Time to change manifolds (pics)?

[boatgrunt]

94 Crownline with 5.7 Alpha I - The boat has about 400 hrs on it. The last owner used it very little in salt (maybe 2/3 times at most), maintained the boat well and always flushed with fresh water. I ran the boat in saltwater all summer but flushed every time with salt-away. I do not know the age of these manifolds. Given their condition per the pictures, do you think they need to be replaced? Thanks

 

[Manipulator]

Re: Time to change manifolds (pics)?

I think they look fine, looks like plenty of water can pass through. The riser, its hard to tell. Looks like its getting some corrosion in there but looks to have room for water to pass through. You could try to clean it out some. Does the engine run hot at all?

 

[Haut Medoc]

Re: Time to change manifolds (pics)?

I would change them if you are going to continue salt water use.......
The thing with manifolds is they don't go bad until they go bad.....
12 years old & 400 hours, you are on borrowed time, IMHO......JK

 

[boatgrunt]

Re: Time to change manifolds (pics)?

I was planning on replacing them but started to question if it was necessary once I peeled the onion. That being said, I've dealt with the nightmare of "water in engine", and would much rather be safe than sorry. I've pretty much determined that if anyone even raises a question as to their legitimacy per the pics I've posted, I am going to just replace them.

Manipulator - the engine runs at 175, which is normal, and I've never had an overheating problem except once when I idled too long...operator error.

 

[Scaaty]

Re: Time to change manifolds (pics)?

I'd replace them, and then YOU will be in control of future corrosion protection. I always (even though a pain in the posterior) flush with fresh, then saltaway after every use

 

[bruceb58]

Re: Time to change manifolds (pics)?

They look fine to me. Just check for flatness and make sure the thickness of the interior wall at the mating surface is at least 1/4".

If you decide to change manifolds/risers and look at them at the end of next year they will look no better than what you are looking at there.

 

[imported_rosco]

Re: Time to change manifolds (pics)?

they are toast, replace them.

once you start to get flakeing inside the water jackets, like your risers are showing, and the top picture of the manifold inner water jacket is showing, its only a flake away from starting to leak water into your engine,.

the risers are definatly done. you could roll the dice with the manifolds for a couple more years, but the risers need to go now. it is usually the risers that betrey you first.

stainless marine makes a nice set of bolt on stainless risers that will give your engine a good look, and last longer than the cast iron replacements.

 

[bruceb58]

Re: Time to change manifolds (pics)?

I certainly don't see any flaking in these pictures. In fact, what I see is just a brown coating.

Boatgrunt... it is your call but if there is no flaking I would say you are fine.

 

[Autotech1]

Re: Time to change manifolds (pics)?

I dont see any flaking, just some minor deposits.

 

[Scaaty]

Re: Time to change manifolds (pics)?

The problem (those mans are toast after 12 years, flaking or not) is that the places your looking rarely cause as much a problem as way down at the bottom of the Man's where that saltwater has been eating away (salt starts the corrosion, and fresh water won't stop it) at the cast iron, looking for a way into the cylinder. I just replaced a Thermostat housing that looked fine (better than that stuff in your pix), but if you flipped it over, you could punch your finger through the cast iron. Junk'em

 

[cobra 3.0]

Re: Time to change manifolds (pics)?

If they have run only one summer in salt, they're probably just fine. In fresh water they can last and last and last. Mine are 20 years old.

 

[Scaaty]

Re: Time to change manifolds (pics)?

If they have run only one summer in salt, they're probably just fine. In fresh water they can last and last and last. Mine are 20 years old.

But this applies to this story...
400 hrs on it. The last owner used it very little in salt (maybe 2/3 times at most)

 

[bruceb58]

Re: Time to change manifolds (pics)?

I think he meant 2 or 3 times...not 2/3 of the time.

 

[Haut Medoc]

Re: Time to change manifolds (pics)?

I'm with Robbie....
Roll the dice & good luck...
Or replace them & know where you stand...
Failure of a manifold/riser can/will be catastrophic.....
Not only to your engine, but breaking down where you really don't want to......
If you are gonna boat in salt water, what I am seeing will not last long.........JK

 

[boatgrunt]

Re: Time to change manifolds (pics)?

I did mean 2 or 3 times...not 2/3 of the time.

As stated, I planned to replace them if there was any debate. Clearly there is, so I am going to install new manifold/riser this spring. I feel even better about the decision since I don't know there age and plan to use them extensively in salt water.

Would you recommend the Merc manifolds or an aftermarket set? Either way, which site has good prices?

Thanks for all the help!

 

[Scaaty]

Re: Time to change manifolds (pics)?

In salt ONE time is enough to start the process.....I don't care what you try to flush it with after that....rust never sleeps

 

[bruceb58]

Re: Time to change manifolds (pics)?

Two of my local mechanics reccomend the OEM ones. They claim that there is a quality difference and that the extra life you get with the OEMs offsets the price difference.

Google Fast Eddies Marine on the net. They discount OEM parts more than any site I have seen.

 

[ziggy]

Re: Time to change manifolds (pics)?

from what i read. good idea to replace them. i did that on my first engine and felt much better about it. didn't on my second boat and just near paid for it. yep. a manifold leak, water in the oil and stuff. you boatin in the big salt pond i'd think even a better idea. i don't know if oem is better or not. depends on the price difference i'd think. i did aftermarket and got about 1/2 price from oem. i am really an oem guy too. oem parts always work better it seems to me. i used performance product technologies manifolds. theyz ceramic coated i think. look nice enough to me and works fine. in salt it sounds like ya R&R manifolds very often. so yer gonna be R&Ren em often too. so if there's a good savings on aftermarket, ya might consider going that way.......still i think oem is always best, but ya gotta weigh what yer gonna do with em vs the cost i guess........i kinda like american made products too. the performace product wasn't made in usa, but it was made in canada, which to me was close engouh for this day and age. i felt better about than the ones made in china.....i think ya've made a good choice in replacein them. better safe than sorry and ya also know where it is ya stand.........