fuel pump leak

[lost and found]

hello,

I got a mid 80's VW LT28 about a month ago. The last owner told me it ran fine with oil, even 100% although he advised 30% diesel. So I trusted him, running with 70% WVO, even though it only had a one tank system. Now the fuel pump leaks significantly after I only run about 200 kilometres.
There's been some cold days, about 10Celsius or 50 fahrenheit.
Today I disconnected the main tank and run straight from diesel just to check. It leaked more than before. In about 3 minutes (wish I had a watch) 1 litre went through although most of it must have gone back through the return to the main tank. But the pond underneath seemed bigger.

Any guesses what may be the cause and how to fix it? It seems I will have to take the pump for an expensive repair.

I have heard oil may damage the gaskets, or cold oil being more dense creates a lot of pressure inside the pump, also possibilities of glycerin buit up. Any other ideas or what seems more plausible? What can I do about this now?

 

[79jasper]

Find exactly where it's coming from. Seems I've seen people talk about a shaft seal on the pump quite a bit.
What happens is diesel is thinner than waste oils. So think of trying to pour 80-90 gear oil through a little spout at 10°F vs plain oil at 80°F.

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[lost and found]

The leak is in the grove of two metal chunks, between the distributor head and the main metal casing next to it.
I am not following you... do you mean adding 80 to 90% gear oil mixed with diesel to the fuel pump through the fuel lines? or what else otherwise? Sorry rode a bicycle for most of my life. It doesn't get colder than 50Fahrenheit here.

 

[79jasper]

No.
I'm saying WVO is thicker than diesel. So diesel is easier to find a leak point.

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[lost and found]

I know diesel is thinner than oil. Still don't understand what you meant by pour 80-90 gear oil through a little spout at 10°F vs plain oil at 80°F. I may be a bit thick about mechanics and don't quite get american jargon. I would be happy to understand what you meant. Could you try with other words?

No.
I'm saying WVO is thicker than diesel. So diesel is easier to find a leak point.

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[79jasper]

I just meant it as a comparison of WVO vs diesel viscosity.

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