MCM 5.7 Alpha 1995 Did I adjust the gear shift cables properly?

[Skidude17]

I have an MCM 5.7 Alpha engine serial# 0F598365. I bought this boat last year, and it ran ok, but I had issues with the engine dying sometimes when shifting to reverse. I followed achris' video on how to adjust the shift cables, but I have a spring guide assembly on that assembly that I didn't see on the engine in the video. When I went to adjust the upper shift cable, the spring guide assembly pushed the lower shift cable to its max extent. I removed the spring guide assembly to adjust the upper shift cable. Are my shift cables adjusted properly now?

red line = spring guide assembly
green line = upper shift cable
yellow line = lower shift cable

 

[Mad Props]

check out the SEI video on youtube, its much clearer

 

[achris]

The shift assister is designed to spring load the system towards neutral, and as such actually prevents full engagement when in gear, either forward or reverse. If you have any wear or slop in the system, it can cause a nil engagement condition. If you have a carb engine, then remove the assister and either toss it and put spacers or washers in it's place on the mounting posts, or do as I did with my 4.3LX, open up the assister and remove the springs. If you have an MPI engine, you will still need the assister as the ECU only cuts half the cylinders on a shift cutout event.

When the cables are adjusted correctly, the shift assister should just slip into place without any preloading. If it doesn't, you need to look at the cable adjustments again.

To check the assister, it should be in the 'centre/neutral' position, and require a force to both extend and compress it. The length between the anchor points should be as follows...

Chris......

 

[achris]

check out the SEI video on youtube, its much clearer

Wow, so many things WRONG with the procedures in that video. Where do I start?

First and foremost. You should NEVER engage gears, forward or reverse, without either the engine running or someone turning the prop by hand. If you look at a cutaway diagram of a gearcase you will see how the dog clutch works. Shifting without relative motion between the shaft and the gears can cause the flats on the gear and the clutch to line up, and you'll damage or even break the cable, or some other part of the shift system. Just, don't!

Second, he had to push the assister to get it to go in the mounting pins. If you have to push (or pull) the assiter, then the adjustment is out, start again! The assister needs to be completely relaxed when in neutral.

Third. What does moving the lower shift cable end anchor stud do? and how much does it need to be moved if you don't get full engagement? If you shift it all the way up, there's a chance you'll activate the cutout switch when going into reverse.

Fourth. Where's the check for cable/shift system excessive play (slop)? That is clearly stated in the manual as the FIRST check...

5. Nowhere in the manual does it state to back off the lower shift cable anchor pin nut '1/4 to 1/2 turn'... The nut should be tightened to the point where the cable isn't clamped, but allowed to just move freely on the pin.

I'm done here....

Chris....

 

[Bt Doctur]

I have an MCM 5.7 Alpha engine serial# 0F598365. I bought this boat last year, and it ran ok, but I had issues with the engine dying sometimes when shifting to reverse.

Did you pull the drive and inspect/lubricate the shift parts ? . Most problems are corrosion or a bad shift cable. The spring assist can be removed because sometimes it causes the shift core to wear thru the plastic core and bind when shifting .
Can test it by removing the spring assist and see if it shifts normally

 

[Skidude17]

I have an MCM 5.7 Alpha engine serial# 0F598365. I bought this boat last year, and it ran ok, but I had issues with the engine dying sometimes when shifting to reverse.

Did you pull the drive and inspect/lubricate the shift parts ? . Most problems are corrosion or a bad shift cable. The spring assist can be removed because sometimes it causes the shift core to wear thru the plastic core and bind when shifting .
Can test it by removing the spring assist and see if it shifts normally

I pulled the drive, and the shift cable is like butter. The other shift parts were lubricated properly.

 

[Skidude17]

Second, he had to push the assister to get it to go in the mounting pins. If you have to push (or pull) the assiter, then the adjustment is out, start again! The assister needs to be completely relaxed when in neutral.

Chris....

is the method they use for checking proper adjustment correct? If not, how should I go about doing it?

 

[achris]

Adjustment of the shift cable. That other video shows the same as mine, just with a lot less information as to WHY things are being done. If the cable adjustments are done right, the assister should slide on without having to push or pull it.

But as you have a carbed engine, gut the springs out of the assister and just use it effectively as a spacer.

Chris......

 

[Skidude17]

First and foremost. You should NEVER engage gears, forward or reverse, without either the engine running or someone turning the prop by hand. If you look at a cutaway diagram of a gearcase you will see how the dog clutch works. Shifting without relative motion between the shaft and the gears can cause the flats on the gear and the clutch to line up, and you'll damage or even break the cable, or some other part of the shift system. Just, don't!



