CTSW ANTIFREEZE ON FLOOR OF HANGAR

[Isham]

This morning if found an area of antifreeze on the floor.  Dripped from the aft left cowling area.  I did not see anywhere there were any leaks on the cylinder top seals or hoses on the radiator.  Photos show the radiator, right of the dashed line looks wet.  Outline of the floor spot is the area where antifreeze appeared.  (Most spots on the hangar floor were from my old Cherokee.)

Is it common for a radiator leak or could something else be leaking that I am just not seeing?  The airplane has about 400 hours TT. 

If it is the radiator are there any repair options or just buy new?

[Tom Baker]

It is not uncommon to have a coolant leak when the temperatures get cold. The most likely spot is the larger coolant hoses, then anywhere there is a screw type hose clamp. Pull the cowling and tighten all the hose clamps. Other issues are leaking water pumps, and fittings in the cylinders. You have them on both top and bottom. There are other possible issues, but those are the most common.

[Animosity2k]

I get this every winter and have learned to deal with it. Was never quite able to find the culprit of the leak however it only leaks when its heavily filled. Once the coolant level gets closer to the "min" line on the container I notice it stops leaking. 

[Isham]

Does your make 1/2 of the radiator wet in the winter?

I pulled the upper cowl and could not see any engine or hose leaks.  I will pull the lower cowl next trip to the hangar. 

Thanks.

[Roger Lee]

From the picture the coolant is up front and on the right side so this isn't from the weep hole. This should mean that your metal tubes of the radiator are contracting in the cold which causes a loose clamp and coolant comes out. Tighten all your hose clamps on the coolant hoses when the engine is cold. The other area to look for is the 17mm coolant constant compression hose clamps.  The clamps should be up close to the metal flared end under the hose on the meat tube. If the clamp is too far away the 17mm hose can leak. You can feel the flared metal end under the hose. Make sure each clamp is slid up right next to it, but not on top of it. 

 

The weep hole on the bottom of the water pump can leak a tad during cold weather, but not usually more than a tablespoon or so. This is caused by different materials at the seal that expand and contract at different rates, but a  big cup worth is not normal.

 

 

[Tom Baker]

1 hour ago, Isham said:

Does your make 1/2 of the radiator wet in the winter?

I pulled the upper cowl and could not see any engine or hose leaks.  I will pull the lower cowl next trip to the hangar. 

Thanks.

I have not known of one of these radiators leaking. Take a tissue and see if you can determine what is causing the radiator to look wet. Most of the time when I see wetness in that area I suspect someone spilled some oil during an oil change or checking the magnetic plug. 

Where was it wet on the inside of the bottom cowling? Was there coolant on the flap under the radiator?

[Warmi]

When it gets cold , I get the same type of leak but generally only limited to maybe a tablespoon or even less... it never happens during warm months , only during winter.

[okent]

+1, same thing.  tablespoon on really cold nights.

[Animosity2k]

1 hour ago, okent said:

+1, same thing.  tablespoon on really cold nights.

Agreed probably a tablespoon or so, but it will happen many times throughout the winter.

[Skunkworks85]

1 hour ago, okent said:

+1, same thing.  tablespoon on really cold nights.

+1

[Isham]

This morning there was only a couple of tablespoons.  I could not see any leaks with the cowl off but did tighten the hose clamps.  I assume this amount is nothing to worry about. Thank you for our help.

[AGLyme]

Well, I had the same condition last winter.  FD USA suggested that I add 2 more worm clamps.  I did and the drops stopped.  The spring clamps that come from the factory aren’t tight enough.  Use the worm clamps that do not dig into the rubber hose.

[GrassStripFlyBoy]

Nearly every time I have the cowl off I tighten the hoses, just a tick, but keep on them.  We've had some cold temps here in MI being Dec now, and I've yet to see even a drop start.  Last year being a new owner I was going through this learning curve and would see a small amount with temp swings.

I also wonder if the rubber being new every five years has to go through cycles, takes a compression set, relax a bit, re tighten the clamps, etc - and now I'm in the sweet spot where things have settled in to staying tighter?  Either way it's not been much hassle, I just bought a jug of Dexcool as the reservoir is approaching the min level after what is now ~ 150 hours and 15 months since I bought it.  

[Roger Lee]

The new hose will take a set, but if tightened at 100 hrs. usually never gets any smaller. The issue here is the aluminum tubing in cold temps. It shrinks just a tad, but when warmed back up expands a tad again and the drip stops. I see and hear about it all the time. Most of the time people don't put the spring clamps in the right place. The clamp should go up to, but not on top of the flare under the hose on the aluminum tube. Putting the clamp there add extra pressure right at the flare against the hose and stops most all leaks. If mechanic's used a checklist or paid more attention to detail during an inspection they would put a wrench on all wormdrive clamps to check them.

The other place toy will get some leakage is from the water pump weep hole in cold weather. The pump seal is made up of three different kinds of materials and they all shrink and expand at different rates. When the shrink they can drip a tablespoon or two behind the front tire where it exits the cowl. No way to stop this and it isn't a big deal.

The best advice I can give is to "Move to a warmer climate".  

[procharger]

I keep a 60 watt light bulb in cowling and a blanket around it and

have no leaks no light bulb I will have a little leak like  you guys

have. Normal

[Animosity2k]

21 hours ago, Isham said:

This morning there was only a couple of tablespoons.  I could not see any leaks with the cowl off but did tighten the hose clamps.  I assume this amount is nothing to worry about. Thank you for our help

I would say this is nothing I easily have 4-5x this coming out... I had my AP look at it last year and they could never figure it out ;/ I just fill  it back up when it gets low. 

[Animosity2k]

16 hours ago, Roger Lee said:

The new hose will take a set, but if tightened at 100 hrs. usually never gets any smaller. The issue here is the aluminum tubing in cold temps. It shrinks just a tad, but when warmed back up expands a tad again and the drip stops. I see and hear about it all the time. Most of the time people don't put the spring clamps in the right place. The clamp should go up to, but not on top of the flare under the hose on the aluminum tube. Putting the clamp there add extra pressure right at the flare against the hose and stops most all leaks. If mechanic's used a checklist or paid more attention to detail during an inspection they would put a wrench on all wormdrive clamps to check them.

The other place toy will get some leakage is from the water pump weep hole in cold weather. The pump seal is made up of three different kinds of materials and they all shrink and expand at different rates. When the shrink they can drip a tablespoon or two behind the front tire where it exits the cowl. No way to stop this and it isn't a big deal.

The best advice I can give is to "Move to a warmer climate".  

Roger any good photos of where these clamps are located / where to tighten them up at? My local non rotax AP could not fix this issue for me last year and I get 3-4x what everyone else is posting. Typically I just fill it back up. 

[Roger Lee]

The worm drive clamps are on all the 1" hose and there are a couple on the 17mm hose usually on top, but someone may have added some under the cylinders. The spring clamps are on all the 17Mm hose and not 1". Another place you may be leaking is where the 90 Degree elbow screws into the top of each plate on top of each cylinder.

[AGLyme]

Take the bottom cowling off.  Tie a Kleenex around where the coolant hoses meets pipes etc... use cellophane tape around the Kleenex.  In the AM after a cold night, chances are you will find the culprit leak.  My coolant is (BMW motorcycle) blue colored coolant. 

[Animosity2k]

On 12/11/2020 at 8:58 PM, Roger Lee said:

The worm drive clamps are on all the 1" hose and there are a couple on the 17mm hose usually on top, but someone may have added some under the cylinders. The spring clamps are on all the 17Mm hose and not 1". Another place you may be leaking is where the 90 Degree elbow screws into the top of each plate on top of each cylinder.

Are these 90* elbows easily visible when I take the cowling off? I may try tonight to just go through and tighten every clamp in there. 

[GrassStripFlyBoy]

Here are some reference pic's, the joint between the tube and flange is often the leak:

 

The bottom spring clamps are here, these need to be right up to - but not on top of, the bump on the inner tubing:

[Animosity2k]

So I guess I have a lot more leaking then most of you. Does the bottom cowling need to come off to get to these screws/nuts? Today I tried to remove the bottom cowling (never done it) and found myself in a total bind now. After three hours of trying to get it back on / or completely off I can't get anywhere. It appears the front tire needs remove to take it off? And when I try to put it back on and just deal w/ the fact I have coolant leaking (figure I can always fill it) I then run into the issue of not being able to get the air hose to line up as photo'ed below. Any tips? I was hoping to fly Wednesday (first nice day in 2 months that I'm off) and now I've got the thing apart and can't get it together :(

[AGLyme]

Ps: I have the LS with an injected motor but carb motors have less junk attached so it should be easier I think for carb planes.

things to do before you take the bottom off:

1) unscrew the TOP clamp of the orange air intake hose and remove only that part of the hose from the engine.  You are left with a short orange hose attached to the bottom cowling.

2) unplug the landing light.  Obviously the landing light remains attached to the bottom cowling.

3) unplug a black plug electrical plug near the battery.  I believe it is a sensor for the air intake... I forget.  It will be obvious that it needs to be unplugged... and the balance of the wire stays with the bottom cowling.  This step is the absolute hardest step for me because getting the plug unplugged is a pain.  Get your iPhone in there and take a photo of it.  You need to depress a plastic tab to get the plug unplugged.  I use needle nose pliers and it now takes seconds.

4) unscrew the fasteners.

when removing or re- installing the bottom cowling for the first time, have someone with you to hold it lightly as you maneuver the cowling.  You can obviously see where the parts have to go... when re installing I put it under the engine on top of the front wheel of course and get the muffler through the hole... then work on the air intake.  That’s what I do and as I always say, if I can do it anyone can. 

I have not removed the front tire pant.

I am going to the airport tomorrow happy to face time with you... and show you what I do with mine.

Andrew 

 

 

 

[Tom Baker]

The bottom cowling should come off fairly easy. For the CTLSi there is a hose to disconnect from the throttle body. Likely an orange duct on the right side of the cowling towards the rear. The landing light wire will need disconnected on the left front. There are 6 fasteners to be undone, 3 on each side on the rear of the cowling. With all of that undone you should be able to get the fasteners to come loose. Lower the cowling to clear the exhaust pipe, and you may have to tilt it a little. If you have the Frankenstein bolts on the landing gear you might have to pull the cowling to one side to clear the bolt, then to the other side. Also it looks like you might be a little tight on the spinner. Just be patient, and not to rough. It will come off.

Also that grey duct on the cowling goes inside the tan colored duct for the air cooling. You might need to reach inside the hole in the front of the cowling to help line it up.

[AGLyme]

I have the Frankenstein bolts... minor factor.