Volvo Penta Water in pistons

sluggo · 08-02-2021, 10:38 AM

In my experience as an automotive mechanic of 30 years I had a volvo engine do the same thing and after days of trying to figure it out I found that the aluminum block had a casting issue and was seeping through the block and I have seen it in the aluminum heads as well. I would think that if the engine is hydro locking the water is coming in to the cylinders through one of the cooling jackets in the heads . Not saying that's the problem but a good place to check.

Woodsy · 08-02-2021, 03:20 PM

If this the motor.... I would be looking at the design of those catalyzed exhaust manifolds! Any leak at all and the motor will ingest water and possibly hydrolock!

Woodsy

Juiced06GTO · 08-02-2021, 04:26 PM

Woodsy, I'm not sure if those are the same manifolds, that looks to have a coolant reservoir on it which would suggest a closed cooling system. I am guessing the OP's motor is raw water cooled. I'm not sure what those manifolds look like, but I would think it is a different design. The only way water can get into those cylinders would be through a leaking head gasket or leaking riser manifold gasket, or a wave hit the back of the boat with enough force to flow up the exhaust system and into the cylinder. I'm not sure how else it could get in.

Is it a closed cooling system or raw water? If it is a closed system it would have coolant in it in that tank on the front of the motor in Woodsy's picture. I believe those are set up to pass the coolant through a heat exchanger that is cooled with raw water. The marina should be able to run a pressure test on the cooling system to determine where the leak is though.

Woodsy · 08-02-2021, 06:04 PM

Quote:

Originally Posted by Juiced06GTO

Woodsy, I'm not sure if those are the same manifolds, that looks to have a coolant reservoir on it which would suggest a closed cooling system. I am guessing the OP's motor is raw water cooled. I'm not sure what those manifolds look like, but I would think it is a different design. The only way water can get into those cylinders would be through a leaking head gasket or leaking riser manifold gasket, or a wave hit the back of the boat with enough force to flow up the exhaust system and into the cylinder. I'm not sure how else it could get in.

Is it a closed cooling system or raw water? If it is a closed system it would have coolant in it in that tank on the front of the motor in Woodsy's picture. I believe those are set up to pass the coolant through a heat exchanger that is cooled with raw water. The marina should be able to run a pressure test on the cooling system to determine where the leak is though.

GTO....
.
Even if it is a closed cooling system... they need to pump raw water thru the heat exchanger and that hot water gets dumped out the exhaust.

Woodsy

Juiced06GTO · 08-03-2021, 09:17 PM

Bad riser gasket then maybe, or just bad design allowing reversion up through the manifold when slowing down?

I've never had a closed cooling marine engine apart so wasn't sure what they did with the heat exchanger water.

Dave R · 08-10-2021, 10:09 AM

VP used to use exhaust flappers/water shutters in the exhaust system just downstream of where the cooling water mixes in with the exhaust gases. For some reason they stopped about 20 years ago. They were there to prevent water from coming up into the exhaust when the boat decelerates rapidly.

I would guess that your engine is a bit too low relative to the water line of the boat and water can make its way up too easily. Risers between the manifolds and elbows were a common fix for this, but some new exhaust designs don't allow for this because the manifolds and risers are one piece. I'm not sure what can be done for your boat, but you should never ever pull the throttle lever to idle while on plane, always slow down gradually unless there's an emergency.

Your starter (likely a Delco PG260M) has a planetary reduction gear set with a plastic ring gear that will fail if the engine is hydro-locked. You can usually just replace the $10 gear https://www.walmart.com/ip/New-Gear-Stationary-for-Delco-PG260M-Series-PMGR-Starters/824445923?wmlspartner=wlpa&selectedSellerId=101001368&&adid=22222222227257783475&wl0=&wl1=g&wl2=c&wl3=307316312058&wl4=aud-1308652556816

la-551611137986&wl5=9002460&wl6=&wl7=&wl8=&wl9=pla&wl10=127117920&wl11=online&wl12=824445923&veh=sem&gclid=CjwKCAjwx8iIBhBwEiwA2quaq4hRxy-Yb_YhWfZfFOVmzNYOe-RPf3DyQXYLHmkTfiFvZ6HaymQrsxoCueoQAvD_BwE&gclsrc=aw.ds to fix the starter.

Nololoco · 02-20-2022, 05:41 PM

Maddie. Did you figure out where the water was coming from?

Maddie · 02-27-2022, 03:14 PM

No. Volvo had no idea and neither did the marina service. They replaced a bunch of parts after being pulling the engine and the boat being out of service for 6 weeks in the middle of the Summer. When I finally got the boat back I put about 10 hours on the motor without any issues.

