Exhaust elbow gasket

[Roc]

Hello All and Happy New Year,
I removed my exhaust elbow so I can easily remove the hose leading to the muffler in order to replace it with a more flexible Vetus exhaust hose.  Question I have is I noticed a carbon-like gasket between the elbow and engine.  Is this something that I can re-use??  Or, should I get a replacement gasket.  Also, should there be any sealant applied?  I don't notice any sealant, but the gasket is stuck to the elbow when I removed it.  Probably just stuck from clamp pressure.  But just wondering if any sealant is/or should be there.

Thanks!!!!
Roc
Sea Life #1477

[Ray & Sandy Erps]

I did this same repair about three months ago and re-used the gasket after applying some high temp RTV silicone.  No problems so far.

[Ed Shankle]

I would replace the gasket; I aways consider that "SOP" when taking a gasket joint apart.
Last time I replaced it I didn't use any gasket sealant, however, I think from previous discussions about the joint, Ron recommended using a sealant.

Ed

[Roc]

Thanks for the info....where do you get the gasket??  Like I said, it looks to be made of a brittle carbon material.  Also, what's RTV silicone?

Thanks!!

[Ray & Sandy Erps]

RTV stands for "room temperature vulcanizing" I think.  NAPA sells lots of little tubes of silicone for different applications.  One is labeled "Hi Temp" and I think it says it's good for exhaust manifolds.  For all I know, it all comes out of the same big pot and they add different colors to it to trick consumers.

Anyway, I agree with Ed that it's best practice to replace the gasket.  I didn't have any suitable gasket material on hand so I re-used the old one.  I did this knowing that the pressures are relatively low, the surfaces were in good shape and the old gasket was in good shape and it was easily observable to see if it failed at some point.  Your local NAPA store sells gasket paper and if you describe where the gasket is going, they will be able to point you to the right product.  The stuff you need is thick stiff stuff and it's kind of hard to cut, but it resists the high temperatures.

[Stu Jackson]

Roc,

Is it the green gasket between the manifold and the exhaust riser?

If so, replace it.  Why mess with a "single point of failure?"

It's a $1.83 item in a $7,586 system.

[Ron Hill]

Roc : Are you saying that you separated the exhaust riser flange from the engine exhaust manifold on your M35B engine?  
You best look in you M35 parts manual and at least get a spare gasket to have on hand - in case you have an exhaust or coolant leak.  

[Roc]

This is the gasket that goes between the exhaust outlet on the engine and the foil covered elbow.  Talked to Westerbeke about this.  The gasket part number is 036425.  They suggest using Permatex 'Hi TAK' sealant to both sides of the gasket.  The Hi TAK product is red in color.

Take care,

Roc

[Mike Vaccaro]

Roc,

The sealant is the key to avoiding coolant in the exhaust.  Even a very small amount of glycol that is is heated up in the exhaust produces a noticable ("sweet") odor.  At best this is annoying, at worst, you'll lose coolant to the exhaust over time.  Unfortunately, the gasket doesn't seem to do the trick by itself.  Don't know if this is the fault of the flange or gasket design.  Recommend that you always change the gasket any time you open the flanges and use an appropriate high temperature rated sealant.  The sealant won't complicate future dissassembly, but will require a bit of cleaning (scraping) each time the joint is disassembled.  

Cheers,

Mike