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-   -   Merc 500 vs 525 questions (https://www.offshoreonly.com/forums/general-boating-discussion/380637-merc-500-vs-525-questions.html)

Ondemand 09-21-2023 10:46 PM

Merc 500 vs 525 questions
 
Hey all, new to the site. I am debating on 3 boats right now . I need advice on making the decision. Boats are (1) 2008 baja 335 with 100 hours twin 496, (2) 2007 baja 405 with 175 hours -twin 525 blue, (3) 2001 Formula 400SS with 450 hours- twin 500 blue. I live in Florida, the boats will be kept dry when not in use. Please advise , thank you

Griff 09-21-2023 11:15 PM

Being that you live in Florida and salt water, I'd get a boat with closed cooling. The 496's and 525EFI's have closed cooling.
You could also have closed cooling added to the 500EFI's for $$$

Ondemand 09-22-2023 07:48 AM


Originally Posted by Griff (Post 4880573)
Being that you live in Florida and salt water, I'd get a boat with closed cooling. The 496's and 525EFI's have closed cooling.
You could also have closed cooling added to the 500EFI's for $$$

That's what I was thinking if I went with the 500s. Between the boats themselves, any knowledge or advice?

Wildman_grafix 09-22-2023 08:34 AM

Not commenting on the boats themselves but can comment on the motors.

I boat in Florida and have HP500EFI motors. NOT closed cooled.

I flush every time with lots of water, back flush the drives then run Salt-A-Way and or Dawn through them. A few years ago I thought I should change the thermostats, they looked almost new.

Very good motors, rebuilt top ends around 320 hours, now have 780ish, still run strong. Excess idling will burn oil.

496HO's less power, more than most say. Top end will be close but every where else not as much. But they are very good long lasting motors and closed cooled. For a more cruiser type of boat that would be my pick. A few of my friends have went to them because they can be pretty much turn key boating.
There are a range of s/n that they had fuel rail issues that could be very expensive to repair, check on that.

525's, I have dyno curves of my motors (HP500EFI's) and 525's from the same dyno tested the same way (Full marine trim, pumps, power-steering, sea water pump headers etc). The power almost overlays a the 500 till about 4400-4500 rpm then the better breathing of the 525's takes over and you see gains. With those gains you have header issues that are costly, cam is harder on valve train but if you do the top ends soon enough that is taken care of. They are closed cooled.
The headers can get expensive to replace, but they are good motors as well.

Rambocj7 09-22-2023 09:11 AM

Those are all very different style boats! Build quality will be better on the Formula than the Baja. AS mentioned, the 496s and 525s will have closed cooling which does require less maintenance when running in salt. For turn key, trouble free boating, I would absolutely take a 496 over any blue motor. The small gains in performance just do justify the maintenance costs associated with blue motors (top end rebuilds, full rebuilds, header issues etc). I've seen some for 496s with 1000s of hours still running strong.
In general, get a survey and have mechanical inspections.

AS far as preference, its hard to beat the Formula 400ss, its always considered to be the 'best of both worlds' type of boat. However, I would steer clear of one with blue motors due to maintenance.

Ondemand 09-22-2023 09:20 AM


Originally Posted by Wildman_grafix (Post 4880598)
Not commenting on the boats themselves but can comment on the motors.

I boat in Florida and have HP500EFI motors. NOT closed cooled.

I flush every time with lots of water, back flush the drives then run Salt-A-Way and or Dawn through them. A few years ago I thought I should change the thermostats, they looked almost new.

Very good motors, rebuilt top ends around 320 hours, now have 780ish, still run strong. Excess idling will burn oil.

496HO's less power, more than most say. Top end will be close but every where else not as much. But they are very good long lasting motors and closed cooled. For a more cruiser type of boat that would be my pick. A few of my friends have went to them because they can be pretty much turn key boating.
There are a range of s/n that they had fuel rail issues that could be very expensive to repair, check on that.

525's, I have dyno curves of my motors (HP500EFI's) and 525's from the same dyno tested the same way (Full marine trim, pumps, power-steering, sea water pump headers etc). The power almost overlays a the 500 till about 4400-4500 rpm then the better breathing of the 525's takes over and you see gains. With those gains you have header issues that are costly, cam is harder on valve train but if you do the top ends soon enough that is taken care of. They are closed cooled.
The headers can get expensive to replace, but they are good motors as well.

Thank you

techman 09-22-2023 09:20 AM

Are you asking which engine or which boat to choose? I wouldn't necessarily pick a boat based on what's in the bilge especially since all three have proven Mercury power.

If you truly want to pick a motor and the boat it comes with, go with newest one.

87MirageIntruder 09-22-2023 09:31 AM

If you are ever going to think about wanting more power from one of these engines, the blue engines are a much better platform as parts availability for speed parts is much greater. For trouble free longevity, stock 496s are hard to beat.

Sydwayz 09-22-2023 10:15 AM

400SS boats have a tendency to tear up Bravo drives. That's a lot of boat to propel through B1 drives, and that's why they can brake. t500hps posted about this in his search for a 400SS, that nearly ALL the 400SS boats he saw with B1 drives said "fresh drives". That's why he bought a boat with VolvoPenta diesels and their massive drives. And he's very happy with the setup and the associated fuel mileage.

Ondemand 09-22-2023 10:22 AM


Originally Posted by 87MirageIntruder (Post 4880606)
If you are ever going to think about wanting more power from one of these engines, the blue engines are a much better platform as parts availability for speed parts is much greater. For trouble free longevity, stock 496s are hard to beat.

thank you


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