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Posted

It is new engine time and while I am in there I want to do a cowl closure mod. I have considered the LASAR and ARI cowl closures. Does anyone have experience with either of these mods. Ease of installation? Ongoing maintenance/Problems? Are there other closure mods out there that merit consideration? The airplane is a 1965 M20E. Any suggestions or comments are greatly appreciated.


 


James


65 Super 21

Posted

I had the Lasar one installed during the previous annual, which was about 4 months ago. I have no experience with the ARI mod, but my AME sticks by Lasar regarding mods. Anyway, it looks really good and IIRC, it took them about 6 hours to fit the closure and if I look at it, it seems to be bit of a job. Mine also had to be spray painted after fitment to fit in with the rest of the cowling.


Before the anual, a friend and myself did the four course speed run and my Mooney averaged out at 138 knots. I did the same test again last Saturday. I was alone and it was very windy, so it was probably not that accurate. After the four runs, the speed averaged out at 135 knots! So, at this stage, I can't vouch for any speed increase in my own personal case but it definitely improved overall engine cooling substantially. I did both speed tests at 7500', WOT, 2500 rpm at 50 deg ROP. Highest CHT on Saturday was 362 deg. I normally fly at the same power settings but with the rpm at 2400 and then the higest CHT tops out at 345 - 350 deg. Before I had the cowl closure installed, high CHT's were usually in the 380 - 400 deg region.

Posted

I installed the Lazar cowl mod several years ago on my 75 F and found absolutly no bennefit except for looks. I did the 4 direction speed test before and after and there was no gain or loss. Recently, I had Top Gun install the ARI cowl closure and after the 4 direction check I found that I gained 7 kts airspeed and 4 kts GPS ground speed. I was truly impressed. I've always had good cooling and it seems to be the same with both closures. With the Lazar closure I would climb out at 700-800 FPM and with the ARI I'm now climbing out at 1,000-1,200 FPM. The only problem is with the ARI I'm getting some reflective cracking in the inlet areas where the fiber glass is rivited to the aluminum. Top Gun is currently working on this issue and hopefully will be resolved this week. It's a big issue with me right now since I've just had the plane painted at Santa Maria (KSMX).


Good Luck, Pilot Bob

Posted

I've got the lasar cowl mod on my 65E.  Ditto the better cooling and no significant speed increase. If I had to do it over, which I probably will, I'd spend the extra money on the ARI mod.  It just has a more professional appearance making it look similar to the 201. The lasar mod just transforms your "guppy mouth" into a smaller one.

Posted

Was the lasar mod fiberglass as well? How bad is the cracking, I sure hope it did not ruin your paint in that area. Absolutely beautiful paint job you did, where did you have it done?

Posted

Hello   KJATCt


PilotBob had his Mooney recently painted at ArtCraft in Santa Maria, CA. Not far from you.  Many of us Mooney owners can  vouch for the awesome paint jobs these folks are producing.   Please see the following threads on MooneySpace.com for more information on this subject.  I am happy to spread the word for this.  Please feel free to contact me.


"I'll be painting my airplane soon....."  and "Well She's done....and boy is she red! :) ".

Posted

Does anybody know where there might be any pictures of the ARI cowl closure to be seen? I went all through their web page, but there's no pics there - not good for business I would think.

Posted

Interesting! ARI used to have full before and after photos of their enclosure on  their site.  Here is a photo of PilotBob's new ARI enclosure as his Mooney was coming out of the paint shop.  Not to take away from the LASAR cowl enclosure, which in my opinion, certainly does make the wide mouth of our vintage Mooneys look better. 

post-291-13468137878875_thumb.jpg

post-291-13468137880773_thumb.jpg

post-291-1346813788111_thumb.jpg

  • Like 1
Guest Anonymous
Posted

I have the ARI cowl and only have one knock.  The four flat head machine screws that join the rear and front corners of the upper and lower cowl wear the fiberglass over time, and it becomes necessary to use dimple washers with them.  (I noticed that piperpainter's mewly painted bird had them also when I walked around it, nice stailnless ones.)


The screws at the prop hub and front mount points are fine -- only the four at the cormers wear.


RFB


 

Posted

Quote: PilotBob

I should have mentioned that the ARI kit also includes a new prop. bulkhead and polished pointed spinner.

Posted

Quote: Lood

I would just like to confirm that I understand you correctly. If you do the ARI cowl closure mod, is it a new prop, bulkhead and spinner part of the kit and compulsory, or can the cowl closure be done with an existing prop assembly?

I would seriously consider replacing my Lasar closure with the ARI, but if the latter required me to replace the prop, etc. it would not be finacially viable for me.

