Tannis Engine Heater

[andyb]

When I purchased the CTLSi, my plan was to get a Tannis heater, as it routinely goes under freezing in St. Louis during the winter.  My experience with Continental engines is that it's considered to be extremely hard on the engines to start them without a preheat if it's under 30 degrees or so.

 

Looking at the Rotax manual, it suggests that it's okay to start it (or at least within the allowable parameters) to start it at pretty low (sub-freezing temps).  Does this mean that the Rotax is okay starting in the cold without preheating?  What's a good guideline for how cold to start a Rotax that hasn't been preheated?

 

Andy

[Runtoeat]

Andy, I've put posts before in the forum for my method of preheating.  I use a 100 watt light bulb which is hung inside the engine compartment during the cold months here in Michigan.  I use the "old" incandescent safety coated "shop bulb", not the new, low energy ones.  This is positioned so that it hangs next to the oil reservoir.  I have a hook on the wire which catches the carb drip tray to keep the bulb in place.  To keep the warmth in the engine compartment, I put a foam plug in the radiator opening in my cowl and put an old blanket on top of the engine cowl.  About 1/2 hour before I fly, I place a hair dryer into the air inlet on my CTSW.  The light bulb is left on 24/7.  As Roger says, the Tanis is the "gold standard" but this method seems to really take the edge off the cold, keeps condensation away from the engine during cool wet days and allows good cold weather starts.

[Ed Cesnalis]

I used to get very hard starts with my first oil pan only engine pre-heater but it did fire up immediately.  Then I got the Tanis and the hard starts went away but It can be hard to start.  I"ve learned not to use any choke.

 

Now I have the soft start new ignition module and that coupled with the Tanis gives me a perfectly soft start.

[Tom Baker]

Is the Tanis approved for the injected engine?

[bseager]

The light bulb and blanket treatment worked great for my CTSW over a winter in the Canadian Rockies. Never had an issue starting even in -20 temps.

[Tom Baker]

Hi Tom,

 

The air intake points are all different. It may take Tanis some time to adapt to the 912is engine. They may not have even considered it. May be worth a call to Tanis to see. It should be an easy fix. The bottom case bolt is the same and the oil tank pad. It would just need the 4 screws on the air intake changed.

 

The reason I ask is because the OP has a CTLSi. We don't want him buying something he can't use.

[Rich]

I installed the Reiff heater for the 912 on my aircraft. It comes with a 100W pad for the crankcase and a 50w band heater (with thermostat) for the oil tank.

Although Tannis is the bench mark, I have no problems down to 15-20*F. It may be good for lower temps but I haven't had the need as yet. I have it plugged in the night before a morning flight and cover the cowl with an insulated blanket. I also use foam plugs for the oil cooler and radiator inlets.

 

The cost was approx. 25% of what the Tannis cost.

 

$229 for the 150w unit (recommended for PA winter temps by dealer)

$354 for the 250w unit.

 

reiffpreheat.com

[FastEddieB]

Roger (or whoever),

 

It's clearly an oversimplification to just say, "Engines are engines."

 

But...

 

We routinely start cars and motorcycles and ATV's and Snowmobiles and such down to temps in the teens, or lower, and don't worry about it much.

 

Can you articulate what it is, exactly, that makes the ROTAX fundamentally more sensitive to cold temps in this regard? 

 

I can see a legacy engine that uses 50w oil having a problem, but not so much with multi-weight oil with a "cold" rating of 10w. Seems like it should "flow" just fine.

 

I do try to pre-heat when below 30ºF, but would still like to have an understanding of why our engines are so different as to need it - the basic design just does not seem that radical.

[FredG]

Modestly priced Reiff heater works fine for my CT in the middle of Iowa winter (unheated hangar).  Reduces warm-up time dramatically.  Whether it reduces engine wear is unknown to me.

