VR6 Intermittent Burning Oil Woes.....Page 3.

[gazareth]

you will get a very slight leak past the piston ring end gaps but that cant be helped. you may be able to measure the top ring end gap with a very then piece of wire and a vernier caliper just to make sure its not outside tolerance.

[Gti_Jamo]

I will more than likely take my chances and build it back up. Like i said barely any oil escaped past the rings. I sat an 25mm of oil in them and the had dropped to about 22mm over 3 days and had no further loss after that. No way its getting rebored as cant afford that right now. If it turns out oil is getting past the rings then will just change the bottom end.

[gazareth]

yeah a rebore is big bucks eh. maybe the 80k mileage is genuine. I mean if the head is in good order and it was a vw head gasket (showing it probably hasn't been split before). then the bottom end could be sound. did you scrape carbon of lip on bore? I find a scotchbrite and wd40 just right for doing that and cleaning piston crowns.

[Gti_Jamo]

Yeah i used exactly that to clean the lip. The pistons look mint and that without cleaning them. Only a bit of surface carbon. I dunno if i mentioned but the head has been off very recently as its been skimmed and gasket did not look bad at all.  Brand new chains also so someone had faith in it at some point recently to do the work. The guy wasnt the owner bet getting rid for his mate. He said it came out because of a 1.8t conversion and said it was a strong engine.

[gazareth]

have a good look at the cylinder walls to check for any scoring. if there is none then I would take a chance with it. I had a 2.0 audi 3a block once with 172k on it. there was a slight ridge on the bores but I stuck it in my mk2 golf anyway and it ran mint. pulled really well and wasn't bad on oil at all.

[Len]

Having a rebore to 83.5mm and am being charged £86.00
So its not big bucks!

[Gti_Jamo]

Having a rebore to 83.5mm and am being charged £86.00
So its not big bucks!

Why so much? Surely bigger pistons will be needed being 2.5mm larger or do new rings take that up? Did your bores have a lip and did you measure the wear? Looking at my bores again, with the lip being original diameter the wear isn't too bad. No scoring of the cylinder walls from what I can see and feel.

[Len]

And here was me thinking £86 was dirt cheap! Is round my way!

Only reason I am having a rebore is to increase the capacity to 2.1 litres (2092cc) with a diesel crank 95.5mm throw.

[Gti_Jamo]

And here was me thinking £86 was dirt cheap! Is round my way!

Only reason I am having a rebore is to increase the capacity to 2.1 litres (2092cc) with a diesel crank 95.5mm throw.

 

No I meant why so much material removed. But thought you were on about a vr engine.

[tshirt2k]

He's doing an ABF engine.

It might be worth re ringing the block after Honing with a flexhone. It doesn't necessarily need a rