Lower Unit Removal

[Ckingnirvana]

I recently picked up a 1998 DF 40 that has seen little use (less than 50 hours) and has been sitting for about 10 years. I got the motor running perfectly but wanted to replace the impeller as a precaution. However, I cannot get the lower unit to separate. I removed the six bolts and linkage turnbuckle, checked under the trim tab for hidden bolts, and have tried to pry the lower unit loose with a combination of putty knives and wooden shims. While I have some separation of about 1/2 inch, I cannot get any more separation. I am afraid that the splines on the shaft may have fused with the bearing seat at the fly wheel end. I sprayed a considerable amount of penetrating solvent but am not getting any closer to removing the lower unit. It definitely seems as though it is stuck at the top near the fly wheel.

Is there any other way of freeing the main drive shaft by either removing the fly wheel or mid-unit?

I am wondering if I should invert the motor so that the penetrating solvent can run down the shaft to the problem area.

I am reluctant to sea trial the engine until I get the impeller replaced even though there is a good stream coming out of the pee-outlet.

Any suggestions would be greatly appreciated.

[WEDOCQ]

There is usually a hidden bolt. Ugh, cant think of the name, but it's underneath the directional thingy that's toward the front. Lol, now that's some techy info there.
-Shawn

Trim tab zinc anode. underneath that. ha

[Ckingnirvana]

Lower Unit

It's called a trim tab/zinc anode. They started using the extra hidden bolts on the DF60/DF70's I believe. Besides I already removed the trim tab and checked earlier. No hidden bolt.

Thank you for the suggestion though.

[Solarman]

Is it hanging on the shaft side or the prop side?
It isn't impossible for a hidden bolt, but if you're certain there are none, then the only thing on prop side would be the guide pins frozen in place, lube as good as you can, then using a soft piece of wood with a rag under pound on the tail section just below the seam to help dislodge.might help to work putty knifes as you go.
If the shaft side is the problem, then the same procedure, but do NOT hammer on the plates/ fins. Also, as you wedge the putty knifes in (there are guide pins this side too) also rotate the flywheel by hand slowly (it may help to remove the plugs for this step.) It is very difficult to dislodge the drive shaft if frozen in place, but persistence will win. But make sure you use putty knifes on both sides evenly at same time to give equal pressure, wether prop or shaft side. Be careful, it is only aluminum, and if hit too hard may break, that's why the putty knifes are extremely helpful.
Good luck, and make sure you use a heavy grease on the (cleaned) shaft splines when it goes back together.
Just remember patience, and working each tool a little each will work best.
Let us know how you're doing.

[Harper2]

First.... did they make a DF40 in '98? In any case, you say you have about ½" separation already.... is that ½" all the way around or just on one end? It's pretty sure that you have all the bolts, else you wouldn't have that much separation. I would try wiggling it (rocking) gently, without too much pulling force until it felt like it was starting to loosen a bit. and continue with the penetrating fluid soak. If it feels like the hang up is around the center of the unit, it might be corrosion/rust on the drive shaft splines. If you get it separated more with the rocking, and can fit a board in between the middle and lower unit, then you can start to gently tap with a dead blow hammer, alternating sides as you go.

[Solarman]

well heck Mike

If you can get it 3/4” open, you can put two boards across from each other and prys it on down. Lol. Yes, rocking it can help Mike.
And, it is most likely old dried up grease that tends to act more like glue from lack of movement.
Any way good luck, i've been on your end, and it isn't fun.

[Ckingnirvana]

Lower Unit

Thank you so much for the response. I thought that Suzuki didn't start making the DF40's until 1999 but the id plate says 1998. I have about 1/2" all the way around the lower unit. The pins don't show any corrosion so I am guessing the problem is the drive shaft is not disengaging due to corrosion on the splines. I am wondering if I should invert the motor so that the penetrating solvent can run down the shaft to the problem area.

The motor ran great after I rebuilt the vapor separator, replaced the fuel lines and cleaned the fuel pumps. I couldn't see running the motor until the impeller failed though. I really believe in doing preventive maintenance to avoid more costly problems.

Thanks again for everyone's input.

[Solarman]

Sorry Cking, should have read what you wrote closer.
Removal of flywheel won't help, and removal of powerhead will also be extremely more difficult with shaft stuck.
Inverting motor would be good to get penetrating lube down to splines, but nothing that might damage crank seal. Heating the driveshaft in the upright position (heart rises) could help greatly if it is old dried grease? But the space seems too small to do that if only 1/2” at this point.
Think you're better off using the shims and putty knives at this point. Combine the wedges & putty knives with hammering on the end of 2x4 block seems best approach still.
You could use large screw drivers in between putty knives on both sides if you have enough help/ hands.
Steady pressure spreading the sections apart while hitting block of wood around where able, or safe to help dislodge by shock is what i've had to do in past.
The ”jaws of life” that Fire depts use would be ideal here, one on each side and you'd be done quickly. Ha ha.
Turning the flywheel by hand will help, as the steady pressure of wedges, and hammering on the block allows the shock to work around drive shaft evenly.
If it does loosen, it might drop all at once, or little bit at a time.

Good luck.