250 pro xs lower unit seized

[Newarkbass1]

A friend of mine has a 2008 pro xs250 on his ranger . Recently the lower unit locked up he took it to a merc dealer and the merc. warranty rep. said his motor is raised to high and caused harmonics to loosen the ring behind the prop and cause the seal to leak and the LU to fill with water.By the way this was all done over the phone, not in person.They also said this a common problem and he was lucky they were covering it. The motor is still at factory height and he has 30psi at wot. We were just wondering if this is a possibility considering some bassboat hulls run their motors extremely high.

[howieranger]

If his boat is also a 2008 Ranger normal prop height for the Rangers rated for a 250 would be between 3.37" and 3.25" below the pad. Without more information this seems a bit bogus. What model does he have and what is prop-shaft to pad height and does he have a jackplate??

[Newarkbass1]

It has a jack plate that has never been touched it is all factory set from ranger and the boat is a 2008 we just want to know about the harmonics causing this ring to come loose

[EuropeanAM]

Inspection of hub components and propshaft would be necessary to make this determination.

Mercury relies on the DEALER'S inspection in 99% of cases... since most are Factory Trained.

I doubt, however, that this engine was mounted too high, based on the noted water pressure.

[jbuck]

I have a 2008 Ranger Z21 w 250 pro xs and mine just did the same thing. It didn't seize up becaue I noticed oil on my carport, but when the drained the lower unit it was full of water. Mercury replaced lower unit, just picked up boat yesterday. My seal behind the prop was half gone. Might just be a Merc problem? Had to wait 10 days for a black LU cause they were on back order.

[Dennis H]

Know the feeling...1st all, my motor is on a jackplate also but it is still at factury zero which places the prop, etc. below the hull...I also noticed oil on driveway took boat to shop, they replaced lower seal which was cut/torn, whatever...took it back to lake next week, parked again noticed oil on driveway, took back to dealer where they said seal was again cut/torn. They replaced seal very carefully again, I watched and again I left to the lake, and yes! the unit let go while running down lake this time...took boat to dealer and left it. They told me they ordered a new lower unit but it was on back order. Obviously there is a problem (no clue what could be causing the lower seal to let go) and in this case the repair shop didn't know of a problem (or did they???). I'm glad to read this post because now I have some real questions for my repair shop. Thanks to the guys who post on this board letting us know that I'm not alone in having this problem. I'll post whatever comes out of my perdicament.

[jbh3]

The carrier bearing seal is one known issue for these engine's cases. My 2007 225 Pro XS L/U has been resealed multiple times. I'm either on the 4th or 5th reseal. The last time, at my request, my shop contacted Merc tech support seeking a replacement L/U. Merc instructed them to use some new/mysterious, "special technique" to install this seal. Said if it leaked again, they would replace. Folks, we need to watch these units, CLOSELY.

[jignpig_72]

Prop seal went out last year, lower unit went out this year. 2008 pro xs 250. Think there are a bunch of bad, cheap seals. Prob similiar to the coil deal. JMO.

[2100greenmonster]

Not to hijack, but why are lower units on back order every where. Have two friends waiting on a back ordered lower unit. One in on a 225 Opti, other is a 250 Proxs. Seems odd that they aren't readily available. Is Merc having some lower unit issues?

[EuropeanAM]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by 2100greenmonster &raquo;</td></tr><tr><td class="quote">Not to hijack, but why are lower units on back order every where. Have two friends waiting on a back ordered lower unit. One in on a 225 Opti, other is a 250 Proxs. Seems odd that they aren't readily available. Is Merc having some lower unit issues?</td></tr></table>

Increased engine demands for new engine production (resulting in shortages for some engine components).

Think about recent events in the Japan area... where many other engine brands are produced, and then add to that the seasonal increases in parts demand.

[2100greenmonster]

that's a valid point

[TRCM]

What lower unit are these ? Wondering if I need to worry or not.

[EuropeanAM]

Torquemaster 1.75 ratio, I believe.

[JAZII]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by 2100greenmonster &raquo;</td></tr><tr><td class="quote">Not to hijack, but why are lower units on back order every where. Have two friends waiting on a back ordered lower unit. One in on a 225 Opti, other is a 250 Proxs. Seems odd that they aren't readily available. Is Merc having some lower unit issues?</td></tr></table>

Maybe checking for casting flaws.
Seems to be allot of Merc lowers letting loose at or just below the mounting bolts.
I have seen at least one at every 75 boat or more tournament last year and this year, with my own eyes. NO IMPACT DAMAGE SEEN.

JAZII

[scottcr]

If you over fill the gearcase with to much lube you will blow the seals... This gearcase does not require you to fill to the overflow and put the nut back in. It takes less oil than that to fill. I learned the hard way. Mine did not leak on floor but came out going down lake. The gearcase will take on water.

[JAZII]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by scottcr &raquo;</td></tr><tr><td class="quote">If you over fill the gearcase with to much lube you will blow the seals... This gearcase does not require you to fill to the overflow and put the nut back in. It takes less oil than that to fill. I learned the hard way. Mine did not leak on floor but came out going down lake. The gearcase will take on water.</td></tr></table>

Not the issue on hand.

Actual gearcase fracktures just below the cavitaion plate, sometimes leaving part of the casting attached by the mounting studs.

JAZII

[EuropeanAM]

Would be interesting to know what torque value the mounting nuts (and rear bolt) were torqued to.... and "when" they were last torqued.

Should be part of everyone's annual maintenance schedule.... done right along with the water pump.