4.3L Mercruiser with a few issues

[WhiteyFlex]

So after 6 years of not having a boat I jumped back in the lake and bought a boat. Picked a 1989 Regal Sebring 195 for a solid price. Previous owner took immaculate care of it. But I am having a few issues out of the gate. Below are the upgrades that were made by PO and the issues I'm currently having.

4/24/01 - steering cable replaced
7/16/03 - shift cables replaced
5/10/09 - replaced original 4.3L V6 with a new 1996 4.3L V6 vortec (and yes the engine was still new although 13 years old) & did most of the other major stuff like gimbal bearing, pumps, carb rebuild, alternator rebuilt
7/24/17 - new drive belts
5/14/20 - Rochester quadrajet carb rebuild, new trim switch and impeller kit

1. Stalling issue - This is the biggest problem at the moment. Had the boat out 2 times and it keeps stalling when shifting into gear. Doesn't seem to matter if it's forward or reverse. Also coming out of gear back to neutral it stalls everytime too. Overall it seems to run good once you have the RPM's up and in gear. The engine will even die occasionally just in neutral if I throttle up and let it back down to idle.

2. Vibration when turning under a load - so if I'm cruising along and I go to turn, I get a deep vibration feel in the boat. Doesn't really seem to do it if I'm going in a straight line. Vibration sensation is there turning left or right

Thanks, Matthew White

 

[Scott Danforth]

first, welcome aboard

on to your issues

first, adjust your lower shift cable. if it doesnt adjust properly, replace it

2nd, pull your drive and inspect the U-joints and gimbal. you need to be pulling the drive every year to check these things and the alignment. so start now. you will find that one or both of them are on the way out.

 

[alldodge]

1. Agree, and check the shift interrupter switch and its adjustment

 

[tpenfield]

:welcome: to iBoats . . .

What Scott and AD said ^^^^

Hopefully a solid boat came with that solid price

Older boats tend to keep you busy, so stay on top of things.

 

[Scott Danforth]

with a new boat, you have a monthly payment of a few hundred dollars if you financed your boat

with a used boat, especially one older than 15 years, you have a monthly repair bill

 

[WhiteyFlex]

So I've adjust the shift cables 3 times now.
The first I did was based on the video from YouTube where the British bloke talks about using the 6" rule for the barrel to end length.
https://youtu.be/-s_tgevX2aI
The next time I tried the procedure found in the seloc mercruiser repair manual for 1985 and newer mercruisers. That one worked reversing the boat off the trailer. After that it wouldn't work at all. After trying for 30 minutes at the dock I adjusted the remote control cable again and was at least able to get it running after a few more attempts.
After looking through my 1989 original owner's maintenance supplement I found a spot that had a different style cable adjustment where you adjust the lower shift cable with the end eye still attached, then once lower cable is adjusted you adjust the control cable using 4 counter clockwise turns and working from there, making small tweaks until it right but no more than 4 clockwise turns for adjustment.
2 questions for you:

Can the shift interrupt switch be bad itself and need to be replaced?

When I pull the drive to check the bearings ( I assume you mean to pull the out drive off? I've never check gimballs or u-joints on a boat. What do good ones and bad ones look like?

 

[alldodge]

where the British bloke

That's different achris is from down under

Can the shift interrupt switch be bad itself and need to be replaced?

Yes, the switch can cause all these issues

When I pull the drive to check the bearings ( I assume you mean to pull the out drive off? I've never check gimballs or u-joints on a boat. What do good ones and bad ones look like?

The drive should be pulled and alignment check every year, but at least ever 3 years. I do mine every year

Reach in with your fingers and rotate the bearing, it should feel smooth as silk

Check the U-joints for smoothness and if they have grease fittings, grease them

 

[Scott Danforth]

So I've adjust the shift cables 3 times now.
The first I did was based on the video from YouTube where the British bloke talks about using the 6" rule for the barrel to end length.
https://youtu.be/-s_tgevX2aI
The next time I tried the procedure found in the seloc mercruiser repair manual for 1985 and newer mercruisers. That one worked reversing the boat off the trailer. After that it wouldn't work at all. After trying for 30 minutes at the dock I adjusted the remote control cable again and was at least able to get it running after a few more attempts.
After looking through my 1989 original owner's maintenance supplement I found a spot that had a different style cable adjustment where you adjust the lower shift cable with the end eye still attached, then once lower cable is adjusted you adjust the control cable using 4 counter clockwise turns and working from there, making small tweaks until it right but no more than 4 clockwise turns for adjustment.
2 questions for you:

Can the shift interrupt switch be bad itself and need to be replaced?

When I pull the drive to check the bearings ( I assume you mean to pull the out drive off? I've never check gimballs or u-joints on a boat. What do good ones and bad ones look like?

just so you know, Seloc and clymer make the worst manuals in publication. not only is there missing information, there is mis-information.

I would recommend the factory manual.

and yes, the switch can be bad

 

[isaacs]

Couldn't you temporarily short out the shift interrupt switch to see if that's what is causing some of your problems?

 

[achris]

Hi Matthew, I'm 'the British bloke', and I've never been to Britian. (Born and raising in Australia)...

Stalling going into gear is usually a bad shift cable or the bushing on the upper shift Shaft. Pull the drive and see if it still does it.

Chris...

