Transom Saver ROD or BLOCK???????

[zacsrib]

Greetings RIBS & SIBS...
I'm new to the forum and looking forward to learning and sharing.
My question is others experience with "transom savers". I see (2) basic types one is a spring loaded rod that connects to the trailer frame and the other to the lower end of the outboard and the other is a block of hard rubber about 6" (15.24 CM) that fits on the trim-tilt (TT) shaft where the (TT) is lowered to make the rubber black snug to stop any bouncing of the outboard. At least that my understanding of what or how the rubber block is supposed to works.

I'm planning on doing some traveling with a 5M rib with 75HP 4-stroke and concerned I apply the right product.

Like to know plus and minus of each.

[Limecc]

Welcome!

I wasn't worried about the transom as much as the flimsy tilt lock engine bracket. I made my own out of 316 stainless for just a few quid.

I also used a 25mm ratchet strap to hold the engine in full lock.

I wouldn't want to connect engine to trailer in case the boat moves or settles. Bad idea imho.

[zacsrib]

Nice work I like that. Yours is similar to the rubber block method but I think better . The block compresses on to the trim/tilt and I don't like that applied force on the ram cap. Its one-way and that's all there is. I'm still trying to process the "transom savers" use. The boat does need to be secure to the trailer and the TS connected to the trailer and outboard. If its not connected you do have a swinging weight transferring dynamic energy to the transom no matter how light with road vibration or depending on impact or recoil of hitting a pot hole the energy swing will be greater so the TS reduces those extremes getting transmitted to the transom. I have a similar reservation on the trailer to outboard because there's really not much of a suspension to the trailer so if the boat is braced to the trailer it transmits everthing ....I would like to see a real engineering point of view from the Mfg'er rather than the "I've used it for years" that I see on YouTube. Thanks for sharing!!

[Limecc]

Thank you. The best thing I did for the transom was to replace the old suspension which had sagged and lost travel, the rubber cords had hardened. Also upgraded it from 750kg to 1000kg so it's not working so hard. Boat rides much smoother now. No shock loading.

Cost unlimited, the next idea would be using soft rollers like this:

[harrison]

I would like to see a real engineering point of view from the Mfg'er rather than the "I've used it for years"

Unfortunately, unlike in the US/OZ, not many over here in the UK seem to use transom savers at all. Even less on here as essentially a blow up boat group with very few trailered rigs.

On our 5m/60hp rib, which is generally only towed very short distances, then just utilise the tilt lock lever. If towing long distances then we lower the motor onto a timber block trapped between saddle and leg to take the strain off the hydraulic tilt.

On our 3.4/20hp mini rib, which regularly does 400+ mile road trips, then we cobbled together a diy rigid transom saver as very difficult to buy commercially over here. No power trim/tilt on our 20 so the saver protects the flimsy tilt mechanisms.

Neither of our solutions is to primarily limit shock loads on transom (although they do) it’s more to protect the trim mechanisms from excessive live shock loads.

Of the two the rigid transom saver is by far the best solution for the manual tilt motor. From an engineering point of view it’s a simple pin jointed triangle of forces. Very strong/efficient and can accommodate slight movement of boat on trailer (not that it usually happens) as the angles would just change to compensate without additional loading to any individual component.

Home ‘brew’ transom saver

[Limecc]

My main concern differs slightly to @harrison in that I'm not that worried about the trim/tilt mechanism being overstressed because there's a tilt lock.

On my Merc 30, this was a double affair and quite substantial. After fixing the leg from upward and lock to lock movement with a ratchet strap I'd be happy to tow it anywhere, any distance.

Fast forward a few months and the Merc 40 was an entirely different beast. A one-sided flimsy tilt lock, it really needed the brace I made because of the weight, and this protected the ram better than the Heath Robinson bit of wood that many use. Again not worried about bursting hydraulic seals or bending the piston rod, but a real concern about fore/aft twisting forces remaining on the transom. I noticed vertical cracks in the gelcoat on each side of the transom. Not entirely sure they weren't there before and I didn't have the boat long enough to see if they developed, but definitely a worry and not helped by loading to the max design weight for the transom. Neither helped by knackered and hardened suspension. With the car window down I could hear rattles and bangs over potholes, not good for the hull or transom, I guess these were caused by the roller carriages.

On a side note, I find it odd that roller trailers are not more common in the US. The weight might be better distributed on bunks but in the UK this is done with more rollers or roller bunks and it's possible to launch with far less depth of water. Indeed it's possible to dry launch onto grass or sand if ever trailer maintenance was needed.

[zacsrib]

Harrison & Limecc. Nice works guys I wish we were neighbors....

The opinion on rollers is hull damage vs bunkers. I agree on ease with rollers on beach launch on day trips where tide has gone out and I have to back pretty far out to recover.