Try a softer insulation material , mount the pump outside in a insulated box . Make sure you use thick material. Do not mount it on the case. The rubber you used is to hard and as somakes little difference. Good video though, shame it was not as good as you inticipated it to be.

haha, you made it worse

A word of warning you have fitted your exhaust muffler indoors, these are poorly assembled and leak carbon monoxide fumes plus there is a moisture drain hole.

Sorry but I’d call that a 100% fail.

The best way to get over this noise is freezing cold.

fill the box with expanding foam

You need rubber mounts from the box to the sheet metal. the sound is amplified by the sheet metal try not to mount the box with bolts just hanging and check for noise level.

i dont understand why people dont materials dedicated to sound deadening, such as foam. the hard object will vibrate the sound you need to dampen it

😂😂 Its not much difference, fair play for trying. There an absolute nightmare 😫 specially when trying to sleep in your van. Like Chinese torture 😂

Hey mark some one knocking at your door

Surprising there wasn't better results. I would've bet that would wrork. A big thumbs up for all the work!

Thanks for the thought provoking video. I think much of the noise it due to the pipes tapping on the case and other rattles. I have a similar heater and I love it iny small van

I did this using roof and gutter neutral cure silicone.

Great idea using the box but if you had used acoustic wadding or quilting rather than hard rubber it would improve the sound reduction hugely. In the example here the pump sound transfers easily through the rubber to the outside box and onto the outer heater casing so not much if any change. Enjoyed the video and thanks for posting

My Dad had some success quietening the noisy pump by wrapping it in neoprene foam, then dangling it from small rubber bungies which helped isolate it from the heater body, I mean it still clicks but not much of the sound makes it from the pump to the rest of the heater. The weird thing is, I've got a Japanese paraffin heater which uses a similar solenoid dosing pump, but for some reason that makes no discernible noise at all.

I have been meaning to pick up some duct seal, the stuff like heavy duty modeling clay.

The silencer has a hole in it to let out condensation so should be rotated 90 deg to let tit drain. It will also let out exhaust gasses. Therefore, place the silencer outside and live longer

Just thought I'd mention that the muffler should be mounted vertical with the drain hole facing down and the lowest point of the exhaust system

What I did was bought a silicone mold making kit. One that xxx toys could be made of soft. An taped the hose ends. And the plug part. An just got a Tupperware container. And encapsulated the pump. Than with a razor blade. Extracted to my tape areas to expose the plug an each hose end. Plugged it up to the hoses an plug. An just stuck it in the heater an closed it up.

Try closed self foam insulation like you use in HVAC. It’s black in color and you can get it in different sizes. You should be able to simply wrap the insulation around it and zip tie it to keep it closed all done, faster and cheaper.