88 OMC Lower Unit clunk noise. Dog Slip?

[donwonnc]

Purchased this 88 Sunbird from first owners. 4.3 ltr V6 OMC Cobra drive. When putting into Forward slowly I began to notice one solid KLUNK noise or feel. If I powered up quickly, the KLUNK was limited to one or none. Called the sellers and they said that it had always done that one KLUNK. Took it to Marina, they verified that I had the recalled, replacement lower shift cable, red. They told me that they would try adjusting the shift cable. I got the boat back and the KLUNK noice/feel was gone for maybe a season and now has returned. No problems at high speeds. I am afraid to try to go slow and waiting to hear more than one KLUNK. Marina said run it till I need new lower unit gears. Along with this KLUNK, it is very hard to get out of forward gear like when docking, I have to yank the tar out of it, to go into neutral I will re check, but I don't recall any problems with the switch that briefly stalls the engine, to make shifting easier, ESA? I read the (stuart hastings??) report, about the recalls, the Dog that engages the forward gear is my suspect.
Also, I get 10-20 gallons of water in the boat and none is from wet swimmers coming aboard. Should I be taking on any water through this I/O drive? I have purchased a Bellows Kit, I have a Gimball bearing just incase. I have never removed any out drive, my specialty is Printing Presses. I have looked at building some kind of cradle to help me hold the drive as I do not want to get hurt. I imagine the bellows are real bad and I want to see the lower end of the shift cable, the bell crank area, clean it, maybe install a new cable, or do I. What would you guys do? Funds are tight. I have read OMC's reputation, so I apologize if I am asking a previously answered question. I do have an OMC service manual. I think I have a very good engine, thus my reason to give this boat a little TLC.

 

[airdvr1227]

Re: 88 OMC Lower Unit clunk noise. Dog Slip?

If your drive klunks after you put it in drive it will eventually fail. The fix is the Hastings report and having the cable adjusted properly. The water issue is simple...you have a leak. You should not be taking on that much water. The most common problems are the thru hull connections like the bellows and shift cable etc. Before attempting to work on this unit you should get a OEM service manual.

 

[donwonnc]

Re: 88 OMC Lower Unit clunk noise. Dog Slip?

airdvr1227 Thank You so much for responding. I feel that I must say this: After some recent family tragedies, I am mentally down right now, making even the smallest of task more difficult. I do have an OEM OMC Service manual and last night I read about adjusting the shift cable, trying to understand what forces from what direction, pull or push the dog into the gears. I know that hearing this one klunk when powering up indicates a problem and if I can replace a cable or make an adjustment now, I would rather do that than not worry about it until I need a whole set of lower unit gears or a lower unit trade in. I don't have specialty tools for this type of work other than some snap ring pliers that I used on printing presses. I learned offset printing presses inside and out, so I am confident with a clear mind that I can do most anything, just don't have the clear mind right now, so I would be taking notes, drawing little pictures and taking photos if I remove my outdrive which I am itching to do, as I mentioned I do have a complete bellows kit. How much does the oudrive weigh?? My book says use the fluid dipstick hole as a lifting point, but the whole looks worn, the threads are not strong so I am inclined, not to use a lifting bolt in that hole. I am going to the local license plate agency today and see how much it is going to cost me to get a plate on my trailer, and to the local marine dealer to ask about boat registration and see if I can pick them for any information. The last time I asked any Marina about working on my boat, they said they had no I/O mechanics. I do appreciate anyone that has the patience to help me and comment.

 

[cds4byu]

Re: 88 OMC Lower Unit clunk noise. Dog Slip?

I have an 89 OMC stern drive. I, too have had difficulty with shifting. I followed the Hastings sequence, and found that my bellcrank was bent.

I also found another problem on my system. THe trunnion on the shift cable at the shift/throttle control was worn. THat introduced play into the shifting and caused problems. I'd suggest that you check your cables where they connect to your shifter.

 

[donwonnc]

Re: 88 OMC Lower Unit clunk noise. Dog Slip?

Good info that I have not covered, thank you fellow cadet. When you test your ESA switch, can you notice the engine stalling or slowing in RPMs? I have broken one of my support clips that snap onto the trim arms so the unit will not settle during towing, so last night I was looking on e*ay and I saw there are tools for the bell crank and lower cable adjustment, so I will read my OEM manual to see what that is about. I tried to get some information out of my local Marine dealer, but they were evasive, however they do have I/O mechancs and would do the work for me. Since cost of registration and trailer plate was minimul, I think I will change some fluids and make a trip to the lake. I will check the cable where it ties into the shift lever per your advice before I go, and take a short second maiden voiage to confirm my problems, before I remove the units. Thank You for sharing.

