If your engine is running warm Change the exhaust

[joemamma]

I've seen more engines destroyed because people are to cheap to change exhaust manifold/ risers as a preventative action. especially raw water cooled engines. They start to clog and overheat. once one side overheat it makes steam and it has enough pressure to push the water completely out of the engine. Then something cracks, It cools off enough to get it started, and water starts going where it has no business being.
if your lucky it's in the crank case, but your luck may just get you back to the dock.
If not it's in the cylinders , and we all know how much fun it is to pull spark plugs on an omc and your calling sea tow. either way the $500 for new exhaust every 4 or 5 years now turns into thousands.
If you just bought a new to you boat.or if you cant remember when you changed them. Change em now. If your running warm above 2800 rpm it's time. It really sucks overheating with your family and friends aboard. P.M. is the key to reliability.
Just my 2 cent.

 

[Don S]

Re: If your engine is running warm Change the exhaust

either way the $500 for new exhaust every 4 or 5 years now turns into thousands.

First of all, that may be almost true if you are running in salt water. At 4 years they need to start pulling the risers and inspecting yearly. If they are corroding away and plugging up yes replace them. But they usually last 5-8 years in salt water.
In fresh water, they may last as long as the boat and look like new inside.

If you start running warm, find out why and fix it before it gets worse. No matter what is causing it to get warm.

 

[donberry]

Re: If your engine is running warm Change the exhaust

yea, I'd have to disagree if it is a fresh water boat. Unless the lake/river you normally are on is really high in minerals, there really isn't any reason the manifolds will not last the life of the boat. Also, not really sure where I could find a pair of manifolds for my 1988 OMC 4.3l. Maybe $1500 for both sides. Now my brother has a salt water boat and I couldn't afford to own one as so much needs changed ever 5 years or so.

 

[sw33ttooth]

Re: If your engine is running warm Change the exhaust

i agree with the salt water comments that stuff can be nasty on metel.

 

[Don S]

Re: If your engine is running warm Change the exhaust

You need to start your own thread sw33ttooth, your particular situation isn't what this thread is about. To keep from hijacking someone elses thread, it's always best to start a new one of your own.

 

[joemamma]

Re: If your engine is running warm Change the exhaust

yea, I'd have to disagree if it is a fresh water boat. Unless the lake/river you normally are on is really high in minerals, there really isn't any reason the manifolds will not last the life of the boat. Also, not really sure where I could find a pair of manifolds for my 1988 OMC 4.3l. Maybe $1500 for both sides. Now my brother has a salt water boat and I couldn't afford to own one as so much needs changed ever 5 years or so.

I have never seen a fresh water boat. I've heard of them though.

I'd be willing to say 98% of engine failures I see are caused by rotten exhaust.
I actually rotate my manifold replacement with riser replacement. just because of the cost. it's a hard pill to swallow for preventative maintenance. I hear it all the time "I know it's time but I'll try to get one more season out of them". I truly hope they do. The people who can afford to do it and don't , I don't feel bad charging, If you can't afford it , I do.
personally I will never put myself in that situation. It the cost of running in salt water.
I don't like charging people for their misfortune, I like helping them.

 

[Joshua Nichols]

Re: If your engine is running warm Change the exhaust

The ones that where on my boat lasted 24 years..
I call that good longevity..
PO used it in fresh and brackish water only..He also used the boat hard all summer..( He owns a lake house the lucky devil)

Replaced the manifolds this winter with a Osco set.. Found em on E bay for $850.. A little paint.. On they go..
Install was easy.. Kit came with everything needed.. Not a bad deal..
The wing type new.. A set is about $1400..

BTW my old ones never caused the boat to run hot.. They would just leak in the cylinders..

 

[joemamma]

Re: If your engine is running warm Change the exhaust

That's zackly my point. "they would just leak in the cylinders" That's when "BAD" stuff happens. Bad=Expensive

 

[Icyharp]

Re: If your engine is running warm Change the exhaust

I've seen more engines destroyed because people are to cheap to change exhaust manifold/ risers as a preventative action.

CHEAP?, you didn't describe salt water or fresh water till later in the thread. So lets see my boat is 24 years old and has the same exhaust manifolds on it since it came home in '87, the boat looks as new as the day it was bought. So that makes my family or myself cheap? I don't think so. In the future please try to address your concerns a tad different.

 

[Joshua Nichols]

Re: If your engine is running warm Change the exhaust

That's zackly my point. "they would just leak in the cylinders" That's when "BAD" stuff happens. Bad=Expensive

Ummm still yet.. thats not a overheat.. Water in the cylinders.. Nothing expensive came of it.. Other than having to purchase some new manifolds and some gray spray paint..

isn't this the title to the thread?

"If your engine is running warm Change the exhaust"

BTW My engine runs warm.. 170 and under..I like it that way...

and we all know how much fun it is to pull spark plugs on an omc

You must have a Ford engine.. The GM stuff is cake.. Straight in...


Is the next thread going to be.."if you hear a click change your starter"?

 

[Icyharp]

Re: If your engine is running warm Change the exhaust

Is the next thread going to be.."if you hear a click change your starter"?

LOL now that is funny.......

 

[mcleaves]

Re: If your engine is running warm Change the exhaust

Lord knows I've had my share of exhaust failures, but most cooling problems are not IMMEDIATELY the exhaust. I am not trying to diminish the sage advice of annual inspections, and replacing when due, but before someone who is running hot runs off to buy the better part of 1000.00 worth of parts (mine run about 700.00 and then you should also replace all your boots at the same time.) Things like thermostats and raw water pumps are likely the culprit. And I say this as someone who got to spend a day with the coast guard 20 miles offshore years ago from an exhaust fire. I don't screw around when it come to exhausts, but I am also smart about it.

Just MY .02

 

[joemamma]

Re: If your engine is running warm Change the exhaust

Raw water impellers and thermostats should be changed annually.
If you think water in your cylinders is O.K. Then you keep saving your money.

Josh, what's the difference between a wise man and a wise guy?

 

[mcleaves]

Re: If your engine is running warm Change the exhaust

Unbelievable. Don't be an *** and put words in in people's mouth's. Who on here said water in the cyl's was OK? Your solution, out of hand, is that if your engine is running warm replace the manifolds when in all likelihood it's another component. You should replace the manifolds and risers through evidence upon inspection , which includes pressure testing. That is what a mechanic does. I am glad I am not one of your customers. Any part you replace can go bad, so even if you if part of your annual is to replace the t-stat and impeller, a mid-season higher temp condition is STILL more likely to be one of these items. You are not even calling out an overheat, just "running warm". Damn man, I've had a clogged water pickup from a plastic bag that caused me to run warm. I've lost prime while on plane hitting some big swells. Nothing to do the the manifold and she sure ran warm.

Manifolds and risers are NOT the first suspect in a warm running engine, and while inspection if the exhaust should be part of the trouble shooting process, it should NOT be the first item in MAINTENANCE. A friggin long block for most engines is less than 1500. Two knee jerk manifold replacements and you are in the hole.

If your manifolds are getting thin in material (below OEM spec - Don has a great picture of this he posts), the ports are getting clogged, or a pressure test fails then damn straight, replace them now.

 

[Don S]

Re: If your engine is running warm Change the exhaust

If your engine is running warm Change the exhaust

Raw water impellers and thermostats should be changed annually.

You have your opinions on when things need to be changed, that's fine. But your information is just not backed up by any facts or even the manufacturers recommendations.
If someone asks when something should be changed, by all means give your opinion. but don't start a thread with your opinion as if it's some fact of life for everyone, it's not.

This thread is closed.