Volvo Penta 7.4 GL Slight Water in Oil

[mckaras]

Any suggestions on what to check and how to check where the water is coming in from? Oil is not milky at all aside from a small streak of white on the dipstick which is hardly noticeable. I'm not sure if its condensation or what it was.

Should I start with pulling the risers to see if there's any rust marks inside the manifolds?

 

[Scott Danforth]

Have you changed engine oil first? Or are you just looking at the stick?

When was the motor last ran hard to get heat in the oil?

What are the ambient temps when you last ran?

Is the boat fresh water or salt water? When was the manifold/riser/elbows last inspected

What is the SWL to riser/elbow dimension?

 

[Lou C]

And is your engine running at normal temp based on the thermostat rating? A stat that does not close all the way can cause the engine to run too cool and it won’t run hot enough to burn off condensation.

 

[mckaras]

Have you changed engine oil first? Or are you just looking at the stick?

When was the motor last ran hard to get heat in the oil?

What are the ambient temps when you last ran?

Is the boat fresh water or salt water? When was the manifold/riser/elbows last inspected

What is the SWL to riser/elbow dimension?

I did not change it myself, the previous owner changed it. I'll change it out one time to make sure. It's out of the boat so a bit difficult to get it to run up to temp on a pallet since I don't have gauges installed.

It's fresh water. I have not inspected anything as of yet. I was looking at just the stick. No oil has been drained.

 

[Bondo]

Any suggestions on what to check and how to check where the water is coming in from? Oil is not milky at all aside from a small streak of white on the dipstick which is hardly noticeable. I'm not sure if its condensation or what it was.

Should I start with pulling the risers to see if there's any rust marks inside the manifolds?

Ayuh,...... That, ^^^, is my guess,......

 

[Lou C]

I'm going to be scoping my elbows/manifolds in a few days to see how the joints look on the inside, they've been in use now for 5 seasons, I got one of those fancy endoscope cameras and used it to scope the water intake area on the outdrive where I have had barnacles growing in the past. These cameras are a boon to those of us doing our own work for the time they save, not having to take something all apart to see if there is an internal leak.
Here's a few pix of the camera and the inside of my 36 year old OMC.

A real useful tool….

I got one of those endoscope camera and esp for I/Os used in salt water they are real time savers. Today I used it to scope the water intakes of the Cobra drive where I have had an issue with barnacles growing there in the past. Found a little growth easily removed with a coat hanger wire. I’m...

forums.iboats.com

 

[Scott Danforth]

I did not change it myself, the previous owner changed it. I'll change it out one time to make sure. It's out of the boat so a bit difficult to get it to run up to temp on a pallet since I don't have gauges installed.

Never trust a prior owner

with the motor out of the boat, inspect it, and pressure test the cooling water jacket

short of on a dyno stand, running on a pallet will never get a motor up to temp without a load.

 

[mckaras]

Ayuh,...... That, ^^^, is my guess,......

Luckily dry as a bone with the risers pulled. No rust marks or signs of water intrusion there.

 

[mckaras]

Never trust a prior owner

with the motor out of the boat, inspect it, and pressure test the cooling water jacket

short of on a dyno stand, running on a pallet will never get a motor up to temp without a load.

Do you know if they sell any kits to run engines out of the boat by chance? Oil pressure, temp, water temp gauges and perhaps a control box to increase rpms?

Would it work if I increased the rpms on it with a throttle cable and shifter to get it up to temp?

 

[mckaras]

I'm going to be scoping my elbows/manifolds in a few days to see how the joints look on the inside, they've been in use now for 5 seasons, I got one of those fancy endoscope cameras and used it to scope the water intake area on the outdrive where I have had barnacles growing in the past. These cameras are a boon to those of us doing our own work for the time they save, not having to take something all apart to see if there is an internal leak.
Here's a few pix of the camera and the inside of my 36 year old OMC.

A real useful tool….