 

[airdvr1227]

Re: 88 OMC Lower Unit clunk noise. Dog Slip?

Not as heavy as they look. 2 guys can handle it easily.

 

[Idlespeedonly]

Re: 88 OMC Lower Unit clunk noise. Dog Slip?

When you shift into gear It needs to be a quick and firm motion. The multiple clunks you are hearing are the dogs ratcheting, which is not what you want to hear. The clunk you are experiencing while under power are the dogs disengaging.

 

[donwonnc]

Re: 88 OMC Lower Unit clunk noise. Dog Slip?

Not multiple klunks> No issues at WOT Just one klunk 1 second after the initial engagement when shifting into Forward. I shift into forward, the boat rises up and travels 10 to 20 feet and I feel the single slip, then past that it is running fine. Very difficult to pull shift lever out of FORWARD when stopping the boat. I am paranoid, to cruise at slow speeds, as I am just waiting for it to slip more than once.
I drained fluid from lower unit and I got about a half cup of water??? I broke one of my plastic trim arm clips, sticks that snap onto the trim arms to keep the unit from settling down when towing. IF anyone wants to sell me a set or one. I greatly apreciate the replies and help.

 

[HT32BSX115]

Re: 88 OMC Lower Unit clunk noise. Dog Slip?

Not multiple klunks> No issues at WOT Just one klunk 1 second after the initial engagement when shifting into Forward. I shift into forward, the boat rises up and travels 10 to 20 feet and I feel the single slip, then past that it is running fine. Very difficult to pull shift lever out of FORWARD when stopping the boat. I am paranoid, to cruise at slow speeds, as I am just waiting for it to slip more than once.
I drained fluid from lower unit and I got about a half cup of water??? I broke one of my plastic trim arm clips, sticks that snap onto the trim arms to keep the unit from settling down when towing. IF anyone wants to sell me a set or one. I greatly apreciate the replies and help.

When putting into Forward slowly I began to notice one solid KLUNK noise or feel. If I powered up quickly, the KLUNK was limited to one or none.

Howdy, Welcome Aboard!

First of all NEVER EVER shift slowly into gear (FWD or REV)..... EVER!! (This will eventually damage/destroy the shift dogs)

If the drive is hard to pull out of gear you have a either a bad or corroded lower shift cable and/or a non-functioning ESA.

If it's the ESA, you will eventually damage the shift cable if it's not already and the shifting will get much worse....and that will damage the shift dogs eventually. (you may be there already)

You need a new shift cable, ESA replacement (or ESA switch(s) repair/replacement) and the drive resealed.

I broke one of my plastic trim arm clips, sticks that snap onto the trim arms to keep the unit from settling down when towing. IF anyone wants to sell me a set or one. I greatly apreciate the replies and help.

You can buy those online right here on iBoats and other places.....
T-H Marine Trailering Clips (Inboard Outboard Motor Support) - T-H Marine Supply TC-1-DP - iboats




If you solicit other people here to sell them to you, you'll run afoul of the rules, get "spanked" and get your post edited by one of Moderators!


Regards,


Rick

 

[HCMQA]

Re: 88 OMC Lower Unit clunk noise. Dog Slip?

Also if the klunk is that pronounced your idle may be way to high. Should be down below 600 rpm.
Drive is easy to pull. Harder to put back on.
If it clunks at all while under way as you describe I would not use it again until you get it figured out.

 

[donwonnc]

Re: 88 OMC Lower Unit clunk noise. Dog Slip?

Everything I have learned and suspected is pointing to the lower shift cable and I will check cable connections at the contol lever, Thanks cds4byu. I turned the drive full to port and looked into the pivot housing where I could see the U-Joint and Exhaust Bellows, but I did not see any shift cable bellows at all, if it should be attached to the pivot housing like the larger ones. I plan on taking another look with a small mirrow and I will take a photo to post, but I did not see a shift cable bellows at all during my first look. The Red cable went through a post, much like the exhaust bellows attachment point but smaller, and there was no rubber boot over that post.

Should I worry about this small amount of water that came out of the lower unit. This boat has been locked up in storage for 7 years, during a nasty divorce, but if my memory serves me well, I have seen this small amount of water before, when changing the lower unit gear oil. I do remember striking something (wood I think) damaging one prop blade, but I had my buddy tow me back so I didn't run the unit with an off balance prop, then changed out to new prop.

ESA -- I have read all about it, and I tested it years ago, but I don't remember a noticable change in idle when I depressed the ESA. I will check it again.

The idle speed, Is this something that you pros can do by ear, do I need a tachometer or timing light? I don't mean to ask stupid questions and I sure don't want to get in any trouble soliciting for parts or for any reason. Thanks for the link Admiral (Rick), as to where I can get those Trailering Clips, I guess I didn't know what to call them as I couldn't easily locate them.

