No fwd or rev with Volvo Penta SX

[muc]

Sorry to hear it's still having problems. Couple of things to check. I would have thought the shop has done this already, but maybe not?

At the back of the drive, disconnect the shift cable from the linkage and try to push and pull the cable in and out. Should be less then 1/4" of play.

Next is to follow Volvo's procedure to check for the correct amount of stroke.

1. Move remote control handle to the wide-open-throttle position in forward gear to retract the shift cable. Pull out cable core wire to remove end play. Mark cable core wire at end of casing.

2. Return remote control shift handle to the neutral detent position.
Measure and record the distance between mark and end of
casing.
3. Mark cable core wire at end of casing with control in the neutral
detent position.
4. Move the remote control handle to the wide-open-throttle position
in reverse gear to extend the shift cable. Push in on cable core wire
to remove end play. Measure and record the distance between
mark and end of casing.
• The distance between forward and neutral must be no less
than 1-1/4 in. (31,8 mm) and no greater than 1-3/8 in.
• The distance between neutral and reverse must be no less
than 1-1/4 in. (31,8 mm) and no greater than 1-3/8 in.
Note! Check your remote control installation instructions, if
your measurements are not within these specifications.
Make sure the cables are attached correctly inside the
control box before continuing. All control boxes must
meet these minimum and maximum specifications in
order for the shift system to function properly.

 

[highpowerdad]

Thanks Muc, I am preparing to just change out the controller and cable anyway, I mean, what else could it be and it looks pretty simple to do...? Yesterday I ran the boat around the lake again, brought it in to the shore with a hard right turn, and it was fine... still had forward and reverse, then when I moved the steering back to center, it wouldn't go into gear again. then when I lifted the drive and put it in gear, not running now, the prop went into gear, and then when I put the drive back down, and started the engine, I had forward and reverse again...so unless there is something inside the drive that is sensitive to moving the drive left-right, up down (or maybe the stop/start), then it has to be something in the cable and box, even if it looks like it is good. I have not done the push pull with the cable disconnected, BUT with it connected I would guess there is a 1/4 inch of slop. Again, thanks for your help, I would like to think I am getting close to the answer. I just ordered a Teleflex extreme 3300 type cable with the 10-32 on both ends, I am hopeful it will be a drop in replacement...

 

[muc]

Agree that your symptoms are pointing to the cable or controller. Your boat is one of the easier ones to do this job. But it can still be a good bit of work.

I still recommend that that you do the testing first. I have spent many years advising young technicians to “test first, replace second” there are many reasons for doing it this way. And it your case the tests are pretty easy. I would also check the cable mounting at both ends. Grab the cable jacket between the pivot housing and transom and try to move it in and out, also do this near the controller. It shouldn’t move at all.

One thing that concerns me. Fairly rare for a controller or cable to fail this way. Suggest that you pay close attention to how the cable is routed and secured. No tight bends and cable free to move for the first 2ft from the controller. Also make sure that the throttle cable isn’t trying to push the throttlebody closed too hard.

 

[highpowerdad]

So…I am waiting on the shift cable, but after running the boat today, I have convinced myself of 2 things. First, there is no way it could be the shift cable or control box and Second, it has to be the shift cable or control box, it’s the only thing left…So what does it do, when it is first running, it is good to go, shifts smooth and instant. After I have run it for a while, at cruising speed, it will not go back into forward or reverse after taking it out of gear, but sometimes it will go into gear once or twice, but as soon as I turn the steering wheel it will not (never pops out of gear, but once shifted out of gear, will not go back in. Move the drive up and down, side to side, and let it “cool” for 5-10 minutes, and it is all working again… When it is NOT going into gear, the shift cable is still turning the linkage arm on the back of the drive, and it looks like a full throw. New cones, cups, gears, lube…buy Volvo Penta certified mechanic. I will change the cable and control box out when the cable gets here Sunday, but I am not holding my breath it will fix it. I just cannot believe that this hasn’t happened to someone else, these SX-Ms have been around for a long time…I would say the lube is overheating, but that doesn't make any sense either. ​

 

[muc]

Only other thing that comes to mind. Maybe the lube is getting aerated ? After a long run, you could pull the level plug (slotted screw by shift linkage) and see if the lube is foamy.

 

[highpowerdad]

Maybe...just maybe...but I can't test for a few days...if it isn't THE problem, than it would have been another problem soon. I uploaded the photo, there was a break in the shift cable, a foot from the end, just about as it exited the boat, all rusty, about 1 inch long break longways...not sure how this would cause the problem but I will know in a couple days...new control box and cable is in, just need to fod check for that wrench that I dropped that must have been in my pocket when I was pulling the cable, heard it drop, just can't find it, out comes the endoscope...that and the cotter pin was not even bent on the throttle cable, just waiting to fall out..​

 

[dypcdiver]

The shop should have spotted that. You might have to keep quiet as they have been so helpful.

 

[muc]

Please don't change the font size. I have enough trouble seeing the screen as it is.

Very surprised that didn't show up in the shift cable test. Could easily be your problem. Guessing that bulge was inside the tube?

