# Yamaha lower unit (AGAIN!)



## DreamWeaver21 (Oct 3, 2007)

Need some advice on what to do. Motor is a 1997 225HP OX66 Yamaha. In September of 06 I was coming in from a trip and the lower unit started thumping like crazy. I drained the oil and it was full of metal. Fair enough, after 9 years and a bunch of hours I can understand a lower unit might wear out. I paid The Maintainance Shop ~2k to install a refurb replacement. Coming into Ft Morgan last weekend from the ADSFR my lower unit started thumping again. Less than 2 years and maybe 200 hours and the unit isbad already?

I'm not flaming TMS becuase I can't say they did anything wrong. 6 or 8 bolts to replace a unit, not a whole lot to mess up. I chang the oil myself and use new washers so I don't think water got in from anything I did. As far as I know the motor shaft is true so I don't think that is causing abnormal wear. I had Accu prop work the prop so I know it is balanced.

Not sure what to do. I will probably go drain the oil today and see what it looks like. I am not excited about the idea of paying thousands more for another lower unit. Any advice?


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## DOUBLE "D" & LV (Oct 2, 2007)

Let us know what the oil looks like. Also, remove the prop and check for fishing line. Out of curiosity, what rpms does your engine idle at out of gear and in gear in the water? Definately need to find out what the cause was so it doesn't happen again. I may have a good used one. I will have to check.


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## Deeplines (Sep 28, 2007)

Don't blame TMS. 

If you go back and look at ALL the old post, once a foot goes out you will replace it about 3-4 times before you decide to buy a new motor.

It lasting2 years issomething unheard off from what I have seen on this fourm. 

I will not call out name but if you want names PM me and I will tell you about folks that REPLACED the lower unit and how many times. 

A friend of mine replace 4, yes FOUR, at close to 2k apiece. He should have just bought a new motor.


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## DOUBLE "D" & LV (Oct 2, 2007)

I don't think he was blaming TMS. Even if he was thinking it, I would see any reason to. It has been 2 years with no problems, and he has changed his own oil. Usually there is an outside source causing the failure in a short time frame.(ie. too high of idle slamming into gear, water on oil, impact, comeing out of the water at high rpms, wrong oil etc).


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## Deeplines (Sep 28, 2007)

> *DOUBLE "D" & LV (7/22/2008)*I don't think he was blaming TMS. Even if he was thinking it, I would see any reason to. It has been 2 years with no problems, and he has changed his own oil. Usually there is an outside source causing the failure in a short time frame.(ie. too high of idle slamming into gear, water on oil, impact, comeing out of the water at high rpms, wrong oil etc).


Your Right. I guess I said it wrong. After 2 years you can't blame who ever fixed it. I was just saying that folks that I know of after replacing their lower unit has ALWAYS had to replace it within 100-150 hours. I was pointing out that once he made it close to 200 he was lucky. 

So for thesconfussion. JUST FROM MY EXPERINECE, When the lower unit goes you might as well by a new motor IF you fish a lot.

Knowing Dream Weaver from his post HE FISHES ALOT. SO two years it must have been a HELLVA rebuild.


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## DreamWeaver21 (Oct 3, 2007)

I didn't get to drain theunit today. I will do it tommorow. Engine out of gear in the water idles around 700-800rpm. In gear it runs around 600rpm. I think the Yam spec is like 760rpm out of gear warmed up in the water so I keep it right in that range. I run a single screw all over the gulf so I am fairly good about keeping up on maintenance Also worth mentioning, when I first got the unit replaced, I noticed a bit of play in the prop. With the motor tilted up I could grab the prop and "lift" it about 1/16th of an inch. Looking at my shop manual, it looks like it might not have been shimmed correctly.


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## Deeplines (Sep 28, 2007)

> *DreamWeaver21 (7/22/2008)*I didn't get to drain theunit today. I will do it tommorow. Engine out of gear in the water idles around 700-800rpm. In gear it runs around 600rpm. I think the Yam spec is like 760rpm out of gear warmed up in the water so I keep it right in that range. I run a single screw all over the gulf so I am fairly good about keeping up on maintenance Also worth mentioning, when I first got the unit replaced, I noticed a bit of play in the prop. With the motor tilted up I could grab the prop and "lift" it about 1/16th of an inch. Looking at my shop manual, it looks like it might not have been shimmed correctly.


If you live on the west side and need help PM me. I have to be at work tomorrow by 3PM.


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## Orion45 (Jun 26, 2008)

Hard to diagnose the problem without inspecting the motor. But here are a fewitemsto steer you towards the solution. 

Answer the following questions:

1. Do you change the lower unit's lubricant at the recommended intervals?

2. Are you using the recommended grade of lubricant?

3. Are you using the correct procedure to refill the lower unit?

If you answered no to one or more of the questions, then you most likely have found the answer(s) to your problem.

If you answered yes to all the above questions, proceed to the next set of questions.

4. What is the appearance of the old lubricant?

a. If milky or if water runs out thelower drain hole- The cause is either a bad seal or bad gasket.I would probably have to guess a bad seal over a bad gasket.Seals can be damaged by a bad shaft(either bent or scarred) or by monofilament line wrapping itself around the propeller shaft. Avery small amount of water will not harm your lower unit since it will eventually drop out of the emulsion and settle at the bottom of your lower unit after your engine is turned off. If you use your engine frequently, this will not happen. Once you run the engine again, the oil and water will again emulsify. That's why I always changed the lubricant at the end of the boating season and halfway thru it. The only gaskets (O-rings) that normally might need frequent replacingare the ones on the drain/fill plugs of the lower unit. Gaskets such as for the water pump housing only need to bechanged when you replace the impeller. Too much water in the lower unit will definitively ruin it.

b.Does the lubricant appear real black (burned)- See questions 1 and 2. Just like in motor oil, the additives break down after a period of use. Also, use the wrong viscosity and you'll ruin the gears.

