unusual noise

[John Hink]

Hello, Forum;<br />I checked the last 100 days for this subject and didn't find it.<br />My boat is a 1972 Starcraft fishing boat W/181 cid engine w/mercruiser1 outdrive.<br />Very recently during a trolling episode there was a tremendous squealing/grinding noise erupted from what sounded like the outdrive. I thought I had picked up some wire line with the prop. After stopping the engine I looked at the prop and it was clear. I checked all the rotating items and the oil level in the crankcase to be assured nothing was frozen.I restarted the engine and the squeal was still there,but necessity of the situation determined that I try to get back in to dock,so when I moved the control handle forward, the outdrive did not engage. I tried the reverse gear and there was no response there either.<br />I removed the outdrive and took it to a Marina for inspection. After it was disassembled, there was nothing found that would cause such a noise.I did not take the boat to the marina so he could not say what else there might have been happening that would cause this.<br />We talked about engine couplers, shaft carrier bearing, rotating parts,etc;<br />I am just before pulling the engine for a look at the flywheel and coupler.<br />I did find two pieces of wire about three inches long that had been ground on by something. I ask about them and he had no knowledge of such a thing as locking wire inside the flywheel housing. I started the engine with the outdrive removed and the noise was absent. <br />I am reluctant to pull the engine without having the alignment tool to reassemble the outdrive to the engine. I could use the expertise of your experience and wisdom . It might be that I may not need to go that extra mile in the cold.<br />I know that if you can help, then you will, and I do appreciate that help very much.<br />John Hink

 

[Haut Medoc]

Re: unusual noise

Gimbal bearing? >IE Does it spin freely? Can you see where the two wires start?....If it doesn't make the noise with the drive off, well....I could be going out on a limb here.....But it is a problem from the gimbal bearing to the outside....& No need to pull the engine, yet....How do the splines on the drive shaft look? Did you overheat?....JK

 

[Bondo]

Re: unusual noise

Ayuh,...... What JK says,........<br /><br />It Sounds like Either, or Both the Coupler,+, or the Gimbel Bearing,........<br /><br />The Gimbel Bearing is Inspectable from Outside,.... Just reach in thru the Gimbel Housing,+ Spin the Gimbel Bearing,.... <br />Does it Feel Smooth,.??... Is it Well Greased,.??...<br /><br />Now,.... Look Through the Gimbel Bearing,... You should be able to get a glimpse of the Coupler Splines,... <br />What do they Look Like,..???... How about the Splines on the Outdrive's Input Shaft,..???.....<br /><br />After the inspection,... Then you'll need to make the decision wether to Pull the motor or not,........<br />It's Not that Big of a Deal........<br />Especially if You've done All the work besides the Alignment,...<br />It shouldn't cost very much to have your Marina do an Alignment......<br /><br />As for the Wires,.......Are they plastic coated Copper wires, or Steel wire, Or Braided wires,.????

 

[John Hink]

Re: unusual noise

My thanks to both of you for the fast return information.<br />The gimbel bearing is free turning as to say, it does not spin like a dry ball bearing will spin, but when I place two fingers in the pilot hole and turn the inner race, it feels good, smooth and firm.The outdrive shaft splines are as good as they get.I cannot see through the gimbel bearing to make a comment on the coupler , however if the shaft is an indicator of the condition, then it must be alright in the splined area. There is a special tool required to remove the gimbel bearing and snap ring that I don't own.The marina refuses to loan it and I hesitate to pay the shop rate when there is no positive knowledge that it is required.<br />The two pieces of wire are steel and appeared to have become heated enough to turn blue color. Some type of plastic insulation is attached.<br />The mech/owner at the marina has no knowledge about the what they might be a part of,because normally there is no wire like it inside the area it was in.<br />What is there that would prevent the outdrive from going in gear? The shifting mechanism was all moving as it should, but there was no response at the prop.<br />Can the coupler simply strip out during a slow troll operation of perhaps 3 knots? There was no prior warning that I would associate with this.<br />Thanks again for your input,all. I will try to see the coupler splines and report back. In the meantime, if you think of anything else let me know? John Hink

 

[John Hink]

Re: unusual noise

I missed an important question; was it overheated?<br />The answer ; not since I have owned the boat. <br />but then it has not had a lot of running time with me, either.Perhaps 40-50 hours combined. It's history would include service in the US Army recreation program, so there is not much telling what kind of hardship was pressed onto it. It was in very bad shape when I took it over. So I would have to say, the maintenance was sadly neglected on the I/O as well as the hull.<br />Thank again. John Hink

 

[Bt Doctur]

Re: unusual noise

exactly where were these pieses of wire?If inside the boot itself,it might be the remains of the spring that holds the boot shape.your gimbal is a non-greaseable type unlike the later units.the snap ring is easily removed by adapting longer handles to a standard set of snap ring pliers.if the drive and shift cable check out for proper operation ,then replace the gimbal with the later one.remove your old one with any shims and install the later gimbal with the tolerance ring.