[FlyingMonkey]

Andy, I've put posts before in the forum for my method of preheating.  I use a 100 watt light bulb which is hung inside the engine compartment during the cold months here in Michigan.  I use the "old" incandescent safety coated "shop bulb", not the new, low energy ones.  This is positioned so that it hangs next to the oil reservoir.  I have a hook on the wire which catches the carb drip tray to keep the bulb in place.  To keep the warmth in the engine compartment, I put a foam plug in the radiator opening in my cowl and put an old blanket on top of the engine cowl.  About 1/2 hour before I fly, I place a hair dryer into the air inlet on my CTSW.  The light bulb is left on 24/7.  As Roger says, the Tanis is the "gold standard" but this method seems to really take the edge off the cold, keeps condensation away from the engine during cool wet days and allows good cold weather starts.

hair dryer warmup2_email.jpg winter nite2_hangar.jpg

 

I have what I call my "hillbilly pre-heater" similar to Dick's solution.  I have a Harbor Freight heat gun attached to a length of high-temp SCAT tubing.  I put the heat gun on LOW (high is 1200°F!!!) and put the tube up into the bottom of the cowl so the heat can rise up.  It takes about 30-45 minutes on a cold day* to get the entire engine compartment toasty warm.

 

This is an idea I got from others on the Sportpilottalk.com forum, it seems to work well.  It's not as fancy as the Tanis + dial in setup, but it adds no weight to the airplane and seems to work well if you don't mind getting to the airport with enough time before your flight to run the heater.

 

* FULL DISCLOSURE:  I live in Georgia and it rarely gets much below freezing.  A "cold day" here is about 30-40°F.  It gets colder, but not very often.

[Ed Cesnalis]

One reason IMHO to go for the Tanis is to preserve your sprag clutch.  I had many hard starts with my 1st engine pre-heater and eventually a hard start with rubber contaminating one carb the sprag clutch did fail and cost $900 to replace if I remember correctly.

[FlyingMonkey]

One reason IMHO to go for the Tanis is to preserve your sprag clutch.  I had many hard starts with my 1st engine pre-heater and eventually a hard start with rubber contaminating one carb the sprag clutch did fail and cost $900 to replace if I remember correctly.

 

Was your first system a Reims or something else?

[Ed Cesnalis]

I never knew the brand name, it was a single element stuck on the bottom of the oil pan.  It did make the engine warm to the touch but the starts were very hard.  The Tanis puts the heat where needed and the starts are soft but it doesn't fire immediately.

[Runtoeat]

Andy, my hair dryer is a little wimpy for this type of service.  Might do a "hybrid" system using your HF heat gun and light bulb! 

 

CT, you make a good case for the Tannis.  No doubt this is the Cadillac of heaters.  Have to say though, since installing my new Odyssey battery and using my light bulb and hair dryer, my sub freezing and above cold starts are quick with no "kick-backs".  I did need to find the "sweet spot" to set my choke lever.  Not an expert but I have to assume "kick-back" is a bad thing.  Must be one of the main causes for the early demise of the sprague and probably also must hasten the need to do a rebuild of the propellor gearbox.

[FlyingMonkey]

Andy, my hair dryer is a little wimpy for this type of service.  Might do a "hybrid" system using your HF heat gun and light bulb! 

 

 

Just be cautious, the SCAT tube gets really hot, even with my gun set on low.  I'd probably stick it in the bottom of the cowl like I do instead of in the inlet vent like you have it.  I'd worry about causing some heat damage to either the cowl or the fiberglass ducting.

[FredG]

My airplane is in an unheated hangar in Iowa. With a blanket over the cowling, the Reiff gets everything warm from the firewall forward. I would not be surprised if the Tanis makes for more even heating of the engine. Regardless, I find the Reiff very effective. If my plane was outside and subject to wind, it might be different.

[Ian]

Tania heats soaks the entire block and not just the bottom and oil tank like the Reiff.

 

She's one hot girl that Tania