Reversing gears in XR's?

[JupiterSunsation]

A buddy was told recently since he has almost 300 hours on XR's that he should take the drives to a well known shop and "reverse the gears." The idea behind it is to create a fresh set of gears since they are going to be spinning in the opposite direction.

I had never heard of this but has anyone here done this and what were the results? Is the cost of removal/repair worth the "reversal"?

 

[Geronimo36]

I've heard the same.

There's two theories on this... First is if you reverse it now you're running on the opposite gear faces which can lead to longer gear life.

The other theory is once you turn a shaft or put pressure on something on one direction it may break easier when you turn it in the opposite direction. Sorta like driveshafts in racecars.

I've swapped drives over the years and it never made anything break and got me an extra year or so out of a gearset.

my $.02

 

[t500hps]

Some people do what he's been told every winter........by swapping the drives so they are now using the gear that had been the reverse gear. No need to open them up just to "reverse" them although I do like to go through my XR's every winter to check them over.

 

[LAKE EFFECT]

On the uppers your not really reversing the gears just loading the gear that was being used for reverse. on the lower you would actually load the gear in the opposite direction.

The easiest way is to just switch the drives, which wont affect the upper gears, but as mentioned you are going to turn the upper, lower and prop shafts in the opposite direction which can cause fatique on those parts.

If the power is modest you probabally wont have an issue, even if your running good HP you might not see a problem. But why take that chance?

I prefer switching only the gears and keeping the shafts spinning in the same direction. You would still be taking a chance with the lower gears, but not on the shafts.

LE

 

[JupiterSunsation]

Power is stock 525's......

 

[Geronimo36]

One last thing to add... in the upper, no matter if you turn the drive left or right the pinion gear is always turning in the same direction and wearing on the same tooth face.

 

[Chris]

Remove the gears and have them cryo treated and isotropic micropolished.

Gears fail way more than they wear. They do this because of surface inperfections and unrelieved internal stresses. The micropolishing removes the scratches and machining marks that are essentially the seeds of cracks. The cryo aligns the granular structure in the metal and relieves the stresses. Your gears will live WAY longer

 

[sy goldberg]

Cyro and isotronic process

Will this work to improve one of my old body parts that is still working but has a lot of time on it ?:26::26:

 

[Chris]

Will this work to improve one of my old body parts that is still working but has a lot of time oin it ?:26::26:

You could strengthen the titanium pieces in an artificial hip...

 

[sy goldberg]

Not hips !

They're fine since I installed zerk fittings in them,I was talking about another old part that still runs well,doesn't listen to me,and even responds to rumors.:biggrinjester::biggrinjester:

 

[J.T.]

I've never had a set of XR gears last 300hrs

 

[Knot 4 Me]

Would not occasional tear-downs to check for correct gear depth, backlash, pre-load, etc. and re-shimming accordingly also help to extend gear life? Forgive me if some of these don't apply to an outdrive.

 

[Chris]

Would not occasional tear-downs to check for correct gear depth, backlash, pre-load, etc. and re-shimming accordingly also help to extend gear life? Forgive me if some of these don't apply to an outdrive.

Not only will it, it's mandatory. That's why drives should be refreshed and resealed at regular intervals- it makes those expensive parts last longer. bevel gears are very sensitive to proper setup. Once some shim and bearing deterioration begins to open those clearances up, the end is near.

 

[OneBadInjun]

Remove the gears and have them cryo treated and isotropic micropolished.

Gears fail way more than they wear. They do this because of surface inperfections and unrelieved internal stresses. The micropolishing removes the scratches and machining marks that are essentially the seeds of cracks. The cryo aligns the granular structure in the metal and relieves the stresses. Your gears will live WAY longer

This is the only way to go for any size drive. That goes for props as well, which saves throwing blades.

 

[Wobble]

I was talking about another old part that still runs well,doesn't listen to me,and even responds to rumors.:biggrinjester::biggrinjester:

Thats is very funny, LOL