Bad News

Michael T

Steve, this is just fun....I thought you had a thick skin!.....you have a diesel - for goodness sake you have to be able to take a hit! LOL

Handymans342

Well how long would it take to overheat? You said rest every hour so that means running at cruising speed over 1 hour and the drives overheat? 

Handymans342

Maybe I should reroute my exhaust. 

Handymans342

Does that mean my drives are out of the water at plane? Isn't exhaust hotter with diesels? 

Michael T

I used a multi point drive shower on the Bravo 1 that was driven by a 390 HP engine. That drive was fully out of the water at higher RPMs. The top of the drive went from baked-on lime like deposits to shiny  OEM black as soon as the drive shower was installed. Installing the drive shower took 40 minutes and I was ocd careful.

Steps: dry fit drive shower, mark where hole will be drilled through the anti cavitation plate to allow the drive's water pick-up to pass through, loosen and remove two bolts on drive cap to install the drive shower tube support flanges, re-torque drive cap nuts to spec. Done.

I had a friend video the shower in action and the water was blasting all over the top 2/3s  of the drive. That was over 15 years ago. Drive is still fine.

Handymans342

They make some now where no holes are drilled. MT, is your drive out of the water on ur 360. Don't know how you see this

Michael T

The drive on my 360 is definitely out of the water but there have been no signs of heating as evidenced by deposits. Deposits form very quickly on a drive tower that is IMO too hot. I believe that the Blll X drives are much more robust and cool better.

I like the drive showers  with the hole through the anti cavitation plate as that puts the SS tube right in clear water for maximum volume.

I have installed double showers for friends that are essentially a U shaped shower with two water pick -up but those were for high performance applications that generated a LOT of heat.

From what you have said I would probably use a two pick-up drive shower for each of your drives.

I saw the performance of the SS  drive shower on my Bravi l because my friend followed along and videoed it.

I know my 360 drive is out of the water 3 ways, pure measurement, having seen videos of 360s on plane and having followed another 360 while it was on plane.

Handymans342

On my boat they sit so low. Hard to imagine they are out of water but from what AL said you can't drive over an hour without the drive overheating. 

Michael T

That is so far past ridiculous that I would come up with a solution.  Seriously, I'm nor being rude but what the h*ll is the point of having a cruising boat that can only run on plane for an hour. WHAT???

Handymans342

Just another downside of drives

Michael T

Steve, I've never heard of that before with any drives. I could run at 3400 rpm all day if I wanted to. This has to be a diesel issue - which begs two questions:

1. Why would anyone buy a diesel with stern drives

2. Why, after all this time, are you just finding this out? For years you have been saying that your diesel 342 can out cruise the gassers due to mileage capability but now you can only run it for an hour then wait for it to cool down. I could run at 32 mph for 8 hours with fuel to spare and I'd have gone 256 miles. Where would you be?

This has to be an April Fool's joke right? Seriously, this can't possibly make sense.

TonyWalker

Yes, there just has to be an abnormal root cause in there somewhere.  I can't believe that the drives would react differently to the fuel that runs the engines that power them.

Michael T

....and even if diesel fuel burned hotter for some obscure reason like higher compression in the cylinders does anyone want to guess how hot the gas coming from all of the new catalysed marine engines is?  If Steve's not "pulling our legs" something is definitely off!

Handymans342

It's just what AL said guys!!!! Geez

TonyWalker

Still thinking on this one.  Diesels turn slower that gassers I think.   So the gearing in the drives maybe should be different for each type of engine.  So among the consequences, there might be just not enough cooling water.  Pump in the drives maybe different?  If so, could it be that you have pumps in the drives designed for gassers and not Diesels?  

Handymans342

And yes diesel exhaust is a lot hotter but remember that cooling water is mixed in with that. Guess we need temp gauges on our drives now so we know when to come off plane. See what you started now AL? You probably just bought a drive shower company LOL

TonyWalker

I have never had to consider run times dictated by temps in the drives.  Never been suggested to me by anyone anywhere that this might be a necessary consideration.

Handymans342

Just what AL recommended Tony

Michael T

I could not run oil temperature tests of the Bravo l that I put the drive shower on but before I did if I put it right onto the boat lift and felt the drive tower top after a fast run I would have burned my hand.

After the installation of the drive shower the drive tower top was cool to the touch no matter what. For the cost (inexpensive) I'd get showers.

NOTE: if you buy a solid tube shower make sure it has enough clearance to fit under your swim platform. Dumb and Dumber (my friend and I) installed one that he bent when he trimmed up the first time right after we installed it.

 We re-did the job using a flexible SS braided drive shower hose that worked great. Unfortunately, the two Admirals witnessed the whole scr*w-up and still like to tell that story even though it was more than a decade ago! It just hangs around us like a dead dog.

Handymans342

I have no pump in my drives

TonyWalker

And another difference is that I have Volvo engines with the OceanX drives.  A total repower a few years back for Salt Shaker as many on the forum know.  Great power package for a gas 342.

Handymans342

Makes you eat more fuel Tony

LaRea

What Al said is that your drives and oil will stay cooler if you come down off plan every now and then.  Guys, that's not the same as saying "you can't drive longer than an hour."  

TonyWalker

Believe it or not, I think it is less fuel with the new power as indicated by my fuel flow metering system.  Just by memory, 24 gph-total for both engines,  3700 rpm, typically 24-25 mph.  I think the fuel burn was not quite that good with the original power and drives.

Handymans342

Tony, you better do 30 mph the whole way to the keys

TonyWalker

Easy enough!  lol

frodo13056

A few years ago, on the old Rinker forum, there was a ton of discussions on how hot the Mercruiser drives can get while on plane since they are out of the water. I organized a "group buy" of drive showers from Simrek for the bolt on drive showers and we got the bulk purchase cost of I believe about $125.00 per shower since the group purchased something like 30 of the drive showers. Simrek now offers a bulk price which they did not have back when we did the group buy. The first time I went across Lake Michigan and back (about 180 miles) when I drained the lower unit gear lube at the end of that season, it was pretty discolored and very smelly. That off-season, I added the drive showers and have never had any discoloration of the gear lube at all with multiple long trips during the season. Just an FYI - Mercury Marine used to have a statement on their Mercruiser page that expressly voided any corossion claims on drives that had been drilled for some brands of drive showers - which is why I wanted the bolt on type. Now, I would not own a stern drive without a drive shower.

Handymans342

Well I am going to install 2  www.driveshowers.com  No holes.

summerx

they changed the design a few years back, from the old drill through the cavitation plate to the current style which gets connected to the fasteners holding the hydraulic cylinders to the end of the cavitation plate.  Water pick up is still below the plate in clean water.  Have the new style on my rinker, and the old style on my last crownline.

randy56

good move handy