Replacing Manifold and Riser (use Anti Seize or not)

[mr300z87]

After doing some dis assembly work on my 93 3.0L Alpha 1 gen 2 I discovered my high speed over heating issue is most likely being cause by a clogged water passages in the manifold 2 out 3 completely clogged (and corroded flange ) and a clogged corroded riser. Both had merc part# on them would bet they are 17 year old originals. I have ordered a new manifold and and riser and if they arrive this week will be installing this weekend. My question is do I use Never/Anti Seize compound on the bolts or something else? In all my previous auto work I have used in on just about everything to insure the fasteners come off again. I thought I read somewhere that never seize compound is not good for marine used but could not find it again. All have a great day.

 

[zbnutcase]

Re: Replacing Manifold and Riser (use Anti Seize or not)

I prefer Permatex Aviation sealer, most auto parts carry it.

 

[atomb]

Re: Replacing Manifold and Riser (use Anti Seize or not)

+1 on the aviation permatex thats what i used.

 

[Haut Medoc]

Re: Replacing Manifold and Riser (use Anti Seize or not)

+1 on the aviation permatex thats what i used.

I agree.........

 

[rodbolt]

Re: Replacing Manifold and Riser (use Anti Seize or not)

if your gaskets are the shiny slick mercury ones DO NOT use sealer on the gaskets.

 

[gozierdt]

Re: Replacing Manifold and Riser (use Anti Seize or not)

I'd use anti-seize on the bolt threads, to help them come out next time you need to work on the manifolds and risers. Make sure to torque them properly.

 

[mr300z87]

Re: Replacing Manifold and Riser (use Anti Seize or not)

So I use put the Permatex Aviation sealer on the bolt threads and torque as specified. I don't normally a put any sealer on gaskets when working on my cars other than maybe a dab to help hold it while bolting together. Assumed the same here unless it see its called out in the Manual. I hate cleaning the stuff off next time. Thanks for the advice.

 

[littlebookworm]

Re: Replacing Manifold and Riser (use Anti Seize or not)

Check the Mercruiser manual for your engine as to whether you use any sealer on the gaskets; some do, some don't. You asked about using no-seize on the bolts (not the gaskets). I personally never have, I'm less concerned with the bolts getting stuck than with them loosening. A little trick to do the manifolds: Get two extra bolts longer than the ones holding your manifolds. Cut off the heads. You now have two long studs which can act as a second pair of hands when removing or installing the heavy manifolds. Remove one outer manifold bolt. Replace it with a stud. Remove the other end manifold bolt. replace it with a stud. Then remove the center bolts. Slide the manifold off the studs. On install, reverse the process. It saves scraped knuckles and broken spark plugs. Before you put the manifolds and risors on check their mating surfaces for flatness. You can use a flat file drawn lightly across the surfaces to clean off any casting slag. This eliminates leakage. Good luck. Hy

 

[Brentathon]

Re: Replacing Manifold and Riser (use Anti Seize or not)

There are very very few applications, where a tiny dab of anti-seize or even standard grease on bolt threads would actually be detrimental.
In the aerospace industry, I see anti-seize called-out on drawings quite often.
It's not just a corrosion preventative, but also helps prevent galling on assembly.
I've been using anti-seize or grease on bolts, more and more over the years.......I believe the possibility of causing bolts to loosen is close to nil, if the bolt is torqued even close to the proper torque.

 

[mr300z87]

Re: Replacing Manifold and Riser (use Anti Seize or not)

I have been using for years also especially since I tend to keep my cars for a long time and here in the rust belt of NJ bolt get corroded fast and these little 6mm 8mm the auto industry like to use break really easy when the need to be remove. So a little anti seize helps a lot. Was not sure if the salty moisture in a marine environment would react with it. It is nasty though.

 

[jerryjerry05]

Re: Replacing Manifold and Riser (use Anti Seize or not)

I worked at a marine service center for a number of years and they never used anti-sieze.We were around salt water.Something about saltwater making it perma-sieze.
Manifolds and risers if the mating surfaces are clean/smooth don't really need sealant(I use it).Some gaskets have a sealer on them.Manifold bolts don't need anti sieze.
Head bolts. Yes,use it.J

 

[sasto]

Re: Replacing Manifold and Riser (use Anti Seize or not)

I worked at a marine service center for a number of years and they never used anti-sieze.We were around salt water.Something about saltwater making it perma-sieze.