I got one of those endoscope camera and esp for I/Os used in salt water they are real time savers. Today I used it to scope the water intakes of the Cobra drive where I have had an issue with barnacles growing there in the past. Found a little growth easily removed with a coat hanger wire. I’m...

forums.iboats.com

Do you have the milwaukee one? If you can share what you use that would be great. I primarily work on cars but have had no need on them since I work on only a specific few makes and models and the issues are all the same on them. Boats I have worked on for a few years but as far as water in oil 7.4s and 8.1s and other issues specific to these models I rarely come across them so experience and knowledge is limited to 3.0s-5.7s

 

[Scott Danforth]

Do you know if they sell any kits to run engines out of the boat by chance? Oil pressure, temp, water temp gauges and perhaps a control box to increase rpms?

Would it work if I increased the rpms on it with a throttle cable and shifter to get it up to temp?

You don't need gauges to run the motor. You can jumper the harness (read your manual) or you can hot wire it .

 

[Lou C]

https://www.amazon.com/Articulating-Teslong-Industrial-Articulated-Inspect-5FT/dp/B0CJY5C9QX?ref_=ast_sto_dp

This is the one I use…

A real useful tool….

I got one of those endoscope camera and esp for I/Os used in salt water they are real time savers. Today I used it to scope the water intakes of the Cobra drive where I have had an issue with barnacles growing there in the past. Found a little growth easily removed with a coat hanger wire. I’m...

forums.iboats.com

 

[mckaras]

You don't need gauges to run the motor. You can jumper the harness (read your manual) or you can hot wire it .

I understand, I have a set up already to run engines out of water. I'm asking in regards to having that set up having a control box with gauges hooked to it so I can check temperatures and pressures. I have a rigged ignition and key to run engines all day.

 

[mckaras]

https://www.amazon.com/Articulating-Teslong-Industrial-Articulated-Inspect-5FT/dp/B0CJY5C9QX?ref_=ast_sto_dp

This is the one I use…

A real useful tool….

I got one of those endoscope camera and esp for I/Os used in salt water they are real time savers. Today I used it to scope the water intakes of the Cobra drive where I have had an issue with barnacles growing there in the past. Found a little growth easily removed with a coat hanger wire. I’m...

forums.iboats.com

Thank you sir!

 

[Grub54891]

I get some condensation on my small lake. It needs a good hard run to burn off the condensation. On Lake Superior, it does not get milky by any means. On the 340-acre lake I have to go wide open for a few laps to get it to burn off.

 

[Lou C]

If you're in freshwater especially I'd use a 160 stat if that is a concern. I use one in salt water and haven't had a problem with calcium build up in the cooling system. I actually tried a 140 stat and the engine took forever to warm up and I had some condensation not in the engine but in the exhaust system. This is yet another advantage of closed cooling. The engine can run hot enough all the time to burn off condensation, and because of the pressurized cooling system, there is no concern with localized boiling in the cylinder heads.

 

[Scott06]

I did not change it myself, the previous owner changed it. I'll change it out one time to make sure. It's out of the boat so a bit difficult to get it to run up to temp on a pallet since I don't have gauges installed.

It's fresh water. I have not inspected anything as of yet. I was looking at just the stick. No oil has been drained.

you can use a cheap gauge like this stabbed into the intake/thermostat housing or a IR gun to see temp https://www.amazon.com/Bosch-SP0F00...cphy=9007369&hvtargid=pla-2281435180738&psc=1

when running on the hose on a pallet you may need to restrict the water flow a bit to get it up to temp. Run it somewhat hot and change the oil is bets you can do but make sure the risers are not leaking back

 

[mckaras]

you can use a cheap gauge like this stabbed into the intake/thermostat housing or a IR gun to see temp https://www.amazon.com/Bosch-SP0F00...cphy=9007369&hvtargid=pla-2281435180738&psc=1

when running on the hose on a pallet you may need to restrict the water flow a bit to get it up to temp. Run it somewhat hot and change the oil is bets you can do but make sure the risers are not leaking back

I got my problem sorted out, looks like it was condensation coming in from carburetor. Looks like it had water in the fuel. Have it plugged up to non ethanol and after running checked inside the carburetor and intake and it's dry. Manifolds and Risers are still bone dry. It was hardly even noticeable on the dipstick.

Next step is to get this carburetor sent out to get cleaned, rebuilt, and flow tested.