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brenna_8

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"Thanks For reading, I have a

"Thanks For reading, I have a 1986 Volvo Penta Bayliner, 4 cylinder, and my question is this, is has a radiator heat exchange, could that be set up as a salt water? Because someone had told us that it would be over-heating the way that it does because it is set up as salt water, and something about a radiator? What we would really like to know is we had replaced the manifold, many of bellows, and lots of money and parts later, we are still overheating could anyone help us in the right direction as to why, we are also new at all of this, we have had the boat for three years or better and every season same story, heat- heat and more heat, please help, thanks so much Brenna"
 
"Brenna, whats your HP and/or

"Brenna, whats your HP and/or model model number?
I think it would be a AQ125a/or/b. Remove the heat exchanger and disassemble it. Dry rotted impellers clog up the small paths in it. Replace the gasket or use gasket material if you must.I would clean the coolant resivor while you are at it. Your cooling system must be completely clean or you will have issues. Listen to El Pascador, he know's these motors. Good luck!
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"These have square "O"

"These have square "O" rings on each brass/cooper water line and the area where the pipe comes into the water pump (the the right of the arrow) would collect the dead water pump parts and restrict the out put.

To re assemble -you must put the rubber rings in with grease, if any kind of sealer gets on them they really just twist and leak.

They were fresh water cooled so they don't need a few marine parts. Would not convert to raw water as you may loose some of these parts.

Are you running hot on plane and cool at idle- many posts about the raw water intake manifold just below the exhaust bellows and how it buckles and sucks air when on plane. Put a piece of clear hose between the bell housing and the water pump to check for bubbles."
 
"Thank you guys for getting ba

"Thank you guys for getting back to me. And yes, Brandon, you are so right it is a AQ125A. I read last night all kinds of posts, but we were not sure if it could be a salt water boat, and overheat in the river. WE are so clueless when it comes to this boat, and we have a car mechanic that has never worked on a boat before, and getting him to even work on it these days is difficult, what I would like to do, is find someone that knows what they are doing besides knowing how to take us broke while doing whatever that needs to be done, you know? Ok, I will let Jeff know that you guys had got back to us, and I will get back to you, thank you so much!"
 
"Brenna, check the raw water h

"Brenna, check the raw water hose connector in the outdrive as William suggested. This is by far the most common cause of overheating in your type of engine/outdrive combination. Hose connectors are cheap and not difficult to replace. Search the forum for the words raw water hose connector, there are many posts about this.



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"Another question, My mechanic

"Another question, My mechanic seems to think that now our heat exchanger is bad? Could this be true? Or is he again jumping to another expensive comclusion? I did not witness what went on today, all that I know is that he is saying that it is the heat exchanger, how much do they cost, and where would we get one? It is a viking? I am ready to sell this thing, but Jeff seems to think that it is going to work, I had also told him about what you guys have said, and I have showed him the pictures, and he agrees with Eddie, so could it be the heat ecxhanger?"
 
"They rarely "go bad"

"They rarely "go bad" to the point of needing replacement. Read the previous posts about cleaning them.

Re: "we have a car mechanic that has never worked on a boat before,.."
I don't want to come across as being an "a-- hole" BUT... car mechanics by and large do not do a good job on marine engines. If its a burned valve/bad head issue ( yours isn't) or a carb problem, they often do OK. HOWEVER... if it's cooling system related, they almost always are in over their heads and resort to the old shoddy car mechanic technique of replacing everything until its fixed or you run out of money.

Unless your cooling system is loosing antifreeze, it is unlikely that the heat exchanger needs replaced. Trouble shooting cooling system problems is a bit tedious, but there are only a few places that cause problems and as far as I can see the previous posts have covered them all....except for two of my favorites: improper gasket seal on the raw water strainer, if equipped allows air to be sucked in. and, barnacles in the water passages within the drive... (a coat hanger will fix this)

A question for clarification: You say "overheat"
OK... when and under what conditions? On a plane, at cruise, at idle... when it overheats does it cool off at idle?"
 
"Just finished reading a post

"Just finished reading a post that said "radiator shop" Have to agree about auto mechanics and if you really want a tragedy get involved with a heavy truck mechanic. You can make a boat mechanic into a truck mechanic, but really hard to go the other way."
 
"Brenna, I too would pay atten

"Brenna, I too would pay attention to the good advice being offered here.
You may need to find a person more capable to be doing this work for you.

I also have a small V/P repair biz.... but my specialty is not necessarily the OHC 4's. And Yes..... El P is much more knowledgeable then I am on this particular engine model. I do work on them, and that being said; I don't think this H/E (heat exchanger) needs to be replaced, and I'd never recommend that it be removed!
That is just plain silly thinking!

Here is my suggestion as to a starting point while moving in the direction of flow of the incoming sea water:

Check the lowest most O ring in the path of the sea water.... The Pivot Tube O ring!
Next, the water neck fitting/special gasket! Emphasis on the Gasket!
The S hose water neck condition and firmness of fit to the water tube!
Inboard suction hose condition!
All quad rings on each copper tube!
The drain plug in the first copper tube (it must be installed if so equipped)
Sea Water (raw water) pump and impeller!
The two "Thrust" surfaces of the pump housing!
H/E condition! Must be clean, no debris, no impeller pieces lodged in it from a previous broken impeller.
Exhaust manifold spent water passages! (this cannot be blocked)
Copper tube connection to the above!
And of course, the engine thermostat!

One other silly sounding tid bit of info here........ and that would be crustaceans growing in the water passages if this boat has been moored. I've removed these before as silly as that may sound to you.
So check this along with the other areas mentioned.

There are few reasons why these would not work as intended. Mostly lack of "Routine" Maintenance, IMO.

Also note that some of these components at the drive will come up and out of the water once on plane. If these parts leak air, you loose suction.

Good luck! Persistence will prevail!"
 
"Thank you guys sooooooo much,

"Thank you guys sooooooo much, So I kept telling Jeff about Eddie!!! And by the way, you are not being a A** Hole. (lol). I told Jeff, and he is now going to order all of the o-rings, and hoses, I suppose. Again, I thank you guys so much, I will get back to you, hopefully, we can get out on this this this season, lol. I am leaving this up, so they can read it tonight, after I read it to Jeff over the phone. This is a really helpful tool, for all of us that don't know much about boats, I LOVE THIS SITE!!!"
 
"Yeah i found out that to get

"Yeah i found out that to get correct answers I have to buy Rick gift cards to Red Lobster
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ROFLMAO!!!

Joke aside Rick you have helped me a lot along with El. Pescador and I give much thanks for that and couldn't ask for any better Help!!!"
 
"Well El P. doesnt have any re

"Well El P. doesnt have any red lobster's around his area and u said to save my money for 3 dollar a gal fuel lol.... However, I really would send ya an e gift card for your help if required lol..I do thank you guys a whole bunch. You guys are awesome!!!!"
 
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