5. Any metal shavings in the lubricant the first time you changed it afterthe unit was replaced?

Assuming you changed the lubricant after the first 100 hours, and you found metal shavings, the following could have happened:

a. A defective lower unit. I'm assuming the remanufactured lower unit comprised everything between, and including, the upper shaft and propeller shaft.The problem could have been, bad shafts, bad gears, or metal shavings left behind during the remanufacturing process. Hard to determine after two years.

b. Shift linkage is out of adjustment causing gears to grind when shifting. Thiswill cause premature wear. Also, do you gently ease the motor in gear or do you firmly engage it? Hopefully the latter. Easing the motor into gear will cause grinding and premature wear. 

Other than a bad batch of lower unit components (shaft, gears, seals, etc.) from the manufacturer and used in the remanufacturing, I can't think of anything else that could be causing the problem. Search the Internet to see if others have had the same problem and how they solved it. I've taken into consideration your statementthat the propeller has been properly balanced. 

The only other recommendation I have is that you take theengine to a qualified Yamaha mechanic for a diagnostic. I assume the remanufactured lower unit is out of warranty by now. If not, take it back to the remanufacturer.

Hope this helped. Good Luck.


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## Deeplines (Sep 28, 2007)

I DON'T THINK DreamWeaver21 is no ROOKIE. He has placed in MANY a Tournys over the last 4 yrs this PFF has been aboard. He has WON 1st place in one of Tommy's Tournys. 

The man is so GOOD, I remember him going out about 2-3 yrs ago in the adsfr and timed it so good that he went the max his boat would allow and came in in time to call SEA TOW to have him pull him to the docks so he could weigh the winning fish. 

NOW, if that is not experience and you don't think the man knows how to change his lower unit oil then WELL................

JUST A NOTE:

I have never meet the man. Only from what I read on the Fourm.


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## DOUBLE "D" & LV (Oct 2, 2007)

The prop shaft will have about a 1/16" endplay except on counter rotation models. Let us know what you find.


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## Orion45 (Jun 26, 2008)

*Deeplines*,

I did not imply DreamWeaver21 was a rookie or that he did not know how to change his own oil. I neither knowthegentlemannor do I have any knowledge of his seamanship or fishing expertise. I just joined the PFF and was answering a post. There were no replies when I first read DreamWeaver21's post. I started composing my reply but got sidetracked. By the time I finished and posted it, there were five other replies posted. Had I known that, I would have greatly abbreviated mine.

Also, I'm sure you have heard of a "Logic Tree" approach to problem solving. If not, I suggest you research it on the Internet.It is basically a flow diagram with yes/no branches which eventually lead you to the correct solution. Most technical manuals have them.

Next time, rather thanposting negative comments about someone else's reply. I suggest you offer your own solution - if you have one.

Have a nice day!


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## Deeplines (Sep 28, 2007)

Nothing ment by it ORION45. We have another ORION on here and FOR THE GOD OF ME I couldn't figure out why he was hitting on him about how to do something. 

My bad.:reallycrying


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## Orion45 (Jun 26, 2008)

Apology accepted. Thanks.


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## DreamWeaver21 (Oct 3, 2007)

Thanks for the replies so far. Wasn't me getting towed by SeaTow though, I have only used their services once when my steering went out and that was out of Pensacola. Bad part about that was I had a whole bunch of people waiting to have a fish fry and had a good mess of fish on board too but I had to call them and tell them to go to the store for burgers and fire up the grill because we weren't going to be in for a while...:angel:doh

Back to the engine issue...Gavin from TMS saw this thread and called me todayand said bring it over so we can look at it. I took it over this morning and we drained the oil. No water in the oil. None. It was black / burnt and though and there was metal flake in it. Not as much metal as the last time I had one thumping but still too much. He is going to call the company that did the rebuild and see if they want to take a look at it. It is obviously out of warrantee so I can't expect anything but who knows, it doesn't hurt to ask.

To answer the other questions:

-Oil is changed at regular intervals. After getting the reman unit I changed it at 20 hours and then at 100. It was close to time to change again. There was some flake at 20 but that is normal.

-I use the correct grade oil.

-I don't leave the shift lever in the "grind zone". Now that I think about it though, I did notice the throttle was a bit firmer to move into gear on the last trip. I figured it was corrosion on the wire but maybe I figured wrong.

Thanks for the offer Deeplines.


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## Rammer Jammer (Oct 1, 2007)

Weaver - go ahead and break down and buy that 23 cape with twin HPDI's and be done with it; you know you're looking for a reason. oke

That 225 SWS has got to have like a billion hours on it by now. That's one hell of a motor!


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## wrightackle (Oct 29, 2007)

Run, don't walk away from any boat that has hpdi's hanging on it. With the way you use a boat you'll be blowing powerheads right and left. They aren't near the motor you have now. If you repower go the four stroke route. Sure wish you luck with your motor.


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## Worn Out (May 10, 2008)

Amen to the run from 250hpdi. I went through 6 (in 350 hrs) before they allowed me to switch to a 225 4 stroke.Ruined a few vacations, and a few 'trips"...


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