 

[Bondo]

Re: unusual noise

I Really Don't think your problem is the Gimbel Bearing........It Could cause a Rumble,.. But, Not loss of Thrust.......<br /><br />The Wires aren't Ringing any Bells Yet,..... Exactly Where were they Found,..????...<br />They Could be some Continuity Wires from Somewhere......<br />Or even Old Bilge Debris.......<br /><br />The Question about Overheating is about When the incident was Happening,..???... <br />With a Blown Coupler,... Nothing in the Outdrive is Turning,...<br />No Shifting,... No Thrust,..... No Waterpump Turning,...... OverHeat......<br /><br />I think This IS your Problem,.......<br /><br />BTW,......<br /><br />Trolling is Harder on the coupler than WOT........<br />At WOT the coupler has taken the Energy,+ is Constantly Loaded...............<br />Trolling,..... The Coupler is Constantly Loaded,+ Unloaded,.. Over,+ Over,.....<br />As the Motor pushs the Boat,... Then the Boat pushs the Motor..........<br />It'll Wear the splines to Dust in no time if it wasn't Greased properly,+ Timely................

 

[John Hink]

Re: unusual noise

Thanks to all of you again for your input concerning my problem with the mercruiser1 outdrive.<br />By following your suggestive thoughts, I think I have located the source of the screaming,grinding noise,although it does surprise me,if it is true!<br />I think the noise was caused by interference between the output shaft splines and the shift cable.<br />I peeked through the gimbel bearing into the cavity containing the coupler to see the hub splines of the coupler. I saw immediately a jumble of wire that looked as though a wound cable had been pressed on the end to expand it and then had caught on something to twist it in all directions.I do believe the reverse shift cable has failed. It was installed a couple of years ago when I was having some problems with the shift control.The pieces of wire that I found earlier match this mess of wire for size and flexability.<br />I now know what needs to be done, the question is, how to go about it without destroying the boat?

 

[John Hink]

Re: unusual noise

Hello again to you who have been trying to feed information to me about this screaming, grinding<br />noise!<br />I was able to get a closer look at what I thought was a pile of wires from a cable. Oh, did I get an eyefull. The wire turns out to be all that was left of the internal splines of the drive coupler. What a surprise! <br />My next question is, will the coupler come out through the gimbal bearing cavity? Will I still have to remove the engine?<br />I still need your help with the information, and thank you in advance.

 

[Don S]

Re: unusual noise

You have to pull the drive first, then pull the engine, remove the bellhousing just to get at the nuts on the coupler. <br />When you put it back together, be sure to replace the rear motor mounts and then realign the engine when you are done. You will get the new style motor mounts and they may or may not require the shims under them. Read the instructions that come with the mounts.<br />With a 72 boat, the rear mounts have probably gone soft or broken which caused the splines to go away. Check the drive shaft splines also. They are probably thinner and it needs replaced also.<br />Alignment after all that is something that "MUST BE DONE" unless you want to replace the coupler again very soon.<br />PS: They cost about $350, so get it right.

 

[John Hink]

Re: unusual noise

I can see what you are speaking of. I definitely do not wish to do this chore again!<br />Glad you mentioned the rear mounts! I had not thought of them.<br />Any idea of the price of the alignment tool? Can one be fashioned from hardwood if I had the specs for it?

 

[Don S]

Re: unusual noise

Wood wouldn't last very long when you try to align an engine with new mounts and coupler. Stick with the real thing<br />Here is one place you can get one for about 75 bucks. <br /> http://www.mercstuff.com/page16.htm <br />I've never tried, but you might find one on ebay. The alignment should be checked every time the drive is removed (which should be at least yearly for maintenance) this way you can check that nothing has gone out of alignment. You should also lube the splines on the shaft every 100 hours or yearly. 50 hours if trolling a lot.

 

[John Hink]

Re: unusual noise

Thanks Dan, for the reply.<br />I can turn the tool from mild steel rod if I had the specs. Trade schools had a ball wasting time on a shop lathe, remember those good times, Dan?

 

[John Hink]

Re: unusual noise

Don, I apologise for the mispelling in your name.<br /> <br />John Hink

 

[Don S]

Re: unusual noise

Here is the dimensions for the buisness end between the gimbal bearing and into the coupler. The handle and length should stick out of the bellhousing about a foot, just to make it easier to use.<br /><br />

 

[John Hink]

Re: unusual noise

Thank you for the spec sheet on the tool.<br />It is appreciated by this wanna be.<br />John Hink