2004,496ho questions
09-09-2015 | 02:26 PM
#1
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From: prince george,va
2004,496ho questions
looking at a newer boat that is powered by twin 496ho.i don't know a lot about these motors other than they don't make them anymore.are they good motors?h/p rateing and torque?any advise would be great.thanks.
09-11-2015 | 12:01 PM
#2
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From: Tygart Lake, WV
Search on this forum form a thread titled 496 reliability. Lots of good info on that one.
I bought mine 2 years ago and have just hit 100 hrs usage, total 462 hrs on the engine. Had to replace an IAC valve last year but other than that just normal maintenance. Turn the key and enjoy. They are easy to maintain, have Merc engine guardian feature and closed cooling system. Downside is when there is a sensor problem you need to have a Merc scan tool capability to fix. I bought one and it's worth every penny.
If you are planning on modding the engine versus staying stock internal I would look elsewhere. The factory hyperuetetic pistons are the weak link when a power adder or larger cam, heads etc are added.
Btw.. 496 HO 425 hp and 500 tq. Both ratings at the crank.
I bought mine 2 years ago and have just hit 100 hrs usage, total 462 hrs on the engine. Had to replace an IAC valve last year but other than that just normal maintenance. Turn the key and enjoy. They are easy to maintain, have Merc engine guardian feature and closed cooling system. Downside is when there is a sensor problem you need to have a Merc scan tool capability to fix. I bought one and it's worth every penny.
If you are planning on modding the engine versus staying stock internal I would look elsewhere. The factory hyperuetetic pistons are the weak link when a power adder or larger cam, heads etc are added.
Btw.. 496 HO 425 hp and 500 tq. Both ratings at the crank.
09-11-2015 | 01:34 PM
#3
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From: Ft. Worth TX
A quality scan tool is great to have for any MPI engine. I will add scan tool is not the fix all especially if you do not know what the specs of all the parameters should be. It is important to know how to read all the parameters and spend the time in freeze frame history to determine problem areas that matters.
example can anyone throw out all the 5 volt sensors and reference signals that a 496 has and then also the same for DTS apps ? What is smart transom ? there is a lot more to it than thinking you are going to scan and fix your 496 . Yes they can be great motors but also can be real problems with them that will eat your lunch.
Most marine techs hate working on these motors and even more so the 496's with catalyst systems. Some 496's are problem free and there is some that always have problems. There is about 5 to 10 common problems with 496's regardless depending on year and model.
just saying not to scare you. Proper maintenance and on time maintenance is the one of the keys especially for the 496. It is wise to do fuel pressure test twice a year and have it scanned at least once a year regardless before getting after it.
the 3 most common problems with 496's
IAC
IAC muffler
water pressure sensor
Older 496's depending on engine serial number can have NLA cam sensor in which can be a costly repair. Just saying
example can anyone throw out all the 5 volt sensors and reference signals that a 496 has and then also the same for DTS apps ? What is smart transom ? there is a lot more to it than thinking you are going to scan and fix your 496 . Yes they can be great motors but also can be real problems with them that will eat your lunch.
Most marine techs hate working on these motors and even more so the 496's with catalyst systems. Some 496's are problem free and there is some that always have problems. There is about 5 to 10 common problems with 496's regardless depending on year and model.
just saying not to scare you. Proper maintenance and on time maintenance is the one of the keys especially for the 496. It is wise to do fuel pressure test twice a year and have it scanned at least once a year regardless before getting after it.
the 3 most common problems with 496's
IAC
IAC muffler
water pressure sensor
Older 496's depending on engine serial number can have NLA cam sensor in which can be a costly repair. Just saying
Last edited by BUP; 09-11-2015 at 05:01 PM.
09-17-2015 | 04:58 PM
#5
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NLA Pre-2004 Cam Sensor with shallow timing cover boss
Hi,
How much are you getting for the older sensors?
How much are you getting for the older sensors?
A quality scan tool is great to have for any MPI engine. I will add scan tool is not the fix all especially if you do not know what the specs of all the parameters should be. It is important to know how to read all the parameters and spend the time in freeze frame history to determine problem areas that matters.
example can anyone throw out all the 5 volt sensors and reference signals that a 496 has and then also the same for DTS apps ? What is smart transom ? there is a lot more to it than thinking you are going to scan and fix your 496 . Yes they can be great motors but also can be real problems with them that will eat your lunch.
Most marine techs hate working on these motors and even more so the 496's with catalyst systems. Some 496's are problem free and there is some that always have problems. There is about 5 to 10 common problems with 496's regardless depending on year and model.
just saying not to scare you. Proper maintenance and on time maintenance is the one of the keys especially for the 496. It is wise to do fuel pressure test twice a year and have it scanned at least once a year regardless before getting after it.
the 3 most common problems with 496's
IAC
IAC muffler
water pressure sensor
Older 496's depending on engine serial number can have NLA cam sensor in which can be a costly repair. Just saying
example can anyone throw out all the 5 volt sensors and reference signals that a 496 has and then also the same for DTS apps ? What is smart transom ? there is a lot more to it than thinking you are going to scan and fix your 496 . Yes they can be great motors but also can be real problems with them that will eat your lunch.
Most marine techs hate working on these motors and even more so the 496's with catalyst systems. Some 496's are problem free and there is some that always have problems. There is about 5 to 10 common problems with 496's regardless depending on year and model.
just saying not to scare you. Proper maintenance and on time maintenance is the one of the keys especially for the 496. It is wise to do fuel pressure test twice a year and have it scanned at least once a year regardless before getting after it.
the 3 most common problems with 496's
IAC
IAC muffler
water pressure sensor
Older 496's depending on engine serial number can have NLA cam sensor in which can be a costly repair. Just saying
09-17-2015 | 06:13 PM
#6
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From: Moultonborough NH
I have 06 496 HO's in my Cigarette and I run the piss out of them. They never miss a beat and fire up every time I hit the button. There is certainly something to be said for turn key reliability like that. The stock pistons don't like detonation and that is the dilemma I am up against right now. I want more power but it is a very slippery slope with these motors. If you will remain happy with what your boat delivers for performance, I don't think the 496's will let you down, they will give you tons of reliable boating. If you think you may want more down the line, then 502's are a much better platform to add power to.
09-17-2015 | 09:57 PM
#7
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From: Ft. Worth TX
SDfever sorry I have been out of town and finally have a bit of time to come up here. The cost of the cam sensor is 175 dollars shipped to your door. I would like to know what you have exactly. Stock app ?, Stock parts app ? plus year model and so on. My buy in cost was way more than 175 as I had only 10 made for current testing to see how well these are going to work before having 100's of them made. I would want complete engine scanning done to make sure all engine parameters are within spec beforehand compared to installing the cam sensor and running around for however long. Anyways I would even be willing to come out to you for a day to see if we are good to go. I will bring my scan tools and other related items.
My reason for this is because I have not seen nor worked on early 496 models this year at all, everything has been 2006 and up even including Volvo Penta 8.1 's. The new cam sensor made I have is for 2001 thru early 2004 496's and I have not been able to test it in these apps..
My reason for this is because I have not seen nor worked on early 496 models this year at all, everything has been 2006 and up even including Volvo Penta 8.1 's. The new cam sensor made I have is for 2001 thru early 2004 496's and I have not been able to test it in these apps..
09-17-2015 | 10:44 PM
#8
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From: Michigan
