gotta oil leak & wanna put thinner oil in-should i?

[martint]

ive got a slight oil leak at the crankshaft oil seal.
i changed my engine oil with comma 10-40 semi synth & now my fuel consumptions went down a few mpg.
im thinkin of changing oil to 5-40 fully synth but am wondering if the leak will get a lot worse wi the thinner oil.
what do you lot think?

[Welly]

Definitely not, 10W/40 semi-syn is perfect for the HDi and adding a thinner fully-syn might loosen deposits in the system.

Get yourself some Fuchs/Silkolene XTR 10w/40 semi-syn as this performs like a fully-syn anyway and is not that expensive.

[Bailes1992]

Get some Forte Seal conditioner, worked wonders on my Focus with leaking valve stems. Gone from using 1litre every 1000 miles to doing a litre every 2-3k. Going to give it another dose soon when I do my oil change.

It works y feeding ruer seals causing them to swell, unlike most other things that just thicken the oil

[jasper5]

How about something revolutionary?

Replace the faulty seal and fix the oil leak

[Doggy]

Now there's a radical solution!

I'd agree with jasper 110%, at least for a 'front' oil seal, think I might dither for a while if it was the gearbox end.....

[bytecode]

How about something revolutionary?

Replace the faulty seal and fix the oil leak

I agree with this; the whole reason that I am in the middle of replacing the engine on my MG MGF is because it ran out of oil (although HOW/Where from I do not know) and it threw a con-rod;


(Note how the crank bearing shell has fused into the conrod itself, it should be smooth and whole, the conrod is chipped and broken, bent, missing bits and obviously went "molten")

blowing a hole through the side of the engine block.
Yeah I know, K-series 1.8 engines are exceedingly temperamental, and some people get away with oil leaks for years on more robust powerplants, but lubrication is important for our engines - and I'm really regretting not realising that there was a problem.
It scared the life out of me when it exploded, BANG-FLASH-Cabin full of SMOKE, Dead car. :'(

[lozz]

ive never seen a k-series do that mate,
iknow there prone for Hg failiure but other than that icarnt fault them,

Ran out of oil, cam shaft seals perhaps,
ive seen the 75s suffer with disapearing oil and its been the seals gone,

[bytecode]

ive never seen a k-series do that mate,
iknow there prone for Hg failiure but other than that icarnt fault them,

Ran out of oil, cam shaft seals perhaps,
ive seen the 75s suffer with disapearing oil and its been the seals gone,

Yeah, this one was interesting there was a leak from the water pump, leading to a HGF during the (presumably)same journey.
I took the car to a garage for a Headgasket job, they had the head skimmed, fitted the uprated landrover gasket, new oil seals etc and it seemed fine.
Then it developed an oil leak from the (replacement) exhaust cam oil seal (timing side) a few weeks later, so I took it back for a replacement seal.

A few weeks later, the engine started making tappety-tappety sounds, I checked the coolant - it was fine, checked the dipstick, no oil. Added what little oil I had to get it home. I drove gently but the oil temp soared. I added more oil, tapping sound remained.
Drove it to the garage and it exploded on the way.

The only odd things are:
1) The oil after the Head Gasket job was perfectly clear, as in, no "honey-brown" colour at all, it was just thin and clear
2) There was no sign of an oil leak after having the oil seal replaced, and I regularly checked oil and coolant levels after both failures, all seemed fine until the day of the tappety-tappety sound...

Anyhow, I don't really want to hijack the O.P.'s thread... (Sorry martint)