What does it take to replace TRS drives?
 

I know that if you swap TRS drives for Bravo's you do away with the transmissions, but are there any other drive's such as SSM's that use the transmissions that will bolt right up without major rework of the transom and engine relocation?

Just exploring options/possibilities since I am repowering the boat anyway.

Someone's going to say an SSM II. But they're almost impossible to find parts for and your X dimension will be at least 2" too low if you just bolt it on.
III, IV, and V's use pretty much the same gimbal (different from TRS). This requires glassing transom, recut, new tranny tailstock, external hydraulic steering.
Same is true for VI.
Stick with the TRS if you're under 550hp.
My $0.02
Gary

You could go with the Pulse Drives and have a surface drive and the cool rooster tail! :D

Hey Monty,
Here's another thing you need to talk with Mark (KAAMA) about. He did that too!
http://www.offshoreonly.com/forums/s...avo+conversionswap thread
DS

Madhatter's dad is running over 700 horsepower through his TRS drives with very good luck. I understand he had his transmissions upgraded by Huber.

I tell ya, I've heard the whole gamut of opinions regarding the TRS's. Some people don't think they're capable of handling anything over 450hp or so, then you've got other's giving examples of them living reliably behind big power. I've got plenty of room, prbably 3-4' infornt of the engine's, so the space benefits of going to Bravo's and eliminating the tranny's don't really concern me. I guess it would be nice to take a little dead weight off the boat, but I doubt it would make a significant improvement in performance.

The 540's I'm building will make around 665 ft lbs and 575 hp. I don't drive my boats that hard - easy out of the hole and do my best to keep the boat in the water (my wife wants a Formula PC, so it's self serving to make the ride as smooth and comfortable as possible). However, I would like to be able to comfortably hang with most of the other boats on Lake Michigan without beating on the engines and reving the hell out of them.

Too Old had the drives rebuilt by Doller Offshore and he says there's roughly 0 hours on them. Not surprising I guess since it sounds like he never gets his boats wet, LOL. I was planning on having the tranny's rebuilt/freshened up anyway since they appear to be stock, originals. I just want to make sure I'm not replacing or fixing drives on a regular basis.

FYI,
Merc used to offer a 575hp, 540 cid tall deck motor with TRS drives and standard B/W Velvet drive trannys.
You'll be fine.
Gary

Monty,

There is a guy in Granger, Indiana that rebuilt the TRS and done some of the conversions. His name is Chris Merrill give him a call at 574-272-0618. Nice guy and will discuss his problems he had. Good luck, it is a nice looking Boat !

Monty,
Years ago we ran 540's through TRS's no problem, today they seem to barely hold up to 500 HP. I have heard that the factory changed vendors on the gears a while back. If you want to really be able to run the boat without babying it I think you are asking for trouble.

Gary, if my memory is correct the 575 was sold with SSM drives, if you look at the parts breakdown for the trans it shows the SSM tailstock. Also, the trans had an extra clutch plate in it.

I switched from TRS to Bravo One XR's with Stelling extension boxes. I found a pretty good deal here on OSO with a guy who was taking all his new Bravo One drives off from his new 2000 boat that had the Merc HP500 engine packages and was upgrading his boat with #5 SSM's. His drives/transom assemblies only had 20 hours on them when he was making the switch, so I bought the entire drive and transom assembly package from him which is what I needed to make the conversion. While I was making this conversion I decided to go with the Stellings extension boxes and new Merc Bravo XR drives. I sold the other Bravo One HP drives that I bought as a used package and sold off my TRS drives/transom assemblies and transmissions which helped in funding the conversion project.

I wanted extension boxes on my boat and there weren't any available for the TRS drives and because TRS's were quickly becoming a thing of the past I knew that most likely no manufacturer would produce a TRS extension box. Plus TRS parts are becoming more and more out-dated, not as readily available and thus replacement parts would be more costly. So for the price I was getting for the Bravo One drive and transom assemblies with only 20 hours on them I thought it was a no brainer for the most part and now I have more of an updated boat. :)

I take it you also had to fill and rework your transom then?

