XR Gear Failure
 

It's been a while since I posted last but have some Questions for the masses.

I have a 2001 Powerquest 380 Avenger with 500efi's running XR drives on the ITS system. The engines and drives are not the original and were installed last year. I took the boat in for a 100 hour service to have the dealer look over everything before the warranty ran out. The engines/drives have about 60 hours on them. I have changed the engine oil and drive oil 3 times since installed and run Redline Heavy shockproof gear oil. The boat is run at 4,000rpm 60% of the time, 3,500 rpm 35% of the time and 5,000 5%. The boat rarely leaves the water, maybe had a dozen times the drives have come out of the water and I have never hit the rev limiters.

The drives were pulled and there is water in both drives:eek: . The mechanic told me that the merc gear lube will mix with the water to help prevent excessive wear in a case like this and that the Redline does not allow the water to mix and will create pockets of water and therefore no lubrication. Both drives have to be reseeled, both need new gears and one needs a new gimbel bairing. I dodged a bullet and merc is covering the repairs (may be worth paying mercs prices if they back their products this well).

I have two questions:

1. Why would both drives have leaking seals with so few hours? Is there something in my driving habits that could have caused the failure?

2. Should I go back to Merc gear lube? Is the Redline more for the racer who tears down often and changes fluid everytime the boat is run?

Thanks, I know someone here will have some insight as to what happened.

My opinion-stick with the merc green. They manufactured the drive and custom make the oil specifically for their drive. The oil has the properties that they feel are critical for the drive to live. I once put the question to a engineer who worked on developing the bravo drive. He said that they had tested other products. Some products had properties that had definite advantages over the merc product. The problem is that many of the products had disadvantages over the merc oil. But none of the other oils had the optimal combination of all the properties.

I have run lots of hours (100's) with Redline and Merc gear lubes and can't really tell the difference. I have also run over 800 horsepower on these Bravo's without failure; but I have never had water in my gear lube. It seems to me that no matter what gear lube you run until you keep the water out there would be a risk of failure!

I was told theres a update seal on the xr drive. Not sure if this is why the water is geting into the drive. Do you have to keep adding to the drive oil? I think my xr drive is leeking drive oil, there only 8 hours on it.

Quest for speed


What year is the ITS and Engine combo. Also how fast is the boat with that setup (curious) Were you getting any drive whine?

I have the same setup (boat and engines) with no apparent problems in 70 hours but there is a faint whine coming from the starboard drive when compared with the port. Not sure if it is a function of drive direction (spinning opposite). I have been running merc green all along. Like you I have changed the drive oil three times and my driving habits are very close to yours.

P.S. was that boat originally powered with a volvo DPX?

Migpilot, the system is an 02 and I have no whine from either drive. I did have to add drive fluid to port side the last run before service but did not see any water in the resevoir.

I am running around 81 for top speed but the boat is not yet propped properly. I have run three different sets of props and have not gotten above what I want yet. I am going to go to one of the local prop shops and see if they will let me demo a number of props to find the right set-up. My current set cruise great so I don't want to play with them but they only hit just shy of 5,000 rpm.

Quest,

My boat turned out to have a slightly higher top speed running at 5000 than it does now with lab finished 33'S pitched to 31 by merc at 5300. 80 is the best I have seen at 700 feet msl and cold lake michigan conditions

Just drained my drives last night with barely a hint of flakes and clean lube at 80 hours total time. Is it possible that your drives didn't get serviced properly. I am sure our drives were manufactured within week of each other.

Thanks. That's why I won't touch the current props I have, don't want to mess up a good thing.


Anyone else have any ideas why water would get into both drives and wrench both sets of gears without tearing up the bearings?

Propshaft seals can pick up some fishing line and let water in. The upgrade seal that was talked about is a new seal retainer for the input shaft. It wont let the seal be forced out of the retainer because it has a lip. Usually the resevoir bottle will need filling if that seal has been pushed forward and leaking.

One thing to do is have the drives presure tested after assembly, some do positive and negative psi to catch a problem..


Good luck

Dick

The thrust faces of the gears obviously are at the greatest risk of failure with a lube breakdown with the bearing be able to withstand these conditions longer. I am thinking that your drives may not have been serviced properly allowing for some air to be trapped in the drive. When the drives cooled it may have literally sucked water into the drives. The procedure for refilling is fairly specific about reinstalling the vent plug then continuing to pressure feed the drive to fill the drive monitor resovoirs. This allows the dribble valve to have the proper pressure on each side of it to let the lube flow both way to allow for heat expansion and contraction at the same time making sure there is no air in your drive. What other commonality besides a possible manufacturing defect do the drives have in common.

