1987 2.3L OMC makes "bump" noise every 6 seconds...

Status
Not open for further replies.

ALS30

Cadet
Joined
Jun 4, 2002
Messages
8
HELP PLEASE! 1987 Bayline w/ 2.3 liter Ford motor and OMC Cobra outdrive. Runs GREAT but while under power there is a significant "bump" noted. I fear it may be the "clutch dog" assembly in the lower unit but wish to get confirmation before disassembly...<br /><br />Thanks,<br /><br />ALS30
 
D

DJ

Guest
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

ALS30,<br /><br />It may be just that-clutch dog. I believe OMC had some issues with those. You may also want to check your shift linkage, it is tricky to adjust.
 

ALS30

Cadet
Joined
Jun 4, 2002
Messages
8
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

Thanks djohns,<br /><br />It was indeed the "clutch dog" thing. It appears the clutch dog's teeth tend to round off over time.<br /><br />My only problem now is according to the manual there is a special tool for measuring the shift rod prior to re-assembly. The local boat place wants $30 just to let me measure the silly thing...<br /><br />Thanks again,<br /><br />Jeff
 

jimmyvan

Cadet
Joined
May 28, 2002
Messages
8
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

i also have just had that "bump" starting to happen, how much time did you have in replacing the dog?
 

ALS30

Cadet
Joined
Jun 4, 2002
Messages
8
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

Hey,<br /><br />It took a couple of hours with the help of a manual to take the lower unit appart and put it back together. It took about a week to get the parts... OMC doesn't seem to carry a very good reputation in the boating comunity.<br /><br />Let me know if I can be any help with your "bump"
 

cbcsr

Cadet
Joined
Sep 25, 2001
Messages
10
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

Als30,<br />I have an 89 3.0L that has developed the dreaded clunk. A mechanic told me(without looking at it)<br />that the clutch dog and the gears would have to be replaced $875 parts and labor. new shift cable installed would be $325(even though I have the updated cable).Did just the clutch dog replacement fix your problem? What was the cost? Where did you get the parts? What manual did you use? I can follow directions but changing oil and sparkplugs are my only mechanical skills. Could I complete the job? Any information would sure help<br />as I really can't afford the $1200. <br />Thanks<br />cbcsr
 

ALS30

Cadet
Joined
Jun 4, 2002
Messages
8
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

Its a pretty involved task. I'm not sure you need a new shift cable if you already have the updated one. I used the Clymer manual and it talked me through it pretty much step by step. The biggest problem I had was getting the two large snap rings out of the lower housing...<br /><br />I won't know until this weekend if it fixed it though...
 

jimmyvan

Cadet
Joined
May 28, 2002
Messages
8
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

LAST WEEKEND I REPLACED THE DOGS, YOU WERE RIGHT! THOSE SNAP RINGS TOOK THE WIND OUT OF MY SAILS. I FOUND A PAIR OF 11" NEEDLE NOSE PLIERS AND THEY CAME RIGHT OUT. TOOK IT OUT ON THE LAKE AND RUNS WITH NO BUMPS, BUT NOW IT IS HARD TO SHIFT. MAYBE YOU WON'T END UP WITH THE SAME EXPERIENCE
 

sea wolf

Lieutenant Junior Grade
Joined
Apr 3, 2002
Messages
1,219
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

if it's hard to shift the shift cable is probably out of adj. there is a web site devoted to cobra shift problems. the link has been posted here. go to search & u should be able to find it. you'll need to print it out as it's a pretty involved procedure.
 

P.V.

Chief Petty Officer
Joined
Mar 14, 2002
Messages
452
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

OK, OMC had a recall in '91 that related to an updated shift cable AND if a customer experienced a "clunking" type noise, to also update the shifter, forward and reverse gears . The clunking is/was the shifter not fully engaging into the bottom of the dogs of the forward gear. The orginal gears were 2 degree back-cut and the updated ones had a 5 degree back-cut. This ensured that once the gears' dogs went into engagment, they sucked themselves into each other and did not partially engage. Or disengage. <br /> There is a new adjustment procedure that OMC came out with in the waining months before the backruptcy that made the adjustments much EZ ier to do. But, all the cabvle measurements and linkages must be up to par...... It's not a hard system to fix, but you must know all the things to check. Yes, a knowledgable dealer nearby would be helpful. Hope this helps you . It sounds like you need the "full-meal deal" !!!!!
 