08-02-2021, 03:20 PM	#2
Woodsy Senior Member Join Date: May 2004 Location: Weirs Beach Posts: 1,966 Thanks: 80 Thanked 980 Times in 440 Posts	If this the motor.... I would be looking at the design of those catalyzed exhaust manifolds! Any leak at all and the motor will ingest water and possibly hydrolock! Woodsy Attached Images __________________ The only way to eliminate ignorant behavior is through education. You can't fix stupid.

08-10-2021, 10:09 AM	#6
Dave R Senior Member Join Date: Jul 2004 Posts: 2,985 Thanks: 246 Thanked 744 Times in 444 Posts	VP used to use exhaust flappers/water shutters in the exhaust system just downstream of where the cooling water mixes in with the exhaust gases. For some reason they stopped about 20 years ago. They were there to prevent water from coming up into the exhaust when the boat decelerates rapidly. I would guess that your engine is a bit too low relative to the water line of the boat and water can make its way up too easily. Risers between the manifolds and elbows were a common fix for this, but some new exhaust designs don't allow for this because the manifolds and risers are one piece. I'm not sure what can be done for your boat, but you should never ever pull the throttle lever to idle while on plane, always slow down gradually unless there's an emergency. Your starter (likely a Delco PG260M) has a planetary reduction gear set with a plastic ring gear that will fail if the engine is hydro-locked. You can usually just replace the $10 gear https://www.walmart.com/ip/New-Gear-Stationary-for-Delco-PG260M-Series-PMGR-Starters/824445923?wmlspartner=wlpa&selectedSellerId=101001368&&adid=22222222227257783475&wl0=&wl1=g&wl2=c&wl3=307316312058&wl4=aud-1308652556816la-551611137986&wl5=9002460&wl6=&wl7=&wl8=&wl9=pla&wl10=127117920&wl11=online&wl12=824445923&veh=sem&gclid=CjwKCAjwx8iIBhBwEiwA2quaq4hRxy-Yb_YhWfZfFOVmzNYOe-RPf3DyQXYLHmkTfiFvZ6HaymQrsxoCueoQAvD_BwE&gclsrc=aw.ds to fix the starter.

02-20-2022, 05:41 PM	#7
Nololoco Junior Member Join Date: Feb 2022 Posts: 1 Thanks: 0 Thanked 0 Times in 0 Posts	Figure it out? Maddie. Did you figure out where the water was coming from?

08-02-2021, 10:38 AM	#1
sluggo Senior Member Join Date: Nov 2010 Posts: 170 Thanks: 13 Thanked 70 Times in 43 Posts	In my experience as an automotive mechanic of 30 years I had a volvo engine do the same thing and after days of trying to figure it out I found that the aluminum block had a casting issue and was seeping through the block and I have seen it in the aluminum heads as well. I would think that if the engine is hydro locking the water is coming in to the cylinders through one of the cooling jackets in the heads . Not saying that's the problem but a good place to check.

The Following User Says Thank You to sluggo For This Useful Post:
stingray (08-10-2021)

08-02-2021, 04:26 PM	#3
Juiced06GTO Senior Member Join Date: Aug 2017 Posts: 213 Thanks: 9 Thanked 84 Times in 49 Posts	Woodsy, I'm not sure if those are the same manifolds, that looks to have a coolant reservoir on it which would suggest a closed cooling system. I am guessing the OP's motor is raw water cooled. I'm not sure what those manifolds look like, but I would think it is a different design. The only way water can get into those cylinders would be through a leaking head gasket or leaking riser manifold gasket, or a wave hit the back of the boat with enough force to flow up the exhaust system and into the cylinder. I'm not sure how else it could get in. Is it a closed cooling system or raw water? If it is a closed system it would have coolant in it in that tank on the front of the motor in Woodsy's picture. I believe those are set up to pass the coolant through a heat exchanger that is cooled with raw water. The marina should be able to run a pressure test on the cooling system to determine where the leak is though.

The Following User Says Thank You to Juiced06GTO For This Useful Post:
VitaBene (08-02-2021)

The Following User Says Thank You to Woodsy For This Useful Post:
Juiced06GTO (08-03-2021)

08-03-2021, 09:17 PM	#5
Juiced06GTO Senior Member Join Date: Aug 2017 Posts: 213 Thanks: 9 Thanked 84 Times in 49 Posts	Bad riser gasket then maybe, or just bad design allowing reversion up through the manifold when slowing down? I've never had a closed cooling marine engine apart so wasn't sure what they did with the heat exchanger water.

02-27-2022, 03:14 PM	#8
Maddie Junior Member Join Date: Jul 2020 Posts: 9 Thanks: 1 Thanked 0 Times in 0 Posts	No. Volvo had no idea and neither did the marina service. They replaced a bunch of parts after being pulling the engine and the boat being out of service for 6 weeks in the middle of the Summer. When I finally got the boat back I put about 10 hours on the motor without any issues.