Monty, yes that had to be done on my boat, BUT there is a easier and less costly way now. Stelling's now makes a TRS to Bravo conversion that is all done within their extension box. The extension box on the transom side has a TRS bolt pattern so that it will bolt right up to the existing TRS bolt holes that you now have in your transom, HOWEVER on the drive end of the extension box it has a bolt pattern for a Bravo One drive thus eliminating the need for having to fill in and recut the transom of your boat! I guess the only draw back is that you have to buy the extension box which STILL is an expense, but there is much less labor involved. :)

Fred,

Yeah, you mentioned to me how much you paid Doller to rebuild them, that's one of the main reasons I'm hesitant to replace them. I haven't made a decision yet about what I'm going to do - stay with the TRS's or switch to something else. It just seems like everyone has a different opinion about them. As I mentioned earlier, for everyone who says they're as weak as a wet noodle, someone else comes up with an example of them living reliably behind big power.

My main goal is just to have something that will be reliable behind the 540's I'm building without me having to spend more on a pair of drives than I paid you for the boat. The thought of redoing the transom is unappealing due to the very good consition of the hull.

When you had them rebuilt, were they "upgraded" in anyway, or were they just rebuilt to stock specifications?

I'm gonna have the tranny's redone since they appear to be stock originals. Might as well since I have them out. I'll have extra clutches and steels installed to increase their torque capacity.

Cool, Thanks as always Fred.

TRS
 

Hi Monty, These is no upgrade for TRS drives, and we have found the stock parts to be getting more and more scarce. As you would read in the Bravo XR, XZ post, the life expectancy has alot to do with the method of running the boat, as well as HP and weight of boat.
If you would like to discuss this further with our Sterndrive tech, John Klumpjan, please phone him at 800-376-1616, or 954-463-9988. Or for the conversion info, ask for Mac.
Regards, Mindi

I am surprised no one mentioned these:

Konrad Marine Drives

Anyone ever use them? Supposedly rated to 800hp, bolt up to TRS, 2-speed trans...

Has anyone on the board ever used a Konrad drive?

Spectra32,

I looked at their site, but I didn't see any mention of it bolted right up in place of a TRS?

"Transom Mounting Template available, patterned after popular mount." patterned after popular mount. You need to call Konrad, but I'm certain this popular mount is the TRS.

Monty,

You can always put Bravo's on your boat, they will be around for ever. The TRS is a tough drive, the weakest link is the lower gears. I inspected and replaced my lower gears this spring after 300hrs of hard use. I run a 311 with ZZ502's(567ft lbs), and I'm not easy on it.
While BAM seems to be anti TRS, and Doller seems to be neutral, there is a place called Offshore Performance Specialties(Don Carter)who is definitely pro TRS(offshoreperformance.com), and stocks alot of TRS drives and parts. Since your drives are fresh, I think I would save all that dough and buy my wife something nice.

Lake Effect,

Thanks for the info. I have seen Offshore Performance's ads in Powerboat, I'll have to check them out. I also found out that Bravomax has a TRS to Bravo conversion kit for $9100 that includes a rebuilt Bravo and everything needed to convert - except the transom glass work. It's too bad the Stellings TRS to bravo conversion box doesn't work out right. You'd think with the thousands of TRS drives still out there, there'd be enough market for someone to build one right.

I've pretty much decided to stick with the TRS's this year. I'll run the 540's for a season and see how everything holds up.

I think you will be fine. I would not bother to go through all that work to convert to Bravo drives. I am not very impressed with them. Speedy III`s would be worth the effort.

Good luck with your Mistress :D Got to see it at Too Olds last spring, she`s a real clean rig.

Here`s what I`m running through TRS drives. I`m satisfied with them.

I'm surprised that no one has come out with a bell housing that would adapt a TRS gimbal to Bravo upper. Now that some aftermarket manufacturers are going back to sing trannys, a package with a bell housing and stronger non-shifting bravo upper would be pretty appealing.
You would also eliminate all the weak parts of the bravo setup; gimbal, upper, and coupler.
Gary

Biggus,

That is a sweet looking setup you've got. Wow!

If I were to replace the drives, the IIIA's would be my first choice as well.

I'm a decent fabricator and have thought about trying to make my own extension box which would adapt either a IIIA or a Bravo derivative to the TRS gimble. Nothin that couldn't be made from tig welded aluminum plate. I know a couple of people with CNC's that could easily machine the adapter plates if I give them a template. I could then "box" the adapter plates with aluminum plate.

had craig collabella build my trs drive and talked about differances between trs and bravo. told me trs is stronger than a bravo. if you would upgrade i would go to #3 before a bravo. my .02. eric....