 

[highpowerdad]

So the problem is STILL there, I will put more detail in later, but it did the exact same thing, so I am fixing a lot of problems, just not the one that I need to. I now know how to make this happen at will, basically, run boat at cruise speed, bring into dock, take out of gear, move drive around or possibly wait a minute, and then try to put back into gear...no drive, but the linkage moves the shifter. Wait 10 minutes, and it is all good again, like nothing is wrong. Wash, rinse, repeat...Oil looked good, I checked it this last time when it stopped working, no foaming, only warm to the touch...etc, nice and clear.

Not sure what is up with the font...it did get small though...sorry about that.

 

[muc]

Remember that center bolt that was loose?
Starting to think that might one or two too many shims under it.

 

[highpowerdad]

Remember that center bolt that was loose?
Starting to think that might one or two too many shims under it.

well that would be an interesting mistake. It would be easy enough for me to remove and count the shims and then re-install one less. The shop manual says shim to the gap PLUS three shims, so there should be more than three shims in there...the shop manual does not say how thick each shim is...are we talking about being sensitive to something like a couple thou? If there are not enough shims then I am sure other bad things would happen - interference with the shaft, but I am guessing it would be safe to remove 1 if there are more than 3 there.

What about the bolt being too short to start with? was there a change in the part through the years?

Scott R.​

 

[muc]

Don't know about the bolt, never had to replace one. $20.00 part if you want to be sure. P/N 897711

Shim are about 0.010" if I remember right. The feeler gauge and special tool recommendation in the service manual never worked very good for me. I used a different procedure from earlier drives. Don't know about changing this adjustment while the drive is assembled and still on the boat. Taking out to many shims would put too much pressure on the shift shoe --- I would think bad things could happen if you ran the drive like that.
The thing that makes me reluctant to recommend you play with the shift shoe shimming (besides the possibility of big damage) is that I would guess the symptom of too many shims would be delayed/harsh engagement when you shift. And you don't report that. But that's just a guess on my part.

I've never had a drive with your exact symptoms that wasn't fixed by what your shop has already done. So I'm at a loss as to what you should do next, other then take it back to the shop.

I've only had two drives come in that come close to your problem. One was a King Cobra (different drive but the shift system is very close) it had been to a few shops with an unusual intermittent no forward (reverse always worked) that was slowly getting worse. It had had a couple of clutches and one set of gears replaced that seemed to help for awhile. during tear down and inspection, the only thing I found was slight damage to the helix on the upper vertical shaft that the clutch rides on. Ruined one of my best files (very hard steel) trying to clean it up. Luckily the customer had a machinist friend that was able to clean up. Fixed it. Other one was a Volvo still under warranty. Same symptom from the day it was new, but only reverse. Found the same slight damage to the helix but in a different place. A new shaft from Volvo fixed it.

Could this be your problem? I don't know, I'm just throwing it out here as an example that all problems are fixable. Just takes time and knowledge.
Hope someone finds yours.

 

[highpowerdad]

Here is a photo of the bolt and shims, looks like3, so according to the manual, that would be the minimum...goes back to the shop Monday, I am hopeful they just swap out the whole drive...

 

[Scott06]

Here is a photo of the bolt and shims, looks like3, so according to the manual, that would be the minimum...goes back to the shop Monday, I am hopeful they just swap out the whole drive...

Good luck be interested to see how this plays out, tough issue especially if Muc is running out of suggestions.

the helix wear scoring is possible it’s hanging up probably not checked on reassembly?

 

[muc]

There are usually more than 5 shims. Because of the white sealant that’s used it’s hard to tell without removing the bolt and prying them apart.

 

[Lou C]

I'm seeing what looks like 6 shims....if you look really close...

 

[highpowerdad]

I'm seeing what looks like 6 shims....if you look really close...

Yea, zooming in on the original high res photo there is at least 5 and maybe 6...so that seems less likely that there is some odd tolerance issue going on...

 

[highpowerdad]

It's back in the shop now, along with the shifting problem, I notice the gear "whine" is getting louder, probably deserves it's own thread...I am assuming gear "whine" that that is louder than the motor and pretty "feelable" in the floor when at idle speed is not a normal caracteristic of an SX-M? since the gimbal bearing and u-joints were all new, and it doesn't change with steering angle, I assume it is in the drive itself...

 

[muc]

It's back in the shop now, along with the shifting problem, I notice the gear "whine" is getting louder, probably deserves it's own thread...I am assuming gear "whine" that that is louder than the motor and pretty "feelable" in the floor when at idle speed is not a normal caracteristic of an SX-M? since the gimbal bearing and u-joints were all new, and it doesn't change with steering angle, I assume it is in the drive itself...

Probably a good assumption.

Sorry to hear about these problems. Boating should be fun.
Hope that this is just a bunch of coincidences and your service provider can get you happier.

 

[highpowerdad]

Well, I have it back, they water tested it, duplicated the issue and decided to swap it out. they put on a new (reman) drive, pn is 3868892 and sn is 4202122548 which might make it a little bit younger than the other. They also water tested it with the replacement Started life as a 1.66, that is crossed out so I assume it is a 1.60, lower on it now, I could use a little lower gearing if it is a 1.66 still though. Will put it in the water Friday...they said they would call me in the fall when they figure out what is really wrong with the misbehaving one...More to follow when I get it in the water.