Grinding Sound from V Drive

M

mawyatt

New Member
Dec 13, 2007
1,001
Clearwater, Fl
Boat Info
2008 Sundancer 38DA
Engines
8.1L Mercruisers
One V drive is making a nasty grinding sound in both forward and reverse idle (and higher rpm) on our 2008 38DA. This is something I will probably not want to tackle myself. Can the V drive transmission be pulled without having the boat hauled?

Thanks,

Mike
 
change your spark plugs, that's gonna solve that grinding noise. Ask me how I know...
 
The short version is that the engine is running rough and *could* be a cause for the grinding in the transmission . I'll let Kreole kid expand.

As for doing transmission in the water while it could be done I'm not sure you would want it done that way. If it's something major the shaft is likely coming out for inspection so the boat would need to be pulled any way. When I blew a transmission last year they where able to get it out without pulling the engine. You 38 ER is bigger than mine but the access hatch opening is not square so I'm not sure if they would be able to tilt the engine and remove the transmission the way they did mine.




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A friend with a 310DA lost a valve and he thought his tranny was shot. Had the heads done and fixed the fuel injetors (that was what ate the valve) and he is all set.
 
No, you cannot pull the transmission with the boat in the water because on v-drives, the shaft passes thru the lower case on the transmission. The shaft has to be un-coupled and moved back to where the forward taper is almost at the shaft seal. All things are possible if you throw enough money at it, but getting the prop removed and shaft pulled back by a diver will cost a lot more than a simple haul out......doing this in the water just isn't practical.

I'm not discounting a gas engine causing some shake in the drive line, but your description is exactly what one would experience when the intermediate shaft or its bearings fail.
 
fwebster said:
No, you cannot pull the transmission with the boat in the water because on v-drives, the shaft passes thru the lower case on the transmission. The shaft has to be un-coupled and moved back to where the forward taper is almost at the shaft seal. All things are possible if you throw enough money at it, but getting the prop removed and shaft pulled back by a diver will cost a lot more than a simple haul out......doing this in the water just isn't practical.

I'm not discounting a gas engine causing some shake in the drive line, but your description is exactly what one would experience when the intermediate shaft or its bearings fail.
Click to expand...

Frank said it much better than I.

As I said, I experienced this last September and unfortunately the bearings failed grenading my transmission.

Here's that fun thread.
http://clubsearay.com/showthread.php?t=69229





Sent from my iPhone using Tapatalk
 
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Thanks for the notes. I did run into a sand bar last year that had moved right on my way point through Hurricane Pass here is Clearwater. Both engines and generator sucked up sand. I dropped anchor and cleaned the strainers out but the port engine was overheating so I returned to dock on one engine. After removing the raw water pumps and flushing the engines they were OK but I had a vibration on the port engine. I took the boat up to Pelican Marine in Tarpon Springs, we ran at low speed. They found the port prop was out of alignment. We had the bottom paint done and the prop aligned by Pelican (did a great job too).

We haven't taken the boat out since returning last year (family issues have prevented us from using the boat). I do start the engines and engage the transmissions periodically at the dock and this is when I noticed the grinding sound from the transmission.

The port engine is running very rough also, not sure why. I changed the plugs less than 75 engine hours ago, but could be due to bad gas, but the starboard engine runs fine. I just may need to replace the plugs again and/or get new IAC valves (they are original).

Does the V-Drive sound like it might qualify for insurance coverage? We have never claimed anything on our policy, its with BoatUS.

Thanks for all the help,

Mike
 
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mawyatt said:
Thanks for the notes. I did run into a sand bar last year that had moved right on my way point through Hurricane Pass here is Clearwater. Both engines and generator sucked up sand. I dropped anchor and cleaned the strainers out but the port engine was overheating so I returned to dock on one engine. After removing the raw water pumps and flushing the engines they were OK but I had a vibration on the port engine. I took the boat up to Pelican Marine in Tarpon Springs, we ran at low speed. They found the port prop was out of alignment. We had the bottom paint done and the prop aligned by Pelican (did a great job too).

We haven't taken the boat out since returning last year (family issues have prevented us from using the boat). I do start the engines and engage the transmissions periodically at the dock and this is when I noticed the grinding sound from the transmission.

The port engine is running very rough also, not sure why. I changed the plugs less than 75 engine hours ago, but could be due to bad gas, but the starboard engine runs fine. I just may need to replace the plugs again and/or get new IAC valves (they are original).

Does the V-Drive sound like it might qualify for insurance coverage? We have never claimed anything on our policy, its with BoatUS.

Thanks for all the help,

Mike
Click to expand...

Mike start with your spark plugs and see what happens, I had some damage done on my maiden voyage home back in 2009. I didn't know of the damage until a year later, called my insurance company and they where "Johnny on the spot".
 
A mechanical failure is usually not a covered loss, but if you can connect the transmission failure to your grounding, then it most likely would be covered.

It is worth pursuing since the transmission replacement is $6500-$7500 plus the haul out, plus several days in the boat yard, plus roughly 15 man hours of a mechanics time. I personally would never rebuild a transmission that had failed bearings, shafts and gears. They have a fluid pump and the lube oil also acts as a hydraulic oil to engage the clutches. If failed parts have generated a load of metallic shavings inside the transmission, then they have been pumped throughout the system and will be very difficult if not impossible to clean up. Since the labor, haulout, and lay days are a fair % of the replacement cost, you don't want a do-over on this one. I would (and I did a few years ago) buy a new transmission with a warranty rather than take a chance on a rebuild.

After verifying that the engines are running properly, the next thing I would do is to run the engines in neutral to circulate the transmission fluid, then change it, save the old fluid, and pass a magnet thru it to see if you get many ferrous particles which would indicate bearing, bearing race, gear, or shaft damage. You could also strain the fluid thru a white cloth like an old T-shirt.


One other point on removing the transmission: you must have enough room to move the transmission toward the front of the boat several inches in order to disengage the flywheel coupler from the input shaft on the transmission. If you can't, then you will probably have to have both the engine and transmission lifted or removed to get the needed clearance.
 
While you're addressing the engine side, I would take transmission oil sample and send them to the lab to have full and detailed report. Do both sides. Make sure to do it on warm tranies.
 
While a fluid analysis is never a bad thing, sometimes it is just over analyzing a problem. If you have a major parts failure in a transmission, it doesn't take a fluid sample to see it in the fluid.


Both have 875 hours total time on them, this is what was caught when the fluid was filtered at 125 hours on the last fluid change:

trans2.jpg


It is pretty obvious that the port gear has a part failure going on:

trans3.jpg
 
Wow, you're not kidding about the obvious picture there, Frank.

I was just following more optimistic theory where OP is not sure if it's trainy issue, and hopefully it's engine tuning related one.

Going with your theory, I think that while extracting oil with a hand pump for an oil analyses, after letting the oil settle in the test bottle, it should be easy to spot anything obvious like what we see in your picture. It's a lot easier to see thru clear color if Straight 30 oil type (diesel boats application), but if I recall the ATF type oil (mostly gas boats applications) I used on my 320 trainies, was still "clear enough" to see any metal deposits.

It basically boils down to the need for an oil extract for at least visual inspection. If nothing can be seen by naked eye, I'd send it to the lab.
 
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Alex,

The sample in the photos were taken from Hurth/ZF 80 series gears using ATF powered by Caterpillar diesels. I know because they are mine. I will also tell you that I first discovered a "pending failure" 3 years before we actually replaced the bad transmission. I found the first indication of the problem by looking at the wash solvent from the filter screen in the port transmission and seeing metal particles. I confirmed the bad news with a magnet. Gears, shafts and bearings are made of steel and are magnetic; clutches from brass, copper and carbon residue and the gear case is aluminum which are non-ferrous and don't stick to a magnet. I had a failed intermediate shaft and bearing.

I will also tell you that being able to spot an impending problem is the reason I change my transmission fluid every year. As it turned out, we were able to shop sources for the new transmission and schedule its replacement on our time table and not as an emergency.
 
Frank,

Your story is a classic example on RIO for DIY people, who don't mind rolling up their sleeves and get their hands dirty, who believe in preventive maintenance and follow proper do diligence and monitoring steps. You took the pro-active approach, which allowed you to stay ahead of the problem. After you've collected all the facts, you had plan on the best course of action to address the problem. And the key part is, when it fits nicely in your schedule "...and not as an emergency".

Perfect plan and execution :thumbsup:

Just like yours, my transmission gets an oil change at the same time with the mains (annually or based on the required hours, whatever comes first). In addition to that, I do all 5 oil samples before the oil gets changed. I figure that's the least I can do to be in pro-active mode.

Going back to the OP, it sounds like (and it's just my assumption based on the info we have so far), that OP doesn't have a good record of oil samples and is forced to be in "reaction mode". So, I would follow the analyses steps provided in earlier posts. Trainy issues is a complex one, there are tons of variables and it's important to collect as much data as possible in order to draw a valid conclusion. I'm very curious on findings and resolution steps in this case.
 
Diagnosing without tools and only a written description is at best a WAG. Determining if the transmission has internal issues is pretty easy to determine with a stethescope........sounds like a gallon can full of marbles and the sound gets fainter as you move away from the gear. With an engine miss, the sound will be louder at the bell housing and more faint as you move toward the shaft coupler.
 
I hope to be able to get to the boat this weekend (other issues have kept me busy) and follow the advise given, thanks guys!! BTW I did make contact with my insurance (BoatUS), and they were extremely helpful as well.

Cheers,

Mike
 
Kreole Kid said:
change your spark plugs, that's gonna solve that grinding noise. Ask me how I know...
Click to expand...

You were right!!! I finally got to the boat today and removed a couple plugs from the port engine, they looked pretty bad. I looked at a stbd engine plug and it looked much better. Installed new plugs in the port engine and the "roughness" is gone and so is the grinding sound when in gear!! Amazing, I would never have thought plugs would make the engine/tranny sound like that!!

Probably try and take the boat out tomorrow if I can. I could only run at the dock because it was getting late and I had to leave.

Thanks to everyone especially you Bruce.

Mike
 
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