cracked manifold -- should be found during mech. inspection

[bMcN]

I bought a boat last summer. The pre-purchase mechanical inspection on the Merc 496 MAG came back all-good. This May, Inlet Marine found that "PORT EXHAUST MANIFOLD AT THE BOTTOM OF WATER SUPPLY FOUND EXHAUST MANIFOLD WAS CRACKED WHERE FITTING GOES IN .LOOKS LIKE SOMEONE IN THE PAST - OVER TIGHTEN FITTING WHICH CAUSE EXHAUST MANIFOLD TO CRACK." No one touched the engine between the inspection and the May service at Inlet, which lead me to think the inspection missed the crack.

I didn't have the motor winterized this past winter. A marine mechanic friend of my Dad's says the crack could be from water in the manifold over the winter and that the compression test during the inspection would have flagged the cracked manifold.

So, should I be going after the folks that did the pre-purchase mechanical inspection, or should I be kicking myself for skipping winterization? (Or both)

Thanks for any insights.

-b

 

[wishiniwasfishin1]

I would think your chances of getting any compensation from the inspector would be 'Slim and None' and Slim just left town...

 

[gungadin]

It has been a year since the inspection, chances of compensation will be very low. Not winterizing would be a red flag.

 

[Pineapple Express]

It has been a year since the inspection, chances of compensation will be very low. Not winterizing would be a red flag.

I agree with this. It would be very difficult to prove that the defect was present and overlooked during the inspection. Given the time that has passed....I think you're on your own.

 

[brutus]

I bought a boat last summer. The pre-purchase mechanical inspection on the Merc 496 MAG came back all-good. This May, Inlet Marine found that "PORT EXHAUST MANIFOLD AT THE BOTTOM OF WATER SUPPLY FOUND EXHAUST MANIFOLD WAS CRACKED WHERE FITTING GOES IN .LOOKS LIKE SOMEONE IN THE PAST - OVER TIGHTEN FITTING WHICH CAUSE EXHAUST MANIFOLD TO CRACK." No one touched the engine between the inspection and the May service at Inlet, which lead me to think the inspection missed the crack.

I didn't have the motor winterized this past winter. A marine mechanic friend of my Dad's says the crack could be from water in the manifold over the winter and that the compression test during the inspection would have flagged the cracked manifold.

So, should I be going after the folks that did the pre-purchase mechanical inspection, or should I be kicking myself for skipping winterization? (Or both)

Thanks for any insights.

-b

Not sure where your boat was but it got cold this winter, not winterizing is prob why your exhaust crack me thinks, put away full of water is not good

 

[Corey_lax]

My aunts boat cracked the block during a cold snap in early November a few years ago. Consider yourself lucky.

You’ll never be able to prove that it was missed during inspection even though Inlet said it was overtightened. It very well could have froze

 

[ab1752]

These things crack from the inside out in my experience. Now I just have them swapped out every 300 hours no matter what I don't want to find out the hard way at sea.

 

[Corey_lax]

Are you moored at Barnet? Or do you trailer? Just curious because there is fresh water run off in Port Moody that freezes. I’ve smashed my boat through ice in December. I had to plow a path for about a kilometre in my old fibreglass boat so that the hewescraft behind me didn’t scratch his aluminum lol

 

[wolf]

After A year im sure your SOL , a over heat or even not draining water over winter will crack it easily.....

May i suggest something for you there is some pugs on the under side as well take one out and replace with a brass one with some good marine grease, also should be a bolt on the back side lower bottom get that sized bolt matched with the brass plug/pencil zinc you may have to cut zinc to fit but good for protection and replace every season. at end of year flush and drain your engine and pull both those plugs out so no water is in manifolds.

If you have any questions feel free to PM ive dealt with inboards all my life ...

Good luck Wolf

 

[ab1752]

After A year im sure your SOL , a over heat or even not draining water over winter will crack it easily.....

May i suggest something for you there is some pugs on the under side as well take one out and replace with a brass one with some good marine grease, also should be a bolt on the back side lower bottom get that sized bolt matched with the brass plug/pencil zinc you may have to cut zinc to fit but good for protection and replace every season. at end of year flush and drain your engine and pull both those plugs out so no water is in manifolds.

If you have any questions feel free to PM ive dealt with inboards all my life ...

Good luck Wolf

Wolf what's your take on running the manifolds full of the pink RV antifreeze? That's what I have been doing and it hasn't let me know yet...I am curious to see what the current set of manifolds are like. Also what's your take on Volvo original vs Sierra manifolds? The Sierra ones are on my 5.7 GXI currently, I didn't ask for them, the dealer just went ahead and used Sierra last time around. I pull my boat and fresh water flush each time but still, I will be at just over 300 hours on this set and I am going to pull them off this winter.

