Tansom and Motor ????

Well I thought I had a motor located and the deal fell through. I now have to opportunity to purchase another and want to run this past you guys. My boat is a 1984 Tracker Guide V-16 with the following wood transom specs, 1 and7/8" thick, 20" deep and 72" wide. The boat is 15'8" long. The boat was rated for a 35 hp tiller from the factory, but a remote steering system was added later. The motor that is on it now is a 1984 35 hp Merc that weighs in at approximately 148 lbs and has a CMC PT35 with a weight of approximately 26 lbs. The motor that I am looking at is a 2001 Johnson 50 HP with tilt and trim and a weight of approximately 208 lbs. I know that there is a difference in weight and the torque of the 50 has to be much greater than the 35 (just guessing). Can someone tell me #1. Is this to much motor for the boat and #2 how would I build the transom enough to handle it?

I think it wil be too much motor. There is a limit to which you can build up the transom, the rest of the boat has to be able to support the motor also. The back of the boat will sit lower in the water and if you hit some waves it coukd damage the hull.

What does the Capacity Plate (port transom) say is the Max HP?

I'm not positive, but I believe the HP ratings in 1984 were at the crankshaft, not at the propshaft as they are now.

basstender10.6 is likely right. The 50 HP Johnson is probably going to be too much of a good thing -- too much weight aft, too much stress on the boat's structural components, plus you'd need a new steering system -- the cables & pulleys won't do the job.

For the money and hassle involved, I'm not sure the difference in performance is worth it ... just my $0.02 worth.

Good luck.

The plate states 35 Max HP. I do know that in 1983 the motor was badged as a 40, but in 1984 they badged it to a 35. That leads me to believe that the HP rating was changed. I do think that you guys are right about the transom and steering, and will just leave it alone. I love the boat, but hate the motor as it is slow as a snail.

I built up the transom on my boat to support a 40 the boat because it was a short shaft motor before. Short shaft motors are hard to come up with any more, so I was at the marine shop and he was working on a build up of a transom and took some pictures then started in on mine last summer. I have the fab shop weld it as the same time they fabed some of the parts. They strengthen the transoms supports as well. The boat was listed for a max hp of 35, but with the major overhaul and strengthen of the transom. It takes the 40 without any problems. I put pods on the back to counter the additional weight of the 40 as well. I replaced the wood, sandwiched it between 1/8 plates of aluminum with a cap over the top of the transom. The only problem I did not take any pictures of it because it was at the fab shop. I made the first parts of the transom then took it to them for the making of the parts to cap the 1 1/2 of wood and the two aluminum plates. Then I primed and painted it and it looks great.

aclaimsman said:

The plate states 35 Max HP. I do know that in 1983 the motor was badged as a 40, but in 1984 they badged it to a 35. That leads me to believe that the HP rating was changed. I do think that you guys are right about the transom and steering, and will just leave it alone. I love the boat, but hate the motor as it is slow as a snail.

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How are you measuring your boat speed? More importantly, how fast do you want to go?

Is the engine healthy (good compression, regular tuneups, water-separating fuel filters, etc.)?

Do you have a tachometer in the boat? If so, how many rpm will the engine turn at full throttle, trimmed up for speed, with a typical load in the boat? The full throttle rpm should be at or near the engine manufacturer's recommended max rpm.

Rpm too high? Try a propeller with more pitch (1" of pitch=150-200rpm). Rpm too low? Try a prop with less pitch (1" of pitch=150-200rpm).

No tach? Borrow a "tiny-tach" (a very small inductive tachometer) from a marine technician/dealer to get the rpm readings you need.

Something else to consider is boat weight. Find out from Tracker what the boat should weigh, then weigh the boat, and compare your numbers. If your boat is substantially heavier than it ought to be, chances are that the floatation foam under the casting decks, cockpit sole, etc. has absorbed water over the past 27 years.

Locate some of the floatation foam and press down on it -- the foam should deform a bit, but if the floatation material feels "squishy", it's gotta go.

The plywood decks and floor can also become saturated, especially when covered with carpet. In a few inconspicuous areas, use an ice pick or nail to check for water damage to the plywood.

Water weighs about 8lbs per gallon, so a little water here and a bit of water there can quickly add up to a bunch of excess weight.

Just some things that I've encountered in my travels; I could be completely wrong, too.

Good luck.