Volvo Penta 2003 T sump filling with diesel.

[Thulani]

Hi there, I just serviced my motor for the first time. I filled the oil to halfway up the dipstick, then used the motor for about 4 hours. On rechecking g oil level, it is now up to the top level on dipstick. I suspect that it is diesel as there is no sign of coolant.
Can anyone advise if this is caused by injectors, and if so, what is the best way to repair?
Any advice much appreciated.

[sailormed]

You just filled for the first time. When did you check oil level after filling? Can it be that you checked to early and that all the new oil had not yet found its way from the top to the sump?

[undercutter]

Originally Posted by Thulani

Hi there, I just serviced my motor for the first time. I filled the oil to halfway up the dipstick, then used the motor for about 4 hours. On rechecking g oil level, it is now up to the top level on dipstick. I suspect that it is diesel as there is no sign of coolant.
Can anyone advise if this is caused by injectors, and if so, what is the best way to repair?
Any advice much appreciated.

Lift pump diaphram?

[Thulani]

I checked the oil the next day before using the motor.

[Thulani]

Please explain re lift pump diaphram?

[undercutter]

Originally Posted by Thulani

Please explain re lift pump diaphram?

If you have a mechanical lift pump and not electric then it is driven by the camshaft. If the diaphragm ruptures then it will allow fuel into the block filling the sump. If it is in fact diesel fuel filling the sump than this is your problem.

[Pete7]

Originally Posted by Thulani

Please explain re lift pump diaphram?

I the following pictures I have shown the lift pump and its location on the engine. It operates on a cam on the cam shaft and pumps fuel from the fuel filter on the front of the engine to the fuel injection pumps, you have 3 FIPs on this engine just to be different.

The new pumps are sealed and have a flat top to them. The older model pumps have a cone top with a nut which allows them to be dis-assembled.

If the pump is original, then it could be 30 years old and leaking diesel from the pump into the engine via the slot which a lever on the pump runs on the cam shaft in the engine block. I replaced our pump a couple of years ago, whilst it worked well, the age thing had me worried, rubber diaphrams don't last for ever. So it wouldn't hurt to replace the pump ($100) this may not be the cause of the problem however.

Pete

[Thulani]

Are spares available for lift pump?

[undercutter]

depending on how much oil is in the sump the difference in the readings could be just the difference between the temperature of the oil between hot and cold. Obviously it will expand when hot and be higher on the dipstick.

Once the oil is cool I would suggest that you check it again to see where the cold level is.

If that reading is still high, drain some out to the lower level and run the engine again to see if it fills up again. Make sure you make a note of the coolant level as well while it is cold just to make sure that it is in fact not coolant but as you are probably aware the oil would be frothy if it was a coolant leak.

Once you have confirmed that the oil is in fact filling with diesel then change the lift pump. Or as Pete suggests do it now if you think it is original from 2003.

The only other place that I believe that diesel can get into the block would be through the injector pump. Let's hope that this is not the case.

Did you just buy the boat?

[Thulani]

I bought the boat in July 2017 and we sailed/ motored from the marina that boat was at to current home port, which was just over 1000 nautical miles. The fresh water pump had to be repaired as it was leaking and the oil level was fine. I serviced the motor now as part of my maintenance schedule. This is where I noticed that the oil level was up.

[Thulani]

Is it a complicated job to replace the pump?

[Pete7]

Yes they are readily available and should be about $80 or £80 in the UK.

https://www.ebay.co.uk/i/28188547047...9031424&crdt=0

Easy enough to fit, don't loose the sealing washers on the banjos (pipe fittings) and it is a bit of a stretch to make the old pipes fit the new pump but it can be done.

You must close off the fuel tank or it will drain constantly also any return lines need to be closed off or the diesel will back flow and pour all over you as you change the pump. Top tip, buy a box of disposable nappies and put them down under the engine because diesel is going to go everywhere when you change the pump, been there got the t shirt.

Pete

[Pete7]

However, it might not be the fuel pump, so do top the engine up to the level of the dipstick when the engine is cold. Then check it religiously every time you use the engine for a couple of weeks.

Pete

[Thulani]

Thanks guys. Planning on going sailing tomorrow. Will first check oil level. If it's high, will drain to the low level, then check again when we get back.
Will also mark coolant level just in case.
Will post later tomorrow and give the low down.

[stormalong]

If it is diesel fuel your oil will be much thinner than normal oil. Check this first. If the oil does not look and feel thinner you may have no problem at all. It may also smell like diesel fuel.

If you do have diesel in your sump fix the problem and change your oil and filter before running the engine again.

This can be a dangerous situation. If the oil gets too high the engine can start burning the lubricating oil and you will have a run away engine that you will have a hard time stopping.

How to stop a run away engine is another topic. But you do not want to be in that situation.