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M20J ram air broke - any point in fixing it?


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in my x-country flight, I tried to use it Ram Air above 6,000 ft as recommended by POH. And… I should know better, it broke - most likely the line. Now it hangs loose and opens up in the flight by itself. 

Is there an easy fix for this? Or looking at some older post, should I even try to fix it instead of closing permanently? 

Thanks, Dominik

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A lot of people safety wire it closed and placard inop. 

Mine is fully functional but provides about 1/10 of an inch MP. I use it only to feel better about myself if flying into a stiff headwind. I've never noticed any real performance increase.

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I would close it off, over time the gasket wears and you get grit into the engine intake.  It doesn't really help at all anyway.  The downside of closing it off is having to fiberglass over the opening and get it painted, a pain but worth it in the end.

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Lasar sells the ram air delete kit.    We put it on my airplane after the ram air got janky, and I see zero reason to maintain the ram air system on a M20J, since it is essentially useless and adds the risk of dirt, water, ice, dust, etc., going straight to the fuel servo and into the engine.    The kit includes the parts to perform the deletion on the intake box, and you're on your own for plugging the hole in the cowl, which is a pretty easy fiberglass patch task.

https://lasar.com/service-instruction-kits/service-instruction-kit-si20-093-001

Personally I think it's one of those must-do mods on a J model.   The factory apparently thought so, too, as the ram air system was dropped altogether on later J models.

 

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3 minutes ago, bluehighwayflyer said:

With your E it actually helps, due to the vintage Mooneys’ poorly designed primary induction system, so you might want to keep it functional.  

Other than one trip thats going to take me above 10, i rarely go up to 6 as it is. Texas and towards the east is pretty flat. 

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24 minutes ago, Smiles201 said:

Best solution is very reasonably priced Whelen cowl, which has a modified 'scram' air injection. Check it out;

https://flywat.com/products/super-201-carbon-fiber-cowl-mod


That’s pretty interesting…

WAT bought up all things Lopresti… mostly for their HID landing light aka Boom Beam.

The price on the cowling doesn’t seem to have been updated in 20 years…

The website says….  Made to order… so there isn’t a whole lot of NOS holding that price stable…

Getting a new Lopresti cowl at that price would be great…

20 years ago, that was a new car price… :)

Call before ordering… if they adjust the price to today’s new car price… that would be bad…

Roy LoPresti made some wonderful parts for Mooneys…  He was THE Speed Merchant…

Best regards,

-a-

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38 minutes ago, Smiles201 said:

Best solution is very reasonably priced Whelen cowl, which has a modified 'scram' air injection. Check it out;

https://flywat.com/products/super-201-carbon-fiber-cowl-mod

That is the LoPresti Cowl and it is a great modification.  When it was put on my plane, I got significant increase of 8+ KTAS.  The ram air on that cowling gives a true 1.25" increase in manifold pressure.  It also significantly increases the ability to pre-fight since there is a large access door on both sides of the cowling which spans the baffling so you can easily see the entire top of the engine.  I can reach in through the left door and grab the magneto to make sure it isn't coming loose.  Additionally, the parting line is lowered so when removing only the top cowling you have great access for routine maintenance.

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1 hour ago, Mooney Dog said:

This is a big fear with my E. Hopefully I don't have to worry about it for some time, but I will most likely close it off in time. 

On the E I wouldn’t. It gives you almost a full inch of extra mp at altitude. 

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7 hours ago, ArtVandelay said:


And that’s available where and how much?

Rajay? For whatever the scrap dealer asks for when you find one in a junk yard. At least one person here has done exactly that. Can't remember how he got the STC but he cobbled up all the rajay parts from junk yards.

 

-Robert

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8 hours ago, ArtVandelay said:


1. It’s $16,000.
2. Doesn’t fix OPs problem.
3. Ram air doesn’t boost performance on the J anyhow.

While it is expensive, it will fix the OPs problem since it replaces the entire ram air system with a different system that actually work and is easy to maintain.  On my 1980 M20J, it provides 1.25" additional MP

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1 hour ago, RobertGary1 said:

Rajay? For whatever the scrap dealer asks for when you find one in a junk yard. At least one person here has done exactly that. Can't remember how he got the STC but he cobbled up all the rajay parts from junk yards.

Some company called M-20 Turbos was selling new Rajay kits a while back, not sure whether they still exist?

Decent oldish article in AC about this:  https://www.aviationconsumer.com/misc/two-turbo-retrofits/

 

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1 hour ago, toto said:

Some company called M-20 Turbos was selling new Rajay kits a while back, not sure whether they still exist?

Decent oldish article in AC about this:  https://www.aviationconsumer.com/misc/two-turbo-retrofits/

 

When Mr. Sandman died, so did the company. The kit was $35K back in the day. Luckily, all the components are supported and all the other parts are repairable.

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I would not be surprised if what broke was the axel around which that ram air butterfly turns. Not a difficult part to replace. 

Does the SI gives instruction on how to disactivate the RAM air annunciator when you remove it ? remove the annunciator or just remove the bulb ?

 

 

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25 minutes ago, OR75 said:

I would not be surprised if what broke was the axel around which that ram air butterfly turns. Not a difficult part to replace. 

Does the SI gives instruction on how to disactivate the RAM air annunciator when you remove it ? remove the annunciator or just remove the bulb ?

It just says to remove the switch, which will prevent the annunciator from illuminating.   I think I marked the wire in case I wanted to use the annunciator lamp for something else, but haven't.   It still lights up if I push the test switch.

 

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Maybe I’m missing something? Why not just leave it closed and never mess with it? If it’s not used does it wear out from vibration etc?

If not why bother going through the trouble and expense of removal, especially the glass and paint part?

 

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