We did an expierement with Anti- Seize in saltwater. You are right....perma-seize. We use Teff-Gel, comes in a small syringe...and use a small amount.. I havn't seen many posts about the stuff.....but we have been swearing by it for years. Many uses. We can pop off a 36inch, 100 lb. prop. easily using Teff-Gel on the shaft spline and in prop hub.

Man Engines recommended Anti-Seize on the injector installation....which I do every year. That was a mistake....we use only Teff-Gel now with great results. Almost all engine bolts, plugs, and even fuel lines get the stuff.

Anybody else ever use Teff-Gell?

 

[Fishermark]

Re: Replacing Manifold and Riser (use Anti Seize or not)

Never heard of Tef-Gel till now. Did a quick search.... pretty expensive stuff. I guess I would ask why use it when either grease or Permatex Aviation Sealant (or even Permatex #2 for various things) works well. And a whole lot cheaper.

 

[sasto]

Re: Replacing Manifold and Riser (use Anti Seize or not)

Never heard of Tef-Gel till now. Did a quick search.... pretty expensive stuff. I guess I would ask why use it when either grease or Permatex Aviation Sealant (or even Permatex #2 for various things) works well. And a whole lot cheaper.

Tef-gel appears to me to last and last. Use only a small amount, has teflon. Other than that...I really don't know. Most all the boatbuilders, mechanics, and captains around here use the stuff. I know little about these Permatex products so I can't compare. I am refering to the bolts, not gaskets. I guess we stick with what works best for us. As far as cost...little goes a long way..when you factor in overall cost of running a boat...I prefer to pay more for products that I believe in.

 

[Fishermark]

Re: Replacing Manifold and Riser (use Anti Seize or not)

I'm talking about bolts as well - not gaskets.

Hey I agree that the cost is negligible in the long run. I also agree that it is a good idea to stick with what you believe in. I just happen to believe in grease and Permatex.

 

[pwpns]

Re: Replacing Manifold and Riser (use Anti Seize or not)

Loctite make a marine grade anti-seize that is metal free. here is a link to their web page http://www.henkelna.com/cps/rde/xch...tredDotUID=productfinder&redDotUID=0000000I3Z

 

[Brentathon]

Re: Replacing Manifold and Riser (use Anti Seize or not)

Permatex Anti-Seize make this claim:

A highly refined blend of aluminum, copper and graphite lubricants. Use during assembly to prevent galling, corrosion and seizing and to assure easier disassembly. Temperature range: -60?F to 1600?F (-51?Cto 871?C). Salt, corrosion and moisture resistant ? ideal for marine use. Non-aerosol version meets Mil Spec #907E. Aerosol - Level 3*

Seems like the stuff should be OK....

 

[Lyle29464]

Re: Replacing Manifold and Riser (use Anti Seize or not)

Most of the exhaust manifold bolts I have had a real hard time with were frozen at the shoulder of the boat not the threads. If the threads go into the water jacket gasket sealer is better than greese. Stainless works for a while but will turn to mush in a couple of years. High temp paint seems to work better than greese or gasket sealer.

 

[Eric 3.7LX Alpha 1]

Re: Replacing Manifold and Riser (use Anti Seize or not)

From what I've read on neversieze, the problem is with the dis-similar metals being joined: stainless bolts into aluminum.

I've used it for years on car repairs, but since reading on here about it being perma-sieze in salt water applications in boats, I have been using grease instead on the boat fasteners.

 

[mr300z87]

Re: Replacing Manifold and Riser (use Anti Seize or not)

Well everyone seem have their 2 cents on this one. I was thinking of using the Permatex Aviation sealer on any of the threads that are wet (IE the end plates) and possibly hi temp grease on the bolt shafts where it goes through the manifold. Although the boat is 17 years + old and all 5 manifold bolts came loose. I just purchased it a month ago so I do not know the age of the manifold or riser. Both had Merc part #s on them so could be original although I am told the don't normally last 17 years The motor has 300 hrs on it. Thanks for all the input.