 

[WhiteyFlex]

Well g'day Mate. I apologize for the British mixup. I should know an Australian accent by now with all the BBC shows my wife watches ;-)

Thanks for the heads up on soloc manuals, I'll stay away from those.

So I checked the shift cable for tolerance and it seems to be within spec like you state in the video. I'm going to do the adjustment procedure I found in the original owner's manual, and replace the interrupter switch just to be safe. If that doesn't work I'll look into the shift cable again. When you say, "pull the drive and see what it does it", what do you mean pull the drive?

In regards to the vibration , When alldodge references "Reach in with your fingers and rotate the bearing, it should feel smooth as silk" where am I reaching to? What part am I reaching?

 

[Baylinerchuck]

Well g'day Mate. I apologize for the British mixup. I should know an Australian accent by now with all the BBC shows my wife watches ;-)

Thanks for the heads up on soloc manuals, I'll stay away from those.

So I checked the shift cable for tolerance and it seems to be within spec like you state in the video. I'm going to do the adjustment procedure I found in the original owner's manual, and replace the interrupter switch just to be safe. If that doesn't work I'll look into the shift cable again. When you say, "pull the drive and see what it does it", what do you mean pull the drive?

In regards to the vibration , When alldodge references "Reach in with your fingers and rotate the bearing, it should feel smooth as silk" where am I reaching to? What part am I reaching?

Pull the drive off the back of the boat. If it hasn’t been done before it’s going to be tightly fastened. Make sure the drive is in forward gear before you attempt to pull it. The dive shaft goes through the gimbal bearing and into the coupler at the back of the engine. Pulling the drive exposes the gimbal bearing and universal joints. This is what you are inspecting. You also can inspect the bellows at that time.

 

[Rick Stephens]

With the drive off, you can inspect and grease u-joints, inspect gimbal bearing, and bellows. Note any water intrusion. Replace the gasket and water passage o-ring. I like to give a coat of 2-4-C grease to all bare metal parts including the drive mounting studs and all of the driveshaft so I avoid corrosion.

While the drive is off you can also easily check that the shifting works smoothly and easily on just the lower assembly. You have to turn the shift shaft with your fingers while gently rotating prop enough to allow the gears to dog into full engagement. As with the statement that the gimbal bearing should be smooth as silk, the shifter linkage into the outdrive should also be smooth as silk.

 

[WhiteyFlex]

Ok, so after some investigative work here's what I've found:

this time I did the adjustment per achris YouTube video. Using his method sets the gear shifting very nice so its fully engaging forward and reverse. The lower shift cable is within measured spec and functions correctly. I believe the remote control cable is my problem. It measured 1/8" out of spec per his video. With the new shift adjustment the kill switch is mostly engaging in forward gear, but barely moves in reverse. I messed with the shift cable and adjusted it 10 times until I got the kill switch functioning both ways, but once I had that it wouldn't engage reverse anymore. So this winter I'll get new shift cables and I'll get a new kill switch just to cover my bases.
another thought: the boat is an '89 but the engine is a '96 vortec. Is it possible that the shift fork section isn't the correct setup because of the year gap, or should that not matter?

 

[Baylinerchuck]

Did you start with the shift cable in the lowest position in the adjustment slider? Once you found out it wouldn’t go into reverse fully, did you move the slider up until reverse engages?

The newer engine wouldn’t make a difference to the outdrive shifting.

 

[WhiteyFlex]

I took it out today for one last hurrah, and I can definitely say the shift cable is the problem.

@aChris's shift adjustment procedure worked better than any of the others I tried. While it wasn't perfect it worked well enough to enjoy a nice little family outing without too many hiccups. At one point my wife was driving and it just wouldn't start. I popped the engine cover and found the switch was halfway between the bottom and top seat. The shift cables are sticking and causing the switch to hang up in the kill section which is probably what's been happening all along. Toggled the switch both directions to loosen it up and she fired right up. This winter I'll replace the shift cables and the switch just for good measure. I'll also pull the drive and inspect the joints and bearings per you guys' recommendation.

Thanks again for all of your advice. It was awesome to be in the water with a boat that has an issue, and be totally calm because I know what the problem is and how to fix it. Also on the docket this winter is a wake tower, bimini & swim deck. Can't wait for those projects ;-)

 

[achris]

Remote cable CAN NOT trip the shift interrupt switch.

 

[WhiteyFlex]

If the remote cable isn't the problem, why was I able to adjust the remote cable and change the functionality of the switch? While the lower shift cable is a little sticky it measures within tolerance. The remote cable is 1/8" out of spec so by theory there it too much play in that cable which keeps the shift interrupter switch from moving all the way to the end of its limit.
When I adjust the lower shift cable in forward gear to 6" and subsequently adjust the remote cable to exact length & add the 4 clockwise barrel turns, the switch will function correctly drin forward but barely move in reverse because there's too much play in the cable. I messed around with the length on the remote cable several times until I had it working both directions an equal amount, but it wasn't fully hitting the limit of the switch like it should, just was going far enough to function reasonably well. But once I did that remote cable adjustment I lost functionality in the lower shift cable to where it would go into forward gear but not reverse. I even tried moving the lower shift cable lug up in the slot to help with reverse engagement but then it would nullify the remote cable adjustment I had just done. The original 6" lower shift cable adjustment i did never changed. And i constantly checked and re-checked to ensure it wasn't getting out of spec during this process.
by process of elimination it seems as though the remote shift cable is the problem. If I've misinterpreted something let me know.