  • Like 1
Posted

I am bit confused now... I fly a 1967 M20F and have been considering a cowl closure mod. My main objective is lower CHTs. My engine runs pretty cool but at max weight in the summer cylinder number 3 hits 400'F in the climb initial quite frequently on the EDM 700, at which point I lower the nose. My other CHTs go up to 360-370 max. In the cruise I get 310-320 for 1,2,4 and 340-350 with number 3. Bear in mind the number 3 is where I had to installed a bayonet probe so it might be reading higher anyway just due to probe location. The factory gauges stay in the green at all times. So I might just be paranoid, there might not be a need for it.


Would I benefit from a cowl closure mod and do I need it? I can't afford a full cowl, but if it drops the CHTs, a cowl closure mod might be an option. We seem to have drifted in this discussion from cowl closure to full cowl mod. How do the cowl closure mods from SWTA and Lasar compare? I can't fit an ARI mod as I don't think it ever got signed off in Europe while the other two have.


 

Posted

Podair, that's exactly why I did the cowl closure mod. My primary reason was to improve CHT's and on the side, I hoped to gain a bit of speed. In my case, the speed part did not really happen, but the CHT improvement definately did and I would like to think that the improvement on my engine's oil temperature is a direct result.

Posted

Well I guess it is time I chimed in as I have a lower cowl enclosure from Lasar which was installed before I bought the airplane I currently have. On my previous Mooney 76  20F I started with an ARI cowl modification as is shown in Pilotbob 's conversion. After 10 hours of flight I experienced a loud bang in flight over Nanaimo BC. , the engine seemed to stop for a second then carried on. I intially declared an emergency and I got clearance to emergency land at Nanaimo. After checking all the engine parameters being normal and no loss of speed I decided to abort the emergency and return to my home airport in Qualicum Beach. After landing I was blown away with the damage to the front cowling as well as the prop I wondered how it flew after what I saw.  The prop ends were bent back about three inches and the front cowling was shredded. What happened apparently, after my AME checked it out was an anomaly as the backing plate had cracked and a piece about the size of a lemon was missing. What happened was the cracked piece flew out and got caught in the prop which then caused the cowling damage. Fortunately my insurance covered the damage and went after ARI for a counter insurance claim based on the backing plate being factory defective. I decided not to get a replacement from them and and paid the balance of the cost given to me from the insurance company for a SWTA FIBREGLASS cowling package. After this was installed I found the airplane to certainly cool more efficiently and to actually be somewhat quiter in flight.


In all fairness, ARI was most responsive to this mishap and supported me all the way in getting it covered by insurance.


So, the $8000 plus question what would I do again... I would go with the SWTA cowl mod even though it is more expensive because it is much more refined. I am seriously contemplating getting my lower cowl mod replaced with SWTA in the next year.


I trust this story is worthy of some contemplative thought from those of you so inclined to modify your airplane


Philip

Posted

Quote: Lood

I had the Lasar one installed during the previous annual, which was about 4 months ago. I have no experience with the ARI mod, but my AME sticks by Lasar regarding mods. Anyway, it looks really good and IIRC, it took them about 6 hours to fit the closure and if I look at it, it seems to be bit of a job. Mine also had to be spray painted after fitment to fit in with the rest of the cowling.

Before the anual, a friend and myself did the four course speed run and my Mooney averaged out at 138 knots. I did the same test again last Saturday. I was alone and it was very windy, so it was probably not that accurate. After the four runs, the speed averaged out at 135 knots! So, at this stage, I can't vouch for any speed increase in my own personal case but it definitely improved overall engine cooling substantially. I did both speed tests at 7500', WOT, 2500 rpm at 50 deg ROP. Highest CHT on Saturday was 362 deg. I normally fly at the same power settings but with the rpm at 2400 and then the higest CHT tops out at 345 - 350 deg. Before I had the cowl closure installed, high CHT's were usually in the 380 - 400 deg region.

Posted

So I have decided to go ARI on the cowl. Speed test N S E W avg GS 23" MAP 2400RPM 5500' MSL about 350 CHT power boost off 148.7 KTS. That is before mod, I will do the mod this month or next as I am resealing my tanks now. I will post again with speed and temps after mod.

Posted

out of curiosity, do you have a multi probe EGT?CHT fitted? What kind of temps do you get? I have an EDM 700, and had to fit a bayonet probe for cylinder 3 where the factory probe is fitted. Cyl 3 is the one I get the highest CHT readings, on average 30-40 F higher than the other ones and I hit 400 on it only in max weight climbs in 30deg plus temperatures. So I am wondering if I am overconcerned and the CHT is not really an issue as the other ones are in the mid to high 300 at worst and the factory one is still in the green, and even if so, it is only an issue in hot weather at max weight in the summer.

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