Chris....

I just want to make sure I don't break my boat. I thought we were supposed to shift the gears not only throughout this process, but I also shift the boat in to forward when I remove the drive. Am I doing this wrong. Is the safety measure to have somebody spinning the prop while I'm shifting? That's going to be difficult for me since I do most of my maintenance by myself. Do you have any tricks?

I did as you suggested and removed the guts from the assister.

 

[Bt Doctur]

there are other tests for the shift cable. do you have the merc manual?

 

[Skidude17]

there are other tests for the shift cable. do you have the merc manual?

I do, and I will look it up. Thank you.

 

[Skidude17]

Adjustment of the shift cable. That other video shows the same as mine, just with a lot less information as to WHY things are being done. If the cable adjustments are done right, the assister should slide on without having to push or pull it.

But as you have a carbed engine, gut the springs out of the assister and just use it effectively as a spacer.

Chris......

I started it up on ear muffs today. It stayed in neutral fine while I adjusted the timing, but when I checked to see if it would shift into gear, it ground in forward, and died immediately in reverse. What’d I do wrong?

 

[Bt Doctur]

it ground in forward, Not enough fwd travel
died immediately in reverse Too much travel

TRY removing the main shift cable ,remove the lower shift cable brass tumbler from locking groove, manually shift into full fwd by pushing in the plastic sleeve while turning the prop CCW . Adjust barrel to the 6 inch measurement and install. Shift control box into full fwd .Attach sleeve end and adjust barrel to fit the stud

 

[Skidude17]

I got the shift cables adjusted accordingly, but now the cutout switch is killing the engine at the wrong time. The engine dies when shifting from forward to neutral, and when shifting from neutral to reverse. I did have to raise the lower shift cable pin quite a bit as indicated in the photo, but the roller appears to be in the center position when in neutral and in both gears. I will go through the test procedures discussed in the manual for the cutout switch. Is there anything else I might need to check?

 

[Skidude17]

I got the shift cables adjusted accordingly, but now the cutout switch is killing the engine at the wrong time. The engine dies when shifting from forward to neutral, and when shifting from neutral to reverse. I did have to raise the lower shift cable pin quite a bit as indicated in the photo, but the roller appears to be in the center position when in neutral and in both gears. I will go through the test procedures discussed in the manual for the cutout switch. Is there anything else I might need to check?

I did the test out of the book using a 1/8” Alan wrench since I don’t have the special tool. The cutout switch appears to be in tolerance. What’s my next step?

 

[Bt Doctur]

a bad shift cable will do that

 

[achris]

Try removing the remote shift cable from the shift plate. Start the engine (on muffs) and move the lever to select forward and reverse. Measure the travel to get full engagement of each (it should be the same). If it's 'out of balance', then check the lower shift cable anchor stud is at the bottom of the slot. You could do this without the engine running if you have someone to turn the propeller for you while you move the shift lever.

All this assumes you have pulled the drive and check the slide cavity for dirt, and that the shift cable doesn't have anything inside hindering movement. Seen few with crud inside the slide at the drive end.

Chris.....

 

[Skidude17]

Try removing the remote shift cable from the shift plate. Start the engine (on muffs) and move the lever to select forward and reverse. Measure the travel to get full engagement of each (it should be the same). If it's 'out of balance', then check the lower shift cable anchor stud is at the bottom of the slot. You could do this without the engine running if you have someone to turn the propeller for you while you move the shift lever.


Chris.....

I know the lower shift cable anchor isn’t at the bottom because I couldn’t get reverse to engage without moving it up. I will check the cable for cleanliness to see if that might be causing my problem.

 

[Skidude17]

Try removing the remote shift cable from the shift plate. Start the engine (on muffs) and move the lever to select forward and reverse. Measure the travel to get full engagement of each (it should be the same). If it's 'out of balance', then check the lower shift cable anchor stud is at the bottom of the slot. You could do this without the engine running if you have someone to turn the propeller for you while you move the shift lever.

All this assumes you have pulled the drive and check the slide cavity for dirt, and that the shift cable doesn't have anything inside hindering movement. Seen few with crud inside the slide at the drive end.

Chris.....

I removed the set screw at the end of the shift slide. There was a tiny amount of rust, and I cleaned it off (pic attached).

Do I need to loosen the shift cable retaining nut to inspect further, or is that it for that end?

Should I inspect the engine side as well?

 

[Skidude17]

All this assumes you have pulled the drive and check the slide cavity for dirt,
Chris.....

I need to pay closer attention to what you say Chris. Look at the amount of crud in the slide cavity. Time to put the drive back on and recheck.