Oddly specific diesel leak

[KroSha]

I have a Kelvin J2. After the last time the main diesel tanks were filled, I found a moderate sized spill on the engine room floorboards. Today, as the tanks were topped again, I paid attention to find out where it was coming from.

 

Diesel was dripping from the casing on the lower right side of the governor. Now this is a slow leak, only a small amount per min. And it doesn't occur all the time, as I put down cloths in the general vicinity after the last time to try and pinpoint it. It only seems to happen when we are being fuelled. Even when I do the daily topping of the day tank, it is either fine or so small I'm not noticing it. When the main ranks are being filled, it drips.

 

Does anyone have any ideas for an easy fix? I'm not relishing the thought of taking the governor off to re-gasket, or whatever it is that needs doing.

 

Edit to add photo.

Edited February 28, 2016 by KroSha

[BEngo]

I recognise that engine!

 

To stop the leak happening try taking out the governor filler plug ( brass plug just aft of the injector drain) when topping up the tank. Filling the tank tends to pressurizethe governor via the overflow. Taking out the filler lets the air out. The leak is usually from the small vent hole on the upper right front of the governor and it then runs down the front face to appear where you describe it.

 

If you need to, getting the governor off is a fiddle, but is just a case of undo all the linkages and fuel pipes then remove the two holding down bolts. The inside bolt is a b$gger to get a spanner on!.

 

Once off remove the gland pushers and drain out the diesel(screw at bottom, back plate) then undo the half-dozen or so bolts which hold the three sections together. The front and back plates have little cutaway slots at the joints in places, into which you can insert a suitable lever to separate the plates from the main casing.

 

There is no governor gasket. Seal the end plates with Hylomar. The bolts are sealed with lead washers, which seem to re-use OK. You will need some new packing for the two glands.

 

N

 

ETA add various bits and correct the spelling.

Edited February 29, 2016 by BEngo

[KroSha]

Thanks. I figured that it some something to do with the pressure of filling the tank. As the heating is on 24/7 at the moment, we are getting through quite a lot of diesel.

[MtB]

I recognise that engine!

 

To stop the leak happening try taking out the governor filler plug ( brass plug just aft of the injector drain) when topping up the tank. Filling the tank tends to pressurizethe governor via the overflow.

 

 

 

Hmmmm how does that happen when the tank has a vent to atmosphere?

 

But given that it does, wouldn't a simpler fix be to install the overflow as originally intended, i.e. discharging into a Teachers scotch bottle rather than going back into the tank?

[Leisure boater]

Rub a bar of soap in and around the leaking joint, that is very good at stopping diesel leaks.

[BEngo]

Hmmmm how does that happen when the tank has a vent to atmosphere?

In order to get any outward flow through the vent to atmosphere there must be a greater pressure in the tank than outside it. This pressure also nips up the overflow pipe and vents through the governor. Additionally, in this case the governor overflow is at the front of the tank, which has slight bow up trim. The vent pipe is a little further aft IIRC, so once the diesel level reaches the vent take off there is a wedge of space not served by the vent pipe- this vents through the overflow.

 

Ah Teachers leak off/overflow containers! Much effort and brain death involved in emptying new bottles to replace the ones that get broken.

 

 

Rubbing soap on the leak won't help, in this case, since the actual leak is probably out through a designed in vent hole. It only shows up as it drips off the edge of the governor.

 

 

 

N

[KroSha]

Here you can see the side of the governor, with the described drain hole. We have topped off the tank yet, but I'll post back when we do.

 

Edit: why do photos never upload the right way around?

Edited March 6, 2016 by KroSha