at reassembly
http://forums.iboats.com/mercruiser...ifolds-sivery-paste-riser-gaskets-582056.html
and it's as if the OP and I are the only ones who have seen it. Maybe it was a short lived thing at Merc. or they only use it on surfaces they aren't completely happy with maybe.
I used muffler cement at reassembly. It looks and feels exactly the same. I'm not sure the function of this paste,

but I just applied a film of it with my finger when putting the risers back. Get ready for a $80 pair of riser gaskets too.
It's all good now - I ran last season with no issues after using the $4 muffler cement with the new gasket plates.

 

[sfakeith]

Re: Cleaning gasket material off dry-joint exhaust????

With everyone's help, i finally got the new manifolds installed along with the risers and the elbows. Started the engine and ran it for for 20 minutes with no leaks to be found.

But, I am unhappy to report that the motor is running hotter than normal. I will say that I have never had it run that long on my hose attachment and am hoping that there is just not enough water getting into the motor. We'll see. I am going to to post a new topic to see if anyone can help me with this. Thanks again all!!!