Merc 525's

[MOBILEMERCMAN]

Frank I don't follow the difference between the pleasure and race boats. Are you saying pleasure boats are harder on headers? I would think so.

Would you agree all headers regardless of brand are likely to leak at some time?

 

[DAREDEVIL]

frank i don't follow the difference between the pleasure and race boats. Are you saying pleasure boats are harder on headers? I would think so.

Would you agree all headers regardless of brand are likely to leak at some time?

i would think so,,,everything will fail at one time !!!!

 

[95south]

is merc having any other issues with their other engine pkg?
what headers are on there other products.
With the issue now on the 525s, I believe the headers are not leaking
is it possible , just to be a design or engineering issue with the 525 pkg?

 

[gerritm]

Frank I don't follow the difference between the pleasure and race boats. Are you saying pleasure boats are harder on headers? I would think so.

Would you agree all headers regardless of brand are likely to leak at some time?

Jim, I was told that the 525's have a longer or higher cam lobe that keeps the valves open longer and tend to act more like a pump to draw in water and cause reversion. It can happen whether the header is leaking or even when you are decellerating and water washes back up the exhaust pipes. I had a broken inner metal flapper or check on my starboard engine exhaust pipe. The external rubber flapper was fine. The water got into the #8 cylinder taking out the top of the piston. When we pressure checked the headers at that re-build, they were holding fine. But you could see water marks in the exhaust port. I replaced the inner and outer flappers and so far no problems even though the headers have leaked and been re-welded. I am not sure if this is more true of the 525's, but it might explain some of the reversion problems. If you see an abnormal amount of exhaust steam coming out of the pipes, pressure check you headers, that's how we found the leaks.

 

[95south]

I have heard the same thing about the cam
the boat with the issue has inner flaps as well as rubber flaps on the out side

 

[Geronimo36]

Would you agree all headers regardless of brand are likely to leak at some time?

From what I've seen over the years, yes! Some brands seem to fair better than others (Stellings) and some designs within the same brand fair better than others.

The merc issued CMI's seem to be the most prone to failure, they were actually built to Merc. specifications and they use a different gauge SS.

The swept back headers on the 525's, 600sci and 700sci's seem to be the most problematic these days from what I've seen. We have had three boats at the marina with triple 525's, 600's and 700's...all have seen failures around the 80-100 hr mark. These boats were professionally maintained and flushed after every single use. It's to the point where the owners are completely fed up with CMI and don't ever want to own a boat with them again.... They love the mercury power so that's going to be hard for them to deal with.

I must say that something has changed because the older CMI's used to last a lot longer. Yeah, they could develop a leak here or there but they could usually be fixed. The newer design pattern seems to have a very short service life and last no more than a few seasons.

 

[Geronimo36]

is merc having any other issues with their other engine pkg?
what headers are on there other products.
With the issue now on the 525s, I believe the headers are not leaking
is it possible , just to be a design or engineering issue with the 525 pkg?

Well, I'm glad to see that it's not the headers for a change!!!!:26:

I'm not aware of any other major issues other than some bad ECU's and IAC valves failing here/there but I'll check around.

 

[baja27]

A class action law suit would definitely wake up the sleeping giant!! Everyone who has had issues with exhaust failing should sign up for the law suit.

 

[MOBILEMERCMAN]

I don't know to comment on design issues. I am not saying there are not any problems either. My point is boat owners need to pay particular attention when your boat has headers. As others have mentioned pressure check no less than seasonally if not more. Flappers are a important part of the exhaust system check then frequently they live in a tough environment. I see boats with them removed often. It doesn't hurt to drain headers after use. I like to look up tailpieces to see exhaust pattern so you can recognize a change.

I find it unfortunate water in cylinders often goes un noticed and eventually takes a motor out. Granted it is hard to tell if a motor is loaded up with water. It often sounds the same as if it were flooded with fuel. The way the starter sounds offers clues too.

There are boat owners that notice changes in how a motor is acting or sounds even the slightest. These are the same guys others call lucky.

 

[Sean Stinson]

300 hrs @ 75-100 mph is roughly 22,500 - 30K miles, somethings skewed Jim. You sure it wasn't 30 hours which is closer as 30 X 100 mph = 3000 miles.

