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cvx
03-07-2009, 08:34 AM
Asked this ? on OSO, but there are probably more of them here, so how many rpm do ya dare run through an SS? Turning 5500 now w/ no problems. Thanks

Donziweasel
03-07-2009, 08:36 AM
Dunno, but if you are going to run that many rpm's through it, I would get a drive shower to keep the upper cool......;)

Parts for SS are getting harder to find.....

cvx
03-07-2009, 09:00 AM
Yea,I do have a spare just in case. I'm running a wingplate shower, reason for ? there was a guy runnin' 5900-6000 thru his, thought that was a bit much.

BigGrizzly
03-07-2009, 09:18 AM
This question has a two fold answer. First is the power that is applied and also the Rpms. If you run just under 6,000for short bursts it may not be an issue. They really don't like high rpms for long. What needs to happen is if you run high rpms then the prop needs to be small to take the load off the drive. The problem is you may go faster with a bigger prop at less Rpms. There is no free lunch. The final real answer as told to me by a Merc guy, RPMs hurt, the drive more then the motor. The drive was designed for 300 HP at 5500 rpms. take it from there. There is always some exception somewhere.

Lenny
03-07-2009, 09:30 AM
I run mine at 5100.

fogducker III
03-07-2009, 09:58 AM
I run mine at 5100.


When....?????:umbrella:;):jestera:

cvx
03-07-2009, 10:01 AM
Thanks Grizz, I PMed you about a week ago on the TXP vs Mirage vs Lazer2. If I run the smaller diameter Lazer at higher R's, can I get by with it for short bursts like you said above. I have noticed a bit of shadowing on the top bearing in the upper after 2 years of use, maybe 25-30 hours.

cvx
03-07-2009, 10:12 AM
Yep, also went with the Gen 2 gears.

BigGrizzly
03-07-2009, 10:21 AM
I remember, It is not just the bearing it is teeth chatter on gears. I would probably get a higher viscosity synthetic gear lub with a higher shear strength too. Just try to avoid slam dunging the throttel and quick on and offs.

cvx
03-07-2009, 10:29 AM
Yeah, I always take off and slow down gradually, don't want Alpha Bits. I'm running Mercruiser High Performance Gear Lube Plus, is there one better suited?

BigGrizzly
03-07-2009, 10:40 AM
There is always one better, there is a gold one just need to change it more. Also Amsoil and Royal purple. BTW the HP merc stuff is also a synthetic

Sam
03-07-2009, 07:45 PM
I run mine between 5000 and 5200 and have always used a drive shower, I've yet to have any gear issues. I use the Merc HP drive lube which is a semi synthetic lube not a true synthetic. I know Doug Lovins runs his around 5700 rpm plus and has never had a failure other than when he bumped bottom :banghead:, he also uses the Merc HP.
The only thing you have to watch out for is the low water pick up has a tendency to suck weeds if you happen to get caught in a thick patch. In which case your going to get hot very quick :eek:. Once you get towed back you can pick out the weed via the side access ports on the drive, then flush and your good to go.

cvx
03-07-2009, 11:25 PM
Yeah, ran into that issue couple years ago when I tore the engine down, lot of sand in the block and exhaust man. Installed an inexpensive strainer and water psi gauge to monitor. I was looking into Lucas Oil 85/140 syn. gear lube.

BigGrizzly
03-08-2009, 08:47 AM
I can say that Merc HP is one of the best, A known good thing in outdrives. Unfortunately, no one has ever really tested-lab tested that is. Now the car guys, off road guy and the like have their favorites too. The next thing is the corrosion resistance and water intrusion thing. Truth is all good ones have the same stuff because the differentials have breathers. As for Merc being a synthetic, it is, not a full one, but only performance counts, not what it is made of. The merc clearly works. Heck if olive oil was better I would use it.

cvx
03-08-2009, 03:10 PM
So, just to recap, if I go with a full synthetic, step up to 85/140 or stick with the 75/90 lube?

osur866
03-08-2009, 03:30 PM
So, just to recap, if I go with a full synthetic, step up to 85/140 or stick with the 75/90 lube?
I think to reacp, is to use the merc Hi-po with drive shower and change often. Thats what I do, I don't have an SS, but change the drive fluid every 25 hrs. along with the engine oil both at the same time. Just my .02

BigGrizzly
03-08-2009, 05:37 PM
If your running hot the 145 is a better option, but no guarantees.

CHACHI
03-08-2009, 06:24 PM
I The only thing you have to watch out for is the low water pick up has a tendency to suck weeds

A tendency? I thought the SS's job was to help keep the bottom of the bay free of weeds around my boathouse.

Ken

Sam
03-08-2009, 07:24 PM
A tendency? I thought the SS's job was to help keep the bottom of the bay free of weeds around my boathouse.

Ken

There's one :jestera:in every crowd.

Sam ;)

smokediver
03-08-2009, 07:29 PM
I use the hp merc. stuff . there was a test done by the scream and fly guys who used a product made by alyson .. spelling ? anyway , it has the viscosity of water just about and they picked up a few mph testing it . they tore down the lower unit and it was fine .. no problems ... i wouldnt use it but ... just passing along info ...:D

BigGrizzly
03-09-2009, 07:39 AM
Minx guy cool a 300HP weed wacker. Smoke, the problem with tests is I really doubt they got that extra speed. Conditions day, temp etc. True thinner is faster, but too it takes the cushion out of it. I am sure that you will agree that Lower unit vs 1 to 2 Mph, is not a good trade off. Go with what you know has a good history in the application. I looked up Royal purple up, and talked to some serious racers of cars. Seems to be great stuff, but twice the price. As for Amsoil, Honda has tested most of their stuff, It is one of the best if not the best in lab and real conditions. Both in cars and marine. Not trying to get anyone to change just information. The Konrad comes with Royal Purple, so I will keep using it.

cvx
03-09-2009, 09:39 AM
Well, I do have access to both Royal Purple and Amzoil locally, now all I have to do is make a choice. The amount used in a drive won't break me, so cost really not an issue. What about an external resevoir tank for pressure build up?

PlumCrazy
03-10-2009, 01:05 PM
Asked this ? on OSO, but there are probably more of them here, so how many rpm do ya dare run through an SS? Turning 5500 now w/ no problems. Thanks

The SS on my old 19' Baja ran 6000 RPM normally and up to 6500 RPM on a 125HP shot of nitrous for several years. I had a mechanic go through it just as a precaution and he said it all looked perfect. I did run a Simrek drive shower.

PlumCrazy
03-10-2009, 01:11 PM
A tendency? I thought the SS's job was to help keep the bottom of the bay free of weeds around my boathouse.

Ken

Put a small dowel pin through the drive at the front of the intakes. This will help keep the weeds out.

CHACHI
03-10-2009, 01:33 PM
Put a small dowel pin through the drive at the front of the intakes. This will help keep the weeds out.
Thanks, but I sold the drive. There was no gain on my Minx.

Ken

Sam
03-10-2009, 03:45 PM
Put a small dowel pin through the drive at the front of the intakes. This will help keep the weeds out.

I have sort of bra like devise I made up that works pretty good. The only downfall is that you need to hang off the back :eek:to take off and on while in deep water.......no biggy.

cvx
03-10-2009, 04:54 PM
Yeah, but can you remove it with one hand?:smileybo::jestera:

Rootsy
03-11-2009, 09:04 AM
Used to spin mine 5800 +/-... Merc Hi-Perf gear oil... Drive shower is a good investment.

cvx
03-11-2009, 07:36 PM
Hey Rootsy, bought those 2 drives you had listed for a guy from NH about 2 1/2 years ago, 1 was in pieces. Had em both rebuilt, work great. Thanks for the connection. :beer:

smokediver
03-12-2009, 07:13 AM
here is the link from the scream and fly test . I hear you big griz , i only run merc hp ...http://www.screamandfly.com/home/evaluations/alisyn_longterm_test/1.htm