Thanks for this, I think this was of useful info for the folks dealing with manifolds.

 

[bMcN]

Are you moored at Barnet? Or do you trailer? Just curious because there is fresh water run off in Port Moody that freezes. I’ve smashed my boat through ice in December. I had to plow a path for about a kilometre in my old fibreglass boat so that the hewescraft behind me didn’t scratch his aluminum lol

Yes, moored at Reed Pt. My slip is about 50m from one of the pipes that drains into Burrard Inlet.

 

[bMcN]

After A year im sure your SOL , a over heat or even not draining water over winter will crack it easily.....

May i suggest something for you there is some pugs on the under side as well take one out and replace with a brass one with some good marine grease, also should be a bolt on the back side lower bottom get that sized bolt matched with the brass plug/pencil zinc you may have to cut zinc to fit but good for protection and replace every season. at end of year flush and drain your engine and pull both those plugs out so no water is in manifolds.

If you have any questions feel free to PM ive dealt with inboards all my life ...

Good luck Wolf

Thanks for the tips. Cheers -Brad

 

[wolf]

No matter what you do closed system or the salt thru the top its just the way its designed. no matter what I did and tried after 4 years I tossed them id rather do that then wait till its hydraulics a motor rght during fishing season ... and worst timing it always seems.

I did switch out to a aftermarket ones out of vancouver and they were great had one riser go but they sent me a new one as it got a hole in side from a bad casting here is the site
for the 5.7 its HGE 5735 what I really liked is no thin water passages HUGE ones on front and back.
Hope that helps bud

http://hgemarine.com/products/manifolds-and-risers.html

 

[Saveth]

compression test during the inspection would have flagged the cracked manifold.
-b

This is incorrect. A compression test let's you know how much pressure the cyclinders can hold during the compression stroke. It lets you know if the rings, valves or head gasket leaks.

When a manifold cracks, a blown motor usually occurs right after because water can now flow into the combustion chamber through the exhaust valve ports. This is why manifolds need to be replaced before this happens. I like to replace mine every 5 to 7 years.

 

[bMcN]

This is incorrect. A compression test let's you know how much pressure the cyclinders can hold during the compression stroke. It lets you know if the rings, valves or head gasket leaks.

When a manifold cracks, a blown motor usually occurs right after because water can now flow into the combustion chamber through the exhaust valve ports. This is why manifolds need to be replaced before this happens. I like to replace mine every 5 to 7 years.

Thanks for the clarification. The engine only had 60hrs on it. Original manifolds were/are aluminum. Replacement is cast iron, and Inlet says I can expect to replace the other aluminum with cast iron "real soon now".

 

[Pineapple Express]

Thanks for the clarification. The engine only had 60hrs on it. Original manifolds were/are aluminum. Replacement is cast iron, and Inlet says I can expect to replace the other aluminum with cast iron "real soon now".

I think most people replace the manifolds in pairs. Why would you wait for something as critical as this!?

 

[noluck]

Thanks for the clarification. The engine only had 60hrs on it. Original manifolds were/are aluminum. Replacement is cast iron, and Inlet says I can expect to replace the other aluminum with cast iron "real soon now".

at 60 hrs it failed, it without any doubt it froze and cracked

 

[ab1752]

No matter what you do closed system or the salt thru the top its just the way its designed. no matter what I did and tried after 4 years I tossed them id rather do that then wait till its hydraulics a motor rght during fishing season ... and worst timing it always seems.

I did switch out to a aftermarket ones out of vancouver and they were great had one riser go but they sent me a new one as it got a hole in side from a bad casting here is the site
for the 5.7 its HGE 5735 what I really liked is no thin water passages HUGE ones on front and back.
Hope that helps bud

http://hgemarine.com/products/manifolds-and-risers.html

This is great, I will definitely check them out. This is the end of season 3 on this set so I'm going to watch them very carefully and change them out in Spring, if not before.

 

[bMcN]

I think most people replace the manifolds in pairs. Why would you wait for something as critical as this!?

I guess the mechanic thought the original would last another season, and was worried I couldn't handle the sticker-shock of having both replaced on an essentially new engine. I'm pretty spooked now and will plan on replacing the other this fall.
Thanks to everyone who contributed to this thread.
-Brad

 

[e-zee]

I guess the mechanic thought the original would last another season, and was worried I couldn't handle the sticker-shock of having both replaced on an essentially new engine. I'm pretty spooked now and will plan on replacing the other this fall.
Thanks to everyone who contributed to this thread.
-Brad

I pull my risers and manifolds off each fall after coho season. I can clean them up and inspect them. New gaskets are cheap. I also run an electric bilge heater with a built in thermostat all fall/winter. It not only keeps the bulge warm it keeps it dry. Electricity is cheap and you can’t put a price tag on peace of mind.