For 6 months I use my boat 2-3 days per week for roughly 3-6 hours a day... Race boats can't even run unless they have a permit and in some places during the week... I could be wrong but I think the hours are skewed a bit.

You have to account for all the idle time for flushing getting in and out of the marina as well as the ICW to the ocean and lets not forget all the times you fire it after testing or whatever you cannot use 75-100 mph as an avg speed!!!!!

 

[Sean Stinson]

And don't forget all the time in the milling circles as well!!!!

 

[Geronimo36]

I know Sean, just provin a point!

Symantics!

 

[Geronimo36]

There are boat owners that notice changes in how a motor is acting or sounds even the slightest. These are the same guys others call lucky.

Jimmy, that's gotta be the best line I've seen all week, very cool!!!:driving:

 

[PARADOX]

Jimmy, that's gotta be the best line I've seen all week, very cool!!!:driving:

True..
I listen a lot more then I look at the gauges.
When I drive, (at higher speeds) ... I'm somewhat rude... Don't talk to me.. don't show me anything, don't point at dolphins in the water.. I am 100% concentrating on engine noise and safety around me.
As far as I go.. the time I look or see the gauges reading something.. it's too late. Even in my cars.. I know every sound it suppose to make.. one little out of place noise.. I check into it.
A few weeks ago I was in the Sarasota PR... lost a fitting in the power steering lines.. Steering as still ok.. but I heared a noise.. Slowed,, stopped.. found the problem.. ran for about 15 seconds with the noise... but saved me a power steering pump. (BTW.. thanks Lenny and Bob for the fluids at lunch. I will return next time we see you guys) :seeya:

 

[Geronimo36]

True..
I listen a lot more then I look at the gauges.
When I drive, (at higher speeds) ... I'm somewhat rude... Don't talk to me.. don't show me anything, don't point at dolphins in the water.. I am 100% concentrating on engine noise and safety around me.

I'm the same way man!!!

People have said to me, "where do you set your drives?" "what number do you set the tabs?"... They also say, "how come you don't have neutral marked?"

I drive by feel, I use my senses. I don't pay attention to numbers like they're bible, it's only a reference.

For what it's worth, I feel that when actions become "mechanical" (drives at 3, tabs at 4 etc.) you loose your sense of awareness! :driving:

 

[PARADOX]

Agreed!
You "Feel" a boat. You can't feel numbers. I can feel when trims are set right, (for a condition or seas) just based on the wakes and spray behind the boat, outdrive / engine noise, vibration, exhust sound. I can tell when the motor RPS are in sink just by the exhust echo. No dial can get even close.
On the subject.. I heared that there are a bunch of legal actions with Merc. and CMI. & Corsa. They all point to the "other" guy. Merc. should take care of the issues.
Here's the problem.... After the warranty is over.. Merc. tells you to fly a kite.

 

[Ratickle]

Agreed!
You "Feel" a boat.

Is that why they are called "She"......:sifone:

 

[PARADOX]

Is that why they are called "She"......:sifone:

Neeaahh !! Nope!!!. not gonna happen.!! ? .... ain't touching this one.. (not here) :leaving:

 

[Steve Miklos]

Jim, I was told that the 525's have a longer or higher cam lobe that keeps the valves open longer and tend to act more like a pump to draw in water and cause reversion. It can happen whether the header is leaking or even when you are decellerating and water washes back up the exhaust pipes. I had a broken inner metal flapper or check on my starboard engine exhaust pipe. The external rubber flapper was fine. The water got into the #8 cylinder taking out the top of the piston. When we pressure checked the headers at that re-build, they were holding fine. But you could see water marks in the exhaust port. I replaced the inner and outer flappers and so far no problems even though the headers have leaked and been re-welded. I am not sure if this is more true of the 525's, but it might explain some of the reversion problems. If you see an abnormal amount of exhaust steam coming out of the pipes, pressure check you headers, that's how we found the leaks.

Yep! The guys racing have dry tailpipes so they never see it.
Steve

 

[gerritm]

Yep! The guys racing have dry tailpipes so they never see it.
Steve

Makes sense.