Aquamatic Swap

I've run a 260A with a 250 drive. I have a complete 280 V8 ratio drive. The only thing I've checked so far is that the helmet bolts are the same. What other problems might I run into with the swap.

I did that exact drive swap. As I recall it was uneventful. I did however, change the water inlet to thru hull with an external wedge/scoop strainer ( does not need cleaning). This eliminates the water elbow of the drive which is a "wear item" and as I had it set up, provides a flusher/winterizing "t" at the shutoff valve inside the hull. I eventually went thru hull with fiberglass mufflers with the exhaust which got me an immediate 450 RPM increase in engine speed at WOT.

Change the plastic bushings on the pins, and grease the pins when you replace them.
If you are reusing the pins, take a file and break off any rounding (mushrooming) of the ends very carefully.
The ends of the "latch hooks" are a wear point and if worn will result in failure of the drive to latch down in reverse...

jeffnick said:

I've run a 260A with a 250 drive. I have a complete 280 V8 ratio drive. The only thing I've checked so far is that the helmet bolts are the same. What other problems might I run into with the swap.

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First verify that you indeed have a 250, and not a 200.

If you make this swap, I would suggest using all of the 280 components, i.e., transmission, Intermediate housing, lower gear unit and the 280 suspension fork.

The 250 transmission is the small bearing unit, which means that the 250 and 280 transmissions cannot be interchanged.

The 250 suspension fork has inserts in each side, which makes this fork not as stout as the 280 suspension fork.

The 250 collar steering fork shaft is of the small diameter. These go through bushings rather quickly.
This would be a great time to install new bushings for that.

When you go to remove the suspension fork "hinge pins", use heat to warm up the aluminum boss areas. Propane or Mapp..... NO Oxy-Acet!!!!
Heat will slightly expand the aluminum, giving you a better chance at removal.

DO NOT drive against these soft pins with anything harder than an Italian Bread Stick.
If you use a steel punch, you risk expanding the pins, making it even more difficult to get them out!
Drive on these with aluminum or brass ONLY!


Also, take heed to what Bob suggested re; new bushings and taking off any burrs etc. prior to re-assembly.



Have you replaced your PDS bearings?




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Re Hinge pins... On a used boat once, the pins had been driven by the P/O and were slightly peened over. After much creative language, I did the following:
Disconnected the helmet and everything else.
Swiveled the drive to the extreme (left or right) and using a long wooden dowel I drove the pins from the inside to the outside. Be sure to VERY slightly lift up on the drive ( while its latched to the transom shield) to take the vertical loading off the pins. Repeat for the other side.

Thanks guys. Now for some decent weather to inspire me to get started.

Heat is always your friend regarding something like suspension fork hinge pin removal.




If the hinge pins show any signs of previous flaring damage, you can true them like shown below.
Use a very fine sanding disc, and just gently roll them against the spinning disc.

...... just VERY gently...... You want to polish more than remove any material ( except any mushrooming)
If they are banged up and or corroded... buy new.