Sump heater! Yeah...toasty!

[Brantel]

I finally instaled my sump heater that I have had sitting on the shelf for 4 years.

A couple weeks ago I finally installed it and gave the epoxy it came with a week to cure properly before using it. I started out only using it when I was there just to make sure it was not going to burn down my airplane and hangar. It seems to really get hot locally but I guess that is the point.

Anyway fast forward to this past weekend...After I installed and tested my P-Mag, I left the heater on and went back over to the airport and checked on it last night. It has been running for 4 days and all is well.

I did not have a blanket on the cowl but I did plug the front inlets with two T shirts.

OAT = 32°F
Oil Temp = 78°F (sensor only, no turning the prop, no flow, up top in the normal sensor location)
Carb Temp = 88°F
CHT = 69-72°F
EGT = 58-62°F

The built in thermostat on the heater is fixed at 160°F max I think so the carb temp probe which is really close to the heater seems to prove that that is working OK.

Last night I folded an old sleeping bag and placed it on top of the cowl. This should really help.

I know that some have said that these heaters can cause condensation and problems when used long term but I cannot see how when I can get the entire area inside of the cowl up to these temps. Our average cold temps are not that low so we are lucky in that regard. I imagine that somewhere that has much lower average temps might see a problem but I do not think here in East TN it will be a problem. The other thing is that I bet the ones that do have problems are not flown many times per month like my plane is so that could allow condensation to build up in there.

I plan to check it again after a few days of cold snowy weather and see how it is doing with the blanket on there....for now I plan to leave it on 24x7!

The reason I want to leave it on is because it is a 40 minute drive to the airport and I rarely have much notice before I go flying. I don't have money to spend right now on a cellular activated switch so that option is out.

Here is the heater that I installed:
http://www.mcfarlane-aviation.com/Products/?ID=3769206&CategoryID=128

 

[longranger]

Be careful of condensation:

http://www.cessna170.org/forums/viewtopic.php?f=2&t=6972

 

[Greg Arehart]

Brian,

Remote cell switch doesn't have to be expensive. Here's my solution:

http://www.vansairforce.com/community/showthread.php?t=38729&highlight=remote

greg

 

[pierre smith]

Our solution....

...was to buy a timer for $12 from the local hardware store. Our temps are close to yours and if we're going flying the next day, I set it to come on at midnight. The Reiff double-pad system has the block and oil over 70 deg by 9:00 a.m. then.

Best,

 

[allbee]

I have the Reiff system, that's wraps around the cylenders and a heater on the sump. I keep mine plugged in 24/7. been doing this since day one, I now have 450hrs since april 09. I plug no inlets, I cover no cowl. I've changed the oil during my plug in times and absolutely no condensation in the engine. I also open the oil door and undo the dip stick. Now with that said, the other day I went out to fly and the outside temp was 5 degrees, the oil temp after startup was 75degrees, I thought that was pretty good for the cold, again there is nothing done to the airplane except having it plugged in. I am hangared with no heat. I use this method all the way up to 45degrees outside and have done it at 60degrees, the highest I've seen the oil temp at startup is 100degrees. I have no thermostate on the system. Now I will say that I generally fly everyday, but have gone as much as 4days with out flying and the plane plugged in.

I have another advantage to this system and having it plugged in all the time. I have a water bottle, just a little 12ounce plastic bottle used for water when you buy it. I keep it filled so I can have a drink every 15min when flying. It never freezes, even when it was 5 degrees out the other day, my bottle of water was nice and cold, but not frozen. I throw it down between the seats, just behind the manual aileron trim.

 

[Sam Buchanan]

Be careful of condensation:

http://www.cessna170.org/forums/viewtopic.php?f=2&t=6972

That concern has been pretty much addressed by field history when planes are flown fairly frequently and the engine is insulated so the entire firewall forward stays warm. Here is a good article by Mike Busch:

http://www.avweb.com/news/maint/182846-1.html

And a quote from that article:

"There has been considerable controversy about whether or not it's a good idea to leave an electric preheating system plugged in continuously when the airplane isn't flying. Both TCM and Shell have published warnings against leaving engine-mounted electric preheaters on for more than 24 hours prior to flight. However, these cautions are really applicable primarily to single-point heaters such as oil pan heaters."

"The concern of TCM and Shell is that heating the oil pan will cause moisture to evaporate from the oil sump and then condense on cool engine components such as the camshaft, crankshaft or cylinder walls, resulting in accelerated corrosion of those parts. However, if the entire engine is heated uniformly by means of a multipoint heating system, or because the engine and propeller are covered with insulated engine and prop covers, such condensation is very unlikely to occur."

"In fact, using an insulated cover and a multipoint preheating system that is plugged in continuously is one of the most effective methods of eliminating internal engine corrosion, particularly if the aircraft is kept in an unheated hangar rather than outdoors. If the entire engine is maintained above the dewpoint, condensation simply cannot occur."

My experience with ten years of 24/7 preheating has been positive with no indications of engine corrosion.

 

[Ron Lee]

I use my sump heater starting the evening before or about 4-5 hours if I use my timer. I live five minutes away from the plane.

I also use my engine dryer system continuously.