Smitty, have you been running these gears and if so, what were the results? I just bought a set and they look very nice right out of the box, smoother finish than Merc gears. I'm going to install them in my spare drive next week. Hopefully, it will be a while before I'll be testing....

Kurt

I have not ran them yet. Bought the whole lower kit with bearings, bored out the gear to fit the Max worx xr shaft , sent them out to be cryoed and isoed. They are sitting in a box still. Finally broke my upper gear set at end of season last year after 100's of hpurs with big power, putting new gears in that and going thru lower in next few days. IF my old gears need repa=lacing they are going in behind 1000hp and ft lbs of tq, will post what happens.

Thanks for the reply. FWIW, I'm done with the Cryo/ISO treatments. I've seen zero results from this process. My last three failures were Cryo/ISO'd and they were still badly pitted. Looking forward to seeing how the aftermarket gears hold up.

I wish SEI made XR upper gears, just to able to get something besides Merc gears that as so expensive.

They SEI realize the failures in the uppers so IMO and for what they want their units to sell for (cheap pricing) I do not think they want to keep warranty all the Bravo upper failures plus you will have boat owners putting some big power thru them increasing the failure rate on the SEI product.

Everytime I asked SEI in PERSON when is the Bravo upper coming - their comment was always Mercruiser patient still current so we can not bring it to market yet. They have been telling me this for the past 5 years. Just saying..

Just want to add their complete Alpha unit is not bullet proof no more or no less that the OEM Mercruiser. Actually with SEI I have seen more small issues right out of the box than I care to. Brand new drives right out of the box not holding pressure, impeller failures, paint peeling badly, bad gaskets - upper getting extremely hot and extremely noisy and so on. But for the money and warranty why not use them I would to.

I just gernaded an SEI alpha drive. Bought it last year. I did the break in process and changed fluid this spring. Third time out with the boat and it ate the upper gears.

Like I said these drives are not as good as everyone thinks. Keep in mind I see at least 1 a week. But again the price is right and the warranty is really good. FWIW.

I was able to double the life of my lower gears using the process at 1000 hp/ft lbs of tq, how many hours are you getting before they pit and what oil? I was testing with royal purple and found its the worst synthetic out there, amsoil sever gear and bravo shop mix have both worked great for me.

Typically, about 35 hrs before seeing more debris on the magnets than I'm comfortable with. I then swap drives side to side and get another 30-35 hrs before they are shedding again. Tried many oils, getting the best results from Mobil 1 Delvac. 75-90, NEO Synthetic did nothing for gear life in my application. -All testing has been done with 34 Hering 5 blades. Now running labbed 37 Bravo 4 blades. We'll see if drive life is extended with the 4 blades..

As mentioned many times before, I feel the Merc gears are very inconsistent. Most sets are garbage and occasionally you get a set that sets up well (backlash consistent within 360 degree rotation) breaks in well and lasts. One of my drives presently has about 140 hrs on it since rebuild (also Cryo/ISO lower gears, upper pinion Cryo/ISO too) with zero debris on magnets..

The flaking is due to lack of hardness depth. And some gear oils cannot live with the load. Mobil Delvac is the best choice. The fix is to get away from the net forged gears. Not available yet. :)