Mini 500 forum ??

Dave, did you buy this one from Laurie up in Queensland?

Cheers, Francois
Hello Dennis, just to let you know I have just purchased serial no. 11. It has 330 hrs TT, has a new 582 fitted & is now & has always been a great little helo & never had a moment of trouble. I look forward to keeping it alive & well into the future.
 
Greetings from Abu Dhabi Rotorcraft Enthusiast!

I hope all here has been well. I have been too busy to participate in the forum this past year with my project here. Wow, already one you have passed, but with great results.

I do have a question for anyone that can remember;

What was the brand and grade of the oil we were using in the Mini-500 transmissions? I'm in an oil-rich country, and damned if I'm having trouble with the oils all foaming up in my gearboxes!

Bryan, you are all-remembering on the Mini-500 stuff.

Any help would be appreciated. Hope all here have a great New year!

Sincerely,

Dennis
 
Greetings from Abu Dhabi Rotorcraft Enthusiast!

I hope all here has been well. I have been too busy to participate in the forum this past year with my project here. Wow, already one you have passed, but with great results.

I do have a question for anyone that can remember;

What was the brand and grade of the oil we were using in the Mini-500 transmissions? I'm in an oil-rich country, and damned if I'm having trouble with the oils all foaming up in my gearboxes!

Bryan, you are all-remembering on the Mini-500 stuff.

Any help would be appreciated. Hope all here have a great New year!

Sincerely,

Dennis
Best I could ever determine "almost" got me to the bullseye of learning what was in your bottles, so I gave up and used the Robinson stuff.
 

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Best I could ever determine "almost" got me to the bullseye of learning what was in your bottles, so I gave up and used the Robinson stuff.

Thank you, Bryan,

I did some more digging too. The gear oil we switched to was Shell Spirax S6 AXRME 75W-90. It came in 5-gallon drums and cost too much for the customers, so we bought it in 55-gallon drums and rebranded it so we could sell it at a lower cost to everyone.

It was much better than the first oil and lowered the temperatures as well.
 
To all you clever guys out there, the recommendation above is to use Shell Spirax S6 AXRME 75W-90 oil in the MRT. It is a full synthetic API GL-5 type product. Would one say that this specific product, due to the possibly unique additives Shell adds to it, would have a markedly different performance that a similar seemingly equivalent product like the full synthetic Penrite Pro Gear 75W-90? How about the mineral oil blended equivalent semi-synthetic Penrite Trans Gear 75W-90?

All comments welcomed.

BR,

Francois.
 

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If anyone needs a PEP exhaust, I have one I don't need. It needs media-blasted and painted...or JettHott coated.
$100 plus shipping, needs no packaging, just UPS label.
 
Hi Francois

Racegear WA have the Swepco ex stock Perth. It is not cheap. This stuff is used by high end race types.

Have you tried your local Robbie dealer or mechanic?

Penrite do not provide enough tech detail to make a valid comparison. However, since the Penrite is a full synthetic and the Swepco a full mineral, I doubt there is any "equivalence".

How much is the gearbox worth?


Cheers


Miles
 
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Hi Francois

Racegear WA have the Swepco ex stock Perth. It is not cheap. This stuff is used by high end race types.

Have you tried your local Robbie dealer or mechanic?

Penrite do not provide enough tech detail to make a valid comparison. However, since the Penrite is a full synthetic and the Swepco a full mineral, I doubt there is any "equivalence".

How much is the gearbox worth?


Cheers


Miles
Thanks, but at $260 a US Gallon, is it really worth it excluding the synthetic alternatives? I appreciate everyone's input, my hesitance is that I'm going to run in a rebuilt transmission. This means putting in very expensive oil, and dumping it after a couple of hours of running in. Does it not make economic sense to use a cheaper synthetic to run it in, seat the gears well, then drain, flush and put in the dear stuff?

Cheers, F.
 
Francois, I would feel AOK "running-in" your gearbox with any "extreme pressure" 90W gearbox oil. I'd even feel good hovering around with that oil. Once your butt is in it at 500' flying around, I would have drained it and replaced it with the pricey stuff. Keep in mind, and weigh-n-decide for yourself that 100% synthetic is somewhat hygroscopic and unless you operate the transmission AT FULL OPERATING TEMPERATURE, FREQUENTLY, moisture infiltration may cause rust-bloom to form on bearing races and balls and on the contact faces of the gear teeth. If the gearbox will be sitting unused for an extended length of time, pure mineral oil needs to be all over the insides as a moisture barrier.
 
Francois, I would feel AOK "running-in" your gearbox with any "extreme pressure" 90W gearbox oil. I'd even feel good hovering around with that oil. Once your butt is in it at 500' flying around, I would have drained it and replaced it with the pricey stuff. Keep in mind, and weigh-n-decide for yourself that 100% synthetic is somewhat hygroscopic and unless you operate the transmission AT FULL OPERATING TEMPERATURE, FREQUENTLY, moisture infiltration may cause rust-bloom to form on bearing races and balls and on the contact faces of the gear teeth. If the gearbox will be sitting unused for an extended length of time, pure mineral oil needs to be all over the insides as a moisture barrier.
Thanks Bryan, comments appreciated. The possibility of hygroscopic properties of a full synthetic oil is not something I had considered before.

Cheers, F.
 
Thanks Bryan, comments appreciated. The possibility of hygroscopic properties of a full synthetic oil is not something I had considered before.

Cheers, F.
I see your screws arrived.
 
Do you still have pep exhaust? If so can you please send me a pic?
Yes I do. It's in good shape but it was painted bar-b-que grille black when new, and has never been repainted so it's surface rusty, external only. It has been "contoured" a little bit in the areas where they got real close and started vibrating against the Mini-500 frame.
 

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