Cowling Insulation

[mercurymang]

All the insulation was removed from the cowling on my 74 merc. What is the recommended production to replace it with?

 

[Star]

Re: Cowling Insulation

I used indoor outdoor carpet glued in my 05 4 stroke (no insulation installed by factory) what a difference! It may not be as flame retardent as Dynomat but it didn't cost the $75 that dynomat would have.

 

[Texasmark]

Re: Cowling Insulation

Probably didn't have any to start with. Merc was slow in following OMC in making engines quiet. I had them from '59 Mark 30 thru the years to the current '02 90 hp and the only one with it is the current one with a plastic hood.

If you want to glue some in, you could do as Star mentioned or use some 1" open cell foam (like cushions are made of) held in place with rubber cement....coat both surfaces, let it dry and stick it together being careful that you get it right the first time (straight) as you only get one chance without redoing the whole thing.

Mark.

 

[mercurymang]

Re: Cowling Insulation

The PO said he removed it because it was crumbling. I must say i felt stupid opening up another thread on this as after doing some searching, i found quite a few threads that already addressed this issue. Seems to me that the most important things are that A) whatever you put in there doesn't catch fire easily and B) wont fall off and either get tangled in the flywheel or ingested by the carbs.

 

[carholme]

Re: Cowling Insulation

If you are going to use any insulation, make sure it has an external covering for the very reasons you have already found.

Gerry

 

[ajgraz]

Re: Cowling Insulation

I have considered putting some sort of sound insulation inside the cowling on my old Merc, but the possibility of some of it flaking off and getting ingested in the carbs just didn't seem worth the risk compared with the minimal sound reduction I'd expect to achieve.

 

[merc850]

Re: Cowling Insulation

I used fiberglas household insulation cut to size then covered it with shrink wrap. I sealed it by melting the edges together, but not the flat sides, so far no problems.

 

[Dave1027]

Re: Cowling Insulation

Years ago I removed the fuel saturated foam and installed a quieting metal faced padding material sold for that purpose but it's still too loud. I might try "Dynamat" next.

 

[Texasmark]

Re: Cowling Insulation

I used what I said and had no problems with it in roughly 10 years of use after installation.