IMPELLER IN OUT DRIVE

ambush68

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MER CRUISER 5.0 305 CI 2002 MPI 240 HP ( CANT FIND SER NUM)

I LOOKED IN THE MANUAL A DONT FIND WHAT I'm LOOKING FOR.

Q ? DOES A BRAVO THREE DRIVE HAVE AN IMPELLER IN THE LOWER UNIT?

I ASK BECAUSE I AM OVER HEATING DUE TO GROUNDING AND HAVE A NEW IMPELLER, THERMO STAT AND NEW RISER AND EXHUST MANIFOLDS AND STILL GOING TO 180 WITH ALARM GOING OFF...

WHAT ELSE COULD BE CLOGGED WITH SAND IN THE LOWER UNIT.?
 
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dubs283

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DOES A BRAVO THREE DRIVE HAVE AN IMPELLER IN THE LOWER UNIT?

WHAT ELSE COULD BE CLOGGED WITH SAND IN THE LOWER UNIT.?
first off, there's no need to yell

bravo does not have an impeller in the drive, only an engine mounted sea water pump

debris can become lodged in a cooler/heat exchanger

have you backflushed the drive to ensure good water flow?
 

ambush68

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first off, there's no need to yell

bravo does not have an impeller in the drive, only an engine mounted sea water pump

debris can become lodged in a cooler/heat exchanger

have you backflushed the drive to ensure good water flow?
I LIKE THE CAPS MY EYE SIGHT IS BAD SORRY..
I don't have a heat exchanger? I have a hose connection in eng compartment I'll try that next.
Could maybe be the flappers?

I'm thinking of dropping the lower unit look for something clogging up the works?
 
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I LIKE THE CAPS MY EYE SIGHT IS BAD SORRY..
I don't have a heat exchanger? I have a hose connection in eng compartment I'll try that next.

I'm thinking of dropping the lower unit look for something clogging up the works?
If your using a computer, you can make the text size larger on your screen. No need to struggle... press and hold down the CTRL button and the + sign button at the same time. You can do this more than once to continue larger... To switch to smaller size use the - button instead.
 

dubs283

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I have a hose connection in eng compartment I'll try that next.
Could maybe be the flappers?

I'm thinking of dropping the lower unit look for something clogging up the works?
possibly failed/broken flapper(s) blocking the exhaust. it is important to have proper flow into AND out of the cooling system but ime the "in" side of cooling is where most overheat issues arise

yes, removing the drive and inspecting is a good idea, check both intake and exhaust passages for blockage.

check the input side of the oil cooler, then backflush towards the intake (drive) side, ensure good flow this direction. then you can keep moving towards the engine looking for blockages, decreased flow, etc
 

tpenfield

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Remove the outdrive to check for a clog at the hose inlet at the bell housing BUT DON'T take off the lower unit, if that is what you were thinking. You will have a mell of a hess on your hands.
 

ambush68

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Remove the outdrive to check for a clog at the hose inlet at the bell housing BUT DON'T take off the lower unit, if that is what you were thinking. You will have a mell of a hess on your hands.
Ok thks for reply.
Lower unit vs out drive? lower unit meaning where the gimble is housed vs just breaking it apart lower down? Sorry new to the lingo.
 

ambush68

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possibly failed/broken flapper(s) blocking the exhaust. it is important to have proper flow into AND out of the cooling system but ime the "in" side of cooling is where most overheat issues arise

yes, removing the drive and inspecting is a good idea, check both intake and exhaust passages for blockage.

check the input side of the oil cooler, then backflush towards the intake (drive) side, ensure good flow this direction. then you can keep moving towards the engine looking for blockages, decreased flow, etc
Thks for your reply. Flushed out for long time already, going to try the hose connection on the interior the prev owner installed. Guy told me no water coming form the propeller.
 

dubs283

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Ok thks for reply.
Lower unit vs out drive? lower unit meaning where the gimble is housed vs just breaking it apart lower down?
i believe post was referring to removing just the lower half of the drive

mercruiser sterndrives are composed of two halves, the upper driveshaft housing and the lower gearcase/gear housing

remove the entire drive assy for inspection, disconnect speedo coupler, remove trim pin, remove six nuts at bell housing studs, slide drive aft and uncouple shift cable end from linkage in the drive and remove the drive

bravo drives are quite heavy/cumbersome, its in your best interest to use a drive jack/stand to aid in removing
 

ambush68

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i believe post was referring to removing just the lower half of the drive

mercruiser sterndrives are composed of two halves, the upper driveshaft housing and the lower gearcase/gear housing

remove the entire drive assy for inspection, disconnect speedo coupler, remove trim pin, remove six nuts at bell housing studs, slide drive aft and uncouple shift cable end from linkage in the drive and remove the drive

bravo drives are quite heavy/cumbersome, its in your best interest to use a drive jack/stand to aid in removing
Ok that's what I thought he meant thks.
 

dubs283

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Guy told me no water coming form the propeller.
any water exiting from the propeller would be the exhaust side, i was referring to the intake side which during a backflush would be coming out the intake ports on either side of the gearcase/lower half
 
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