ALS30

Cadet
Joined
Jun 4, 2002
Messages
8
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

The OMC "clutch dog" is indeed a poor design at best. I found the edges of the three teeth on the forward gear part of the dog to be partially worn. Just enough to cause it to slip a notch, thus the "bump" while under a load as in moving through the water. I, being an old redneck country boy, discovered that it is possible to turn the dog around (with a slight bit of modification) and it has fixed my forward "bump"... The shift cable part of it is truly a pain in the rump but I must admit the manual I bought was well worth the expense... Thank you all for your help!
 

sea wolf

Lieutenant Junior Grade
Joined
Apr 3, 2002
Messages
1,219
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

al, what manuel do u have? i'm looking for 1.
 

ALS30

Cadet
Joined
Jun 4, 2002
Messages
8
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

That would be the Clymer's manual for OMC Stern Drives. I ordered it out of a Overton's catalog for about $30
 

6MISFITZ

Petty Officer 1st Class
Joined
Nov 16, 2001
Messages
290
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

I have no clunk in forward at all but when shifting into reverse it takes 3-4 extra seconds for the clutchs to stop clicking. <br />Adjustment?<br />My boat is an 87 3.0L with Omc Cobra. Not a 400 or 800.<br />What does this updated cable look like vs. the old one?
 

BigBabyLou

Petty Officer 2nd Class
Joined
Apr 9, 2002
Messages
129
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

Sea Wolf, if you want to order the manual from Overton's, you'll have to search hard, it's not easy to find it using their search engine. Or follow this link http://overtons.com/cgi-bin/overtons/order/pdetail.cgi?23244++2Y7 which will take you directly there. The price is $25.99 but S&H seems high - $8.99.<br /><br />You can always get the manual cheaper at used book websites, like half.com etc. I get all my manuals from there. If you want, I can send you a $5 discount coupon for that site.<br /><br />Take care<br />Lou
 

ALS30

Cadet
Joined
Jun 4, 2002
Messages
8
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

It is my understanding that the original cable is black and has a spiral appearance (either its coated with something that looks spiral OR it has a spiral cover over it). The replacement cable is red...<br /><br />The only real trouble I had was with setting the shift rod (out of the top of the lower unit). There is evidentally a OMC "special tool" for measurement. I marked my old one before disassembly... <br /><br />Sound to me like maybe your shift linkage is off a wee tad in the reverse aspect. <br /><br />Thanks,<br /><br />ALS30
 

P.V.

Chief Petty Officer
Joined
Mar 14, 2002
Messages
452
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

The very first cable (the one that was specific to the recall) was a "black, ribbed" cable. They did have a "smooth" cable for a while that was black, but for the most part, you should have the red cable. Note, that the red cable can also fail and cause problems. So, it needs to be checked. Again, I would suggest you have the outdrive cable checked with the outdrive off, the proper locating tools installed to ensure that all is within specs. There are quite a few service bulletins out about shift system checks and rectifing problems. One of the most common problems concerning cable failures is the "missing" plastic sleeve that is supposed to be wrapped around the shift cable up inside the large tube from the outside to the inside of the boat. This "sleeve" allows the shift cable to "slide" inside the tube while tilting, trimming or turning the outdrive. Without this sleeve, you have a rubber coated cable rubbing/pulling/grabbing onto the larger tube. It will cause the smaller shift cable to pull itself apart at the mating point where the outer rubber casing attaches to the brass anchor point. Many mechanics don't install these sleeves correctly OR don't think they need to install them. As the cable starts to fail, shift adjustments are out of spec. Problems arise..... Again, you should have a good manual and a trustworthy season'd OMC tech for a friend.
 

6MISFITZ

Petty Officer 1st Class
Joined
Nov 16, 2001
Messages
290
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

I appologise for asking a question in the middle this string and not starting a new post but I follow all the Omc posts and this was close to my model.<br />Thanks for the response,<br />Mike.
 

ALS30

Cadet
Joined
Jun 4, 2002
Messages
8
Re: 1987 2.3L OMC makes "bump" noise every 6 seconds...

Can someone help me find any OMC update/recall info... What has been recalled/replaced etc???<br /><br />Thanks,<br /><br />ALS30
 
Status
Not open for further replies.
Top