As far as removing the drive, I was thinking that I could drain fluid, remove the prop, then be able to pull it off myself and just lat it over onto something soft, but now I am thinking that I do need some kind of support/hoist to assist me, especially when I go to put it back on. I viewed a video on U-*ube titled, "How to pull an outdrive off using a pickup truck." I'll just say that I would have been embarassed to post that video. Looked like an accident waiting to happen. I do Thank everyone who helps me. If I don't Thank you specificly, it's just an over sight.

Donnie

 

[HCMQA]

Re: 88 OMC Lower Unit clunk noise. Dog Slip?

That video is useless.
The cobra drives come right off in minutes. I use a black and decker workmate to hold my drive once its off. Drain it, take the prop off, remove the six nuts and pull. It is about 70-80 lbs.
Idle is adjusted by using the tach while in gear in the water. If your tach is bad you will need a timing light with one.
The shift cable bellows is in the boat at the end of the rubber hose that the shift cable comes through. What you described in the pivot housing sounds correct.

 

[donwonnc]

Re: 88 OMC Lower Unit clunk noise. Dog Slip?

Thank you for confirming that the shift cable boot is inside the boat. In my bellows kit, I have a couple of zip ties, are they for the shift cable bellows? I was mistaken (oops), the hole that I think the shift cable goes through is not a post or an outty. it is a recess or inny. I have photos. Near the bottom of the second photo, shows the hole that the shift cable goes into from outside. ( I think it is the shift cable?) See the second photo showing the red cable. Access to the back half of my engine is difficult, Had to repair the power steering cooler one time, and only after it froze, bustedd and leaked water did I know that it was bolte to the bak of the engine. This bellows for the shift cable is going to be a pain to get to, glad I have my lounge seats out. In my second photo of the red cable, if that is infact the shift cable then where is the bell crank in relation to photo, just outside of view to the left??

 

[donwonnc]

Re: 88 OMC Lower Unit clunk noise. Dog Slip?

What I found when out drive removed. I made a simple wood drive stand that worked great. Recap my story. Second owner of a 1988 4.3 ltr V6 OMC cobra drive. When I first bought it, I noticed that after I put the boat in forward and started under way, the clutch dog seemed to slip one time, then no more, at WOT in curves or anything, no problems in reverse. I called the first owners and they said, that it had always done that but they didn't think it a problem. I took the boat to a local marine service and they confirmed I had the replacemnt transom shift cable and told me that they may be able to adjust it. I don't know what they done, if they removed drive or just made adjustments under the hood on the engine brakett. The one slip of the dog was gone for one season, but it came back and I am trying to correct the issue before my lower unit gears and dog are ruined. I have studied the Hastings report, my OEM manual and the forum archives to no end. I am selling the boat, but trying to eliminate this dog slip before taking possible buyers out on the boat. The drive came off fairly easily. There didn't seem to be water getting into the U-Join bellows. U Joints seem good, no play, no rust. There was allot of grease behind the gimball bearing from where I had been pumping it in through the tube on starboard side. The area all around the U Joint bearing carrier and in the cavity where the bell crank lever and plastic cable guide had allot of sludge, it looked like ajax or comment almost, and looked as if it could be impeding on the bell crank range of motion, so I was glad to see the crud. It may have been 20 yrs since the shift cable was replaced, so I have one ordered. I guess a cable can be weak or fail somehow other than a complete break. Before all this, I noticed that my boat took on some water each trip, so I bought a bellows kit with gimball bearing. I am unsure if I will replace the gimball bearing, I will inspect it carefully. The 7 & 9/16th deminsion required on the engine side of the transom shift cable was spot on. When reacing into the shift shaft area of the drive and manually changing the gears seemed to work fine. Should I let a few drops of any oil to run down the shift shaft to lubricate it where it enters whatever it enters? Back to water the leak, where I take on a little water each trip to the lake. I put the plug in the boat and ran water into the bilge and after it got to apr 8 inches in depth of the bilge, I saw water streaming out between the boat hull and the (gimball ring?) first part that touches the boat on the back, is it the Gimball Ring? I bought the 1/2" allen wrench needed to remove the pivot pins on each side of the pivot housing. I have to see more, I have to find out where the leak is, maybe I can just tighten up some bolts that go through the transom and slow down the leak if that is where water is coming in. Can I do this following test on the water - Take the throttle cable loose at engine, then shift all the way into forward and manually accelerate while listening to see if the dog slips? I have photos from the drive removal, and of the slurry found. around the cable guide end, if any photos would help please ask. I am eager for advice or constructive critisysm.