Problems with MERC 496HO MPI ???
05-22-2008, 03:55 PM
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Problems with MERC 496HO MPI ???
Hi!
I'm new at OSO. Great site/forum! I'm from Germany so please excuse some mistakes...
I'm going to buy a used 2001 25ft BAJA Outlaw with a 2006 496HO. I heard that especially this type of engine is causing more problems due to a lot of software etc than e.g. the "old" 502 MAG MPI. I heard that the 502 MPI is more reliable and the maintenance cost is lower because some parts are the same as used in the 7.4 MPI.
Is there anyone who can tell me, if the 496HO is really causing more trouble than others?
Thanks in advance!
Best regards,
Marc.
I'm new at OSO. Great site/forum! I'm from Germany so please excuse some mistakes...
I'm going to buy a used 2001 25ft BAJA Outlaw with a 2006 496HO. I heard that especially this type of engine is causing more problems due to a lot of software etc than e.g. the "old" 502 MAG MPI. I heard that the 502 MPI is more reliable and the maintenance cost is lower because some parts are the same as used in the 7.4 MPI.
Is there anyone who can tell me, if the 496HO is really causing more trouble than others?
Thanks in advance!
Best regards,
Marc.
05-22-2008, 04:31 PM
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Youneed the serial # to find out if it was after 2004 when they worked out the issues with the pushrods, thats what killed 2 of mine, I have 2 of the new ones in my 34 and they are fine.
Hi!
I'm new at OSO. Great site/forum! I'm from Germany so please excuse some mistakes...
I'm going to buy a used 2001 25ft BAJA Outlaw with a 2006 496HO. I heard that especially this type of engine is causing more problems due to a lot of software etc than e.g. the "old" 502 MAG MPI. I heard that the 502 MPI is more reliable and the maintenance cost is lower because some parts are the same as used in the 7.4 MPI.
Is there anyone who can tell me, if the 496HO is really causing more trouble than others?
Thanks in advance!
Best regards,
Marc.
I'm new at OSO. Great site/forum! I'm from Germany so please excuse some mistakes...
I'm going to buy a used 2001 25ft BAJA Outlaw with a 2006 496HO. I heard that especially this type of engine is causing more problems due to a lot of software etc than e.g. the "old" 502 MAG MPI. I heard that the 502 MPI is more reliable and the maintenance cost is lower because some parts are the same as used in the 7.4 MPI.
Is there anyone who can tell me, if the 496HO is really causing more trouble than others?
Thanks in advance!
Best regards,
Marc.
05-22-2008, 05:56 PM
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Ok! I'll try to find the serial number. Have to contact the dealer for that. Besides this, anyone with any other problems regarding the 496HO?
05-22-2008, 07:27 PM
#5
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MERCRUISER SERVICE BULLETIN 2001-6 "Required 496 MAG HO / 8.1S
HO Push Rod Replacement"
2001-2002 MCM 496 MAG HO sterndrive engines (s/nos OM025976
through OM025985 & s/nos OM061091 through OM061773) and MIE
8.1S HO inboard engines (s/nos OM026663 through OM027049)
Warranty codes: MM72, MX16 & Uniform Failure Observation (UFO) 423
-40
A machining operation was omitted on the intake & exhaust valve push
rods used in the the engines listed. This situation can cause the push
rods to fail due to interference w/ the rocker arm. All intake & exhaust
valve push rods must be replaced w/ new parts that have a machined
taper at each end.
Copy of bulletin was sent to all boat manufacturers. Merc lists
replacement intake valve pushrod set, exhaust valve push rod set,
exhaust manifold to cylinder head gasket, rocker arm cover gasket,
rocker arm.
Mine have nearly 500 hours on them and run flawlessly.
HO Push Rod Replacement"
2001-2002 MCM 496 MAG HO sterndrive engines (s/nos OM025976
through OM025985 & s/nos OM061091 through OM061773) and MIE
8.1S HO inboard engines (s/nos OM026663 through OM027049)
Warranty codes: MM72, MX16 & Uniform Failure Observation (UFO) 423
-40
A machining operation was omitted on the intake & exhaust valve push
rods used in the the engines listed. This situation can cause the push
rods to fail due to interference w/ the rocker arm. All intake & exhaust
valve push rods must be replaced w/ new parts that have a machined
taper at each end.
Copy of bulletin was sent to all boat manufacturers. Merc lists
replacement intake valve pushrod set, exhaust valve push rod set,
exhaust manifold to cylinder head gasket, rocker arm cover gasket,
rocker arm.
Mine have nearly 500 hours on them and run flawlessly.
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05-23-2008, 07:37 AM
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MERCRUISER SERVICE BULLETIN 2001-6 "Required 496 MAG HO / 8.1S
HO Push Rod Replacement"
2001-2002 MCM 496 MAG HO sterndrive engines (s/nos OM025976
through OM025985 & s/nos OM061091 through OM061773) and MIE
8.1S HO inboard engines (s/nos OM026663 through OM027049)
Warranty codes: MM72, MX16 & Uniform Failure Observation (UFO) 423
-40
A machining operation was omitted on the intake & exhaust valve push
rods used in the the engines listed. This situation can cause the push
rods to fail due to interference w/ the rocker arm. All intake & exhaust
valve push rods must be replaced w/ new parts that have a machined
taper at each end.
Copy of bulletin was sent to all boat manufacturers. Merc lists
replacement intake valve pushrod set, exhaust valve push rod set,
exhaust manifold to cylinder head gasket, rocker arm cover gasket,
rocker arm.
Mine have nearly 500 hours on them and run flawlessly.
HO Push Rod Replacement"
2001-2002 MCM 496 MAG HO sterndrive engines (s/nos OM025976
through OM025985 & s/nos OM061091 through OM061773) and MIE
8.1S HO inboard engines (s/nos OM026663 through OM027049)
Warranty codes: MM72, MX16 & Uniform Failure Observation (UFO) 423
-40
A machining operation was omitted on the intake & exhaust valve push
rods used in the the engines listed. This situation can cause the push
rods to fail due to interference w/ the rocker arm. All intake & exhaust
valve push rods must be replaced w/ new parts that have a machined
taper at each end.
Copy of bulletin was sent to all boat manufacturers. Merc lists
replacement intake valve pushrod set, exhaust valve push rod set,
exhaust manifold to cylinder head gasket, rocker arm cover gasket,
rocker arm.
Mine have nearly 500 hours on them and run flawlessly.
The dealer gave me a serial# 339079 via telephone!? Is that the right one???
Regards,
Marc.
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05-23-2008, 12:15 PM
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I got a 2002 25 outlaw with the 496 mag HO with over 500hrs on her and it's running just fine! I've had several problems... but nothing directly related to the motor itself.
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05-23-2008, 01:18 PM
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Thank for the thread.
I just bought a '02 34' Powerquest with 496 HO's.
They have 300 hours of which I put on 3. They have 190 hours under 1500 rpm per my mechanic. All 16 cylinders are 155-160 psi on the compression.
They Run Great.
I'll be checking the serial numbers though
I just bought a '02 34' Powerquest with 496 HO's.
They have 300 hours of which I put on 3. They have 190 hours under 1500 rpm per my mechanic. All 16 cylinders are 155-160 psi on the compression.
They Run Great.
I'll be checking the serial numbers though
Last edited by Shawn D; 05-23-2008 at 01:22 PM.
