EFM 520...How Long???

I wonder if anyone tries using a good quality RTV sealant on the rubber gasket for the coil?

On my AA, I had some pretty significant rust under the rubber gasket, but I didn't want to to a cut=out and reweld,
so I sandblasted the pitted surface, and LIGHTLY buttered the steel and the matching gasket surface of the old gasket.
I had and still have no leaks..

I shut down my boiler every summer, and only once gave the nuts on the plate a 'tweak' with a wrench.

I think that the good quality RTV [I use Permatex 'Ultra-Black' ] creates a waterproof seal that is NOT dependant on the 'crush'
of the rubber gasket to keep water from migrating between the steel and gasket.

Ive got to believe that with a new, clean steel surface and a new soft rubber gasket, that a THIN coal of Ultra-Black would assure
a waterproof seal for decades.

Just a thought. I don't think any other type of sealant would do the job, they all get hard, except RTV.

Greg L

I serviced a efm 520 today and noticed the DHWC was dripping a little. Not sure if I should replace the gasket. I need a second opinion. Should I replace it or let them get a few more years out of this one What do you guys think??

Jeez, you have all the fun!

Run.... Run Fast, Run Far...

MATTHEW D. wrote:I serviced a efm 520 today and noticed the DHWC was dripping a little. Not sure if I should replace the gasket. I need a second opinion. Should I replace it or let them get a few more years out of this one What do you guys think??

Nah, that should be good for a few more years.

You guys have it all wrong! Just put the cover back on and bamm problem is gone see! Great work Matt, thats some impressive work. We don't have any stoker repair/service folks around here anymore. I have a friend who went to SUNY Delhi for an HVAC degree, I asked him did they go over stokers at all? Nope never, thats sad really.

Wood'nCoal wrote:Nah, that should be good for a few more years.

But I'm afraid it might start rusting the boiler if I don't replace it .....

as Clay Matthews would say....just put a fathead on it!

MATTHEW D. wrote:

Wood'nCoal wrote:Nah, that should be good for a few more years.

But I'm afraid it might start rusting the boiler if I don't replace it .....

between you and your welder,it will be just like new.

LsFarm wrote:I wonder if anyone tries using a good quality RTV sealant on the rubber gasket for the coil?

On my AA, I had some pretty significant rust under the rubber gasket, but I didn't want to to a cut=out and reweld,
so I sandblasted the pitted surface, and LIGHTLY buttered the steel and the matching gasket surface of the old gasket.
I had and still have no leaks..

I shut down my boiler every summer, and only once gave the nuts on the plate a 'tweak' with a wrench.

I think that the good quality RTV [I use Permatex 'Ultra-Black' ] creates a waterproof seal that is NOT dependant on the 'crush'
of the rubber gasket to keep water from migrating between the steel and gasket.

Ive got to believe that with a new, clean steel surface and a new soft rubber gasket, that a THIN coal of Ultra-Black would assure
a waterproof seal for decades.

Just a thought. I don't think any other type of sealant would do the job, they all get hard, except RTV.

Greg L

I have used several new age sealants with pretty good results. There is a product at the auto parts stores called the "right stuff" that works real good if the surface is cleaned. That makes its own gasket. If I use a gasket, I coat both sides with the little tube of car t-stat rtv. Both ways have worked well.