stern drives...

[oldfielder]

Pelican-
I suggested the flusher for the bravo because my boat has the same cooling setup and with the boAt on a trailer i now have a good system to run it in the driveway.
I agree about the block flushing not accomplishing much.
I've been down the manifold failure route-aint no fun. Was able to save the motor though with some quick action.

[Blue_Heron]

Originally Posted by oldfielder

I suggested the flusher for the bravo because my boat has the same cooling setup and with the boAt on a trailer i now have a good system to run it in the driveway.

My 350 Mag MPI has closed cooling (including the manifolds) and came from the factory with a quick disconnect for running it on the hose.

Pelican
What is the most common cause of water ingestion, manifold failure? Do the manifolds rust out from the water jacket side, or from the exhaust passage side? Or is it riser gasket failure?

Dave

[pelican]

Originally Posted by Blue_Heron

My 350 Mag MPI has closed cooling (including the manifolds) and came from the factory with a quick disconnect for running it on the hose.

Pelican
What is the most common cause of water ingestion, manifold failure? Do the manifolds rust out from the water jacket side, or from the exhaust passage side? Or is it riser gasket failure?

Dave

i think you might wanna check that cooling system again - i don't think merc manifolds are freshwater cooled.

the cooling passages will erode - the gasket surfaces erode too - mercs are not as prone to this,later model mercs - they use a "dry joint" system...

those MPI'S with the horizon package - like the one you have,is it new as in 2011 ? if so,it would be equipped with catalytic converters - to pass the emissions standard ...your engine cat equipped ?

[hiliner222]

Originally Posted by pelican

i think you might wanna check that cooling system again - i don't think merc manifolds are freshwater cooled.

the cooling passages will erode - the gasket surfaces erode too - mercs are not as prone to this,later model mercs - they use a "dry joint" system...

those MPI'S with the horizon package - like the one you have,is it new as in 2011 ? if so,it would be equipped with catalytic converters - to pass the emissions standard ...your engine cat equipped ?

There is a closed cooling system and a half system. The half system flows fresh water through the engine only the full system does the manifolds also with block off gaskets at the risers. On a full system salt or raw water only passes through the risers and out the exhaust. You can plmb the mercruisers either way.

[oldfielder]

That's a sweet setup. I'm jealous.
It seems like the only issue you will have will be keeping an eye on the risers.
Does that motor turn 325 horses?

[Blue_Heron]

Originally Posted by pelican

i think you might wanna check that cooling system again - i don't think merc manifolds are freshwater cooled.

I think the closed cooled models may have been available with cold manifolds or warm manifolds in different years. Check out the back of Mercruiser MPI Service Manual #31, you'll find water flow diagrams for engines with the manifolds cooled by the closed system. I vaguely remember verifying mine was piped like that, but I haven't looked in a while. It's sitting in my shop covered with a tarp.

Originally Posted by pelican

those MPI'S with the horizon package - like the one you have,is it new as in 2011 ? if so,it would be equipped with catalytic converters - to pass the emissions standard ...your engine cat equipped ?

Mine is a post-Horizon, Seacore model but not a 2011. I bought it last year. No Cadillac converter.

Originally Posted by oldfielder

That's a sweet setup. I'm jealous.
It seems like the only issue you will have will be keeping an eye on the risers.
Does that motor turn 325 horses?

Nope, just 300 ponies. I think the only 5.7 engines direct from Mercruiser turning 325 HP are carbureted. I was considering one of those strokers like Island Trader got, but couldn't find one with closed cooling.

Dave

[pelican]

Originally Posted by Blue_Heron

I think the closed cooled models may have been available with cold manifolds or warm manifolds in different years. Check out the back of Mercruiser MPI Service Manual #31, you'll find water flow diagrams for engines with the manifolds cooled by the closed system. I vaguely remember verifying mine was piped like that, but I haven't looked in a while. It's sitting in my shop covered with a tarp.



Mine is a post-Horizon, Seacore model but not a 2011. I bought it last year. No Cadillac converter.




Nope, just 300 ponies. I think the only 5.7 engines direct from Mercruiser turning 325 HP are carbureted. I was considering one of those strokers like Island Trader got, but couldn't find one with closed cooling.

Dave

no carb'd engine are available from merc - can't pass emissions...

i have not seen one of those "seacore" engines - heard about them,but not seen.

the merc engines have a "dry joint exhaust system - meaning,no water is pumped through the mount point where the riser meets the mainfold - pretty durable set up - haven't seen any failures from them...

only problems i've seen - is the water pressure sensors - back of the engine- power steering cooler,is where it's located - seen a few of these go bad...other than that - nothing...
my own rig,it's got a 5.7mpi,horizon engine - it's an older engine - '02,and it's been 100% trouble free - it's got just about 500hrs on it...i've used quite a few of these on repowers,in both stern drive applications and inboard systems - all with similar results...


make sure you "wheel" that engine,so it just about "bumps" the rev limiter...


the bravo drives,they're a very good drive,very durable simple basic maintance on them...
i have not seen a bravo III drive,since the update,with any kind of corrosion problems - one client of mine has a crowneline,BIII drive - it's an '06 - no corrosion anywhere - it's a slipped boat...

side note:antifouling paint - you really should have a gap,of 1" around the perimiter of the transom assembly,where there's absolutley no paint - leave that area clean - failure to follow this,can result in a galvanic reaction,between the copper based antifouling paint and the aluminum transom plate...

[Blue_Heron]

Thanks for the good advice. I may have some more questions for you when I start installing outdrive and engine.

Originally Posted by pelican

no carb'd engine are available from merc - can't pass emissions...

There's some info on the Mercruiser web site saying the 2011 regs apply to new boats, not repowering boats manufactured before 2010. As of last February, they were still offering a carbed 5.7 crate engine at 325 HP as a repower option. Not a complete drop-in, just engine, ignition system, and fuel system.

http://www.mercurymarine.com/media/m...nformation.pdf

Don't know if it's still available.
Dave

[pelican]

Originally Posted by Blue_Heron

Thanks for the good advice. I may have some more questions for you when I start installing outdrive and engine.



There's some info on the Mercruiser web site saying the 2011 regs apply to new boats, not repowering boats manufactured before 2010. As of last February, they were still offering a carbed 5.7 crate engine at 325 HP as a repower option. Not a complete drop-in, just engine, ignition system, and fuel system.

http://www.mercurymarine.com/media/m...nformation.pdf

Don't know if it's still available.
Dave

that's not a new motor - merc reman,is alot different than new motors...

merc offers no carb'd new motors