Same set up on the OSO Gladiator. At 120 hours the gears were flipped. At 240 hours the gears were replaced even though they still had more time. They were replaced as preventive maintenance for the World Races.

AS WE HAVE SAID A MILLION TIMES ON THIS SITE, USE THE MERCURY. THE OTHER OILS HAVE PROVEN NOT TO LUBRICATE AS WELL.

Bearings are more forgiving than gears as far as failure from water. Most likely a previous service was not done properly and that is why the water is in their. Of course the fishing line theory is a good one but highly unlikely to occur in both drives at once.

Drain Plug gaskets were probably not replaced.

water & any kind of oil does not mix!!!if your drives have water in them they need resealed.i would get a new mechanic he doesn't know what he is talking about

At 100 hours my xr sport master blew the top cap off coming home from the KW Poker run. So now I'm buying new gear sets along with switching port side drive to starboard side.. I wish someone would build a better drive!

I think a better drive is out there - the Volvo DuoProp. I have been super impressed with every one that I have driven, and they seem to be pretty bulletproof. If someone has something to the contrary please let me know.
I have only owned bravos because they are the most popular and seem to have better resale value. I hear about problems with every bravo, or bravo derived drive. Even with relatively calm power. On the other hand, I have almost 500 hours on my drives without a problem, and I know others that are the same. It seems to be feast or famine.

Steve

baja27, do you have ITS? If not, the drives are notorious for those bolts coming loose. Don't ask me why but have seen it over and over again on non ITS set-up.

Most good drive mechanics will tell you that 90% of failures come from bad maintenance and driver error. On rare occassions you will see certain boats with funky set-ups that eat drives but very few and far between.

OffShore it is not a ITS set up, also the bolts did come loose I was able to retrieve 2 of them , but in the process it destroyed the upper big time.

Troutly, I did not notice any water in the drives when I changed the fluid. I also did not have a problem with the oil foaming. I did have to top off the port drive resvoir on my last run but it was not down very much.

I guess I did not get the drain plugs sealed propperly but I have no idea how I could do that. IS it possible that something was not installed correctly?

We broke a drive this past weekend on our Top Gun (T/S, 500 EFI's, XR's) and the Top Cap was destroyed.

The boat is at Teague right now getting fixed, and we are putting Teague billet top caps on.

According to Teague the stock top cap is a weak link on the XR. I was suprised how thin they were judging by what was left.

I had an XR on my last boat running mover 800 hp, but had the billet top cap and never had a problem.

I lost an XZ drive this year with 140 hours on it.

The top cap broke internally and melted down and locked up the drive.

We service our equipment to death and had switched to Synergyn Synthetic just last winter thinking it would be better.

Mercury replaced the entire drive free of charge even though it was three weeks out of warranty.

In the process they made a believer out of me in their products. I have changed back to their High Performance Gear Oil.

Now I want billet top caps, but I will have to change my Steering brackets to had them due to the fact they are taller than stock.

Sorry about you problems, but another good point is the little o-ring type gaskets. I buy them a dozen at a time and replace both the drain and side vent gaskets everytime I take a plug out.

Good luck

Doc

My starboard side broke the top cap this year also. I'm going to look into the billet top caps too. Anybody have any info on who has the best ones?

Quest

Do your drives have drive showers? If they run too hot they can suck water in through the seals when cooling down after hard runs.

Quiet Storm, I am running the Simrek drive showers and have had no chalking on the drives at all. I am getting nervous about changing the drive oil myself now. I fill the oil back up through the drain plug all the way to the reservoir instead of pouring fluid in the resevoir after the fluid has reached the side plug. I just hate to have to take it to the dealer every 25 hours (pain in the a$$).

USE THE MERC OIL
 

I USE MERC OIL BOTH IN MY AO AND MY 32 SKATER. 970 HP ON BRAVO 1.36 XZ AND 1230 HP ON 1.24 #5'S I SHOW THEM NO MERCY. 125HRS ON MY XZ'S AND I FLIPPED THE GEARS WITH NO EXCESSIVE WEAR. :crazy:

About the duoprop, I know of one that is on the bottom of lake michigan. And in fact quest's boat may have been the donator before it was remotored and redrived at great expense. But I have no personal experience just responding to your question.

I have experienced the drive reservoir's filling up with fluid above 3000 rpm. I run Merc fluid. One time it was caused by a bad reservoir cap and the other time by a leaking drain plug seal. I regularly check the reservoir's to see if they are filling up at wot. If a Bravo drive is not fully sealed the drive fluid will raise and even overflow out of the reservoir.
Dan