New need help!

Got a good deal on a 1985 bayliner carpi 19". $2000 cash. I will attach pics of boat and engine. I believe it is a volvo aq125, correct me if im wrong. With a volvo 270 outdrive. When i bought the boat i noticed antifreeze leaving from behind the heat exchanger. We couldn't locate the exact place it was coming from. The starts and runs great. so i could not pass up the good deal despite the coolant leak. I was going to try and locate the leak myself but her is my problem. Using earmuffs around the water intake on the drive with a water hose I cant see water coming up through to the heat exchanger with the cap off. At first i thought maybe it had to worm up for the thermostat to open but after it got up to about 190 i didn't want to run it any longer. Am i doing something wrong? How hot should l let the oil temp get with the ear muffs? Could the thermostat be stuck? I don't even know if the lake water side has a thermostat or is just the antifreeze side? Anyway before i locate the leak i at least want to know how the heck to run this thing with a hose. Also i tried filling up a rubber made tote with water and submerged the drive and still no water flow to the motor.

Re: New need help!

Your engine has two cooling systems. The closed side with the antifreeze, circulates through the engine and the heat exchanger like in a car and the radiator.
BUT, in a boat, there is no air flow, so water is used in the heat exchanger to cool the antifreeze. The raw water system basically replaces the air across the radiator.

So, if you have an antifreeze leak, you need to drain the coolant, then pressure test the system with a radiator tester just like on a car and see where the leaks are. Since it's air, a spray bottle of soapy water easily finds the air leak because it blows bubbles.

Re: New need help!

Why cant i see raw water going to the radiator from the water hose?

Re: New need help!

If the raw water is pumping, you should be able to see it in the stainer housing. The heat exchanger is not in the tank that says no step, its in the bottom of the assembly right next to it. The strainer housing I mentioned is above the heat exchanger. If you pull the cap of the strainer housing with the engine running, water should spray out all over the place.
I would start by pulling the cover off the raw water pump and check/replace the impeller. It should be replaced every 1-2 years. Have a look at these parts diagrams.

heat exchanger and strainer
Heat Exchanger With Installation Components: A AQ140A : A - 7742840 - Volvo Penta

Raw water pump
Sea Water Pump: 828026 - 7742840 - Volvo Penta

Also, if you're running on muffs, be sure to plug the hole in the bottom of the outdrive and get a set of good fitting muffs, like these.
Volvo Motor Flusher - Seasense 50073749 - iboats

Re: New need help!

When you hook up the muffs,there is a 1/2in.hole on the bottom of the drive.It needs to be plugged.
I usually duct tape the muffs in place.That way they are sure to work.
Next the pump inside the boat.It's got 4 screws and the cover comes off.
The impeller should come out.You might need to pry the impeller out,just be careful not to damage the edges of the pump.
If the impeller comes out and any blades are missing,find them.

Re: New need help!

At first i thought maybe it had to worm up for the thermostat to open but after it got up to about 190 i didn't want to run it any longer.

Click to expand...

The thermostat in that engine is supposed to start opening at 180? and is fully open at 198?.
Typically those engines run at 190? to 195? so you may be shutting it off just before the thermostat opens and the water starts circulating.

Yes, the Volvo 4 Cyl. OHC engines run warmer than any other marine IO engines.

Re: New need help!

Im not sure if i have a 125 a or b. is it the same impeler for both? Is the a way to tell if i have an A or B.

Re: New need help!

Look all over the port side of the engine. There should be a brass tag somewhere on it with the model number on it.

Yes the thermostat is the same for A or B

Re: New need help!

Not thermostat. Is the impeller interchangable?

Re: New need help!

Just look them both up and compare! Yes, they have the same part number: Impeller Kit 875575

I thought this might help:

Re: New need help!

Ok so here is the deal. I replaced the raw water impeller. Using my universal muffs that don?t seal very well around the intake holes I started it and could not get it to pump. So then I filled my tub up with water and submerged the drive in there. Still no pumping. Then I put the muffs on under the water with the tub and it worked. I checked for air leaks all through the system and it all seems air tight. So my theory is that with the loose fitting ear muffs or tub alone there is not enough suction to pull water all the way up from that low, but with the muffs on and submerged in water there?s enough force from the hose to help push it up. So with the boat actually in the lake with the transom a lot further down in the water the pump will not have to pull as hard and far and should pump water.Right?
Now as far as my other problem I had was a small radiator leak. Well it is not leaking any more. The boat set for a couple years not being started very often so could the seal just have reset itself after being ran by me a few times and warming up to temp? The leak was somewhere behind the cam pully.
If im right about these two things then looks like she is ready for the water.

Re: New need help!

Do us all a favor and take it easy the first time out. Just because its pumping now with muffs and the tub, doesn't mean it won't overheat under load. Don't load up the family for a full day on the lake for your first trip. Take it out with a buddy and see what it does. Stay close to the landing until it comes up to operating temp, 190ish, and make sure it stays there at idle and WOT.

And let us know how it goes!

Good Luck!

Re: New need help!

I unscrewed the radiator cap and when it let air in it started to leak again. :grumpy: At least i know the cap has a good seal.
I have located the exact place of the leak. It looks like a seal or gasket on a pipe coming from the heat exchanger to the block. Its right behind the pulley in the pics i will attach. Now i need to know what this seal is, where to get it and what to remove to get to it. It looks more like a rubber gasket. Would high temp RTV be a good substitute for this. Or do i need to order the right seal? Is there anything else i need to replaced while im in there or is this pretty east to get to? Thanks

Re: New need help!

to me it looks like it goes into the circulation pump...But I'm not sure...

#31 in this link?
Cooling System, Induction- And Exhaust Manifold: A AQ140A : A - 7742840 - Volvo Penta

Re: New need help!

Yes thats it. Is there any other seals i will need to replace while im in there like a seal set i could order? Thanks

Re: New need help!

No set, but here's a list:

Cooling System, Induction- And Exhaust Manifold: A AQ140A : A - 7742840 - Volvo Penta

#31 x 1 WP to head - 1336255
#40 x 4 HExchanger fittings - 430020
#3 x 2 raw water pump - 831622
#50 x 1 exchanger to t-stat - 975672

Heat Exchanger With Installation Components: A AQ140A : A - 7742840 - Volvo Penta

#13 x 1 elbow to strainer - 955995
#16x 1 pipe to elbow - 418412

This would be a good time to change your timing belt too, as you'll have it mostly exposed when doing this (still have the raw water pump and timing cover in the way).