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Loud Whirring Noise at the back of 4.3 Liter

G

guyjg

Gold Medal Contributor
I hear a loud noise that sounds like it could be at the rear of the engine. I removed the belt and spun and wriggled each pulley by hand; each was tight and smooth w/o any noise. I put the muffs on and fired up the engine. I used a stethoscope to check each moving part up front; all ok. I checked the OD at various points including the gimbal bearing but no bearing noise. I'm guessing it's the engine coupler? I'm going to try to grease the coupler but it is hard to get to due to boat design. While in the water the other day there seemed to be a vibration through the hull. Engine mounts seemed to be ok...engine was not shaking at idle. Any thoughts or suggestions would be appreciated. Thanks in advance.
 
Ayuh,..... Couplers usually work just fine,.......... til they don't,....

Pull the drive, 'n see what's goin' on,.....

If ya can't reach the coupler's grease zerk, by pullin' the drive you can grease the shaft,.... after ya take a peek at the splines,through the gimbel bearin',...
 
Ok, thanks Bondo I kind of thought I needed to do that. The noise is louder in the back of the engine then at the OD. I tried to lube the gimbal bearing while it was running but it only took one pump. Thanks
 
When greasing a greasable gimbal bearing I normally pump 10-15 pumps as this will force all grease in line thru and you can see it come out the bearing and race.

Unless as suggested, its a permalube bearing...then no grease. Zirk should be removed and a SS screw put in its place.
 
Thanks for all the info. I have MS and it is hard for me to use some tools due to my tremors and arthritis. So I gave in and took it to a reputable shop. I'll know in about a week what the issues are. Getting older is a PITA. I can't do what I could 10 or even 20 years ago.
 
UPDATE: OD needs U-joints, input shaft, gimbal bearing, shift cable, all 3 bellows, water hose, trim & limit pucks (wire insulation frayed), etc.
I could have done all of this myself when I was younger. Oh well, I'll have a good running boat for several years.

Does $3,100.00 sound reasonable?
 
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Ugh sorry. Of course it probably doesn't really need 1/2 of that but ...might as well do it while you're in there sort of thing. I'm trying to plot my course out of I/O world in the coming years into an OB but dang they're pricey.
 
It's reasonable. Of course most all of us here do our own wrenching so we don't pay for labor in the same way. Other than the input shaft, the other bits are what you would normally replace when doing an overhaul of the gimbal housing. I will assume the input shaft has undue wear and the shop is replacing it for that reason.
When you take anything to a repair shop these days, they pretty much have to make it "like new" again or else face possible litigation. That's only one of the reasons that getting things fixed costs so much...overhead is killer.
There may be other odds and ends and if the bonding wire screws are corroded into the housing they'll want to redo those. Those little suckers are a pain.
 
guyjg said:
UPDATE: OD needs U-joints, input shaft, gimbal bearing, shift cable, all 3 bellows, water hose, trim & limit pucks (wire insulation frayed), etc.
I could have done all of this myself when I was younger. Oh well, I'll have a good running boat for several years.

Does $3,100.00 sound reasonable?
Click to expand...

Guy

Did they give you a reason for the U-joints and input shaft needing to be replaced.

Unless the Ujoint assembly has been neglected (lack of greasing for several seasons causing extensive wear to the needles) or (water contamination without being re-greased at a minimum annually to expel the water and needles rusted) I am not sure why they would need to replace these.

Bad u-joints typically cause a knocking/rattling sound but maybe you interpreted it as a "whirring" sound..............

Input shaft, this one would need to be explained.

This part is steel and rarely if ever wears out with the exception of hard use or abuse causing, twisted splines, lack of ever being lubricated possibly causing spines to thin out but I would expect that if the input shaft is bad enough to replace then the engine coupler should also be replaced as that is the weak link of the two parts (input shaft, coupler).


The rest of the parts in list are normal wear and tear items and are commonly replaced for age, wear and tear and preventative maintenance.

As far as price..................I have no comment.

Boots, bellows, hose, cable and trim limit/sender is about a 4-6 hr job depending on several factors at ~ ($100/hr?) Plus parts $$



I could do it for parts $$$ + a couple Benjamin's and a 30 pack of beer...........but I am not a marine business with overhead.
 
They replace them cz if they don't they're afraid that the customer will be back in two weeks making them tear the whole thing apart again for free. Honestly I'm a little surprised they didn't insist on installing a new coupler too.
 
Thanks for all the comments; very helpful. They have me by the neck; just wish I was younger. Yes, it was neglected as I have found going over the entire boat and trailer.

Estimate listed replace "input shaft assy. and U-joints, gimbal bearing, intermediate shift cable, trim pucks, bellows, seals, etc." Labor $1750 parts $1250.

If it lasts me 10 yrs. w/regular service I'll be happy. Thanks again.
 
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Jack: Did they give you a reason for the U-joints and input shaft needing to be replaced?

Got the boat back today. I talked to the mechanic and he stated replacing the entire unit was a matter of repair time vs. taking labor time to replace worn U-joints. Cost was similar when considering new vs. rebuilt. The splines on the coupler were good per him.

He said the main bellows was ruptured at the gimbal allowing water to reach the bearing even though the bellows looked good from the outside. It appeared that the OD was not serviced or lubed regularly and the U-joints were dry.
 
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Yeh. Just paid out $5.5K for new air conditioning here at the Adams Estate of Olde Kensington. I have all the tools and knowledge to install it myself but I paid for someone else to do it. Don't feel like you're spending bad money just because you didn't do the work yourself. Sometimes it's smarter to farm it out and be done than to have a project blown up and strewn all over the shop just cz you didn't want to spend an extra thousand. Now go out there and enjoy it!
 
Mark S.; You'll not like the 4 strokes sold now...slower than a fat pig. Canada was still selling 2 strokes a few years back; not sure now. I would be on the lookout for a good carbureted 150 HP fresh water run 2 stroke; install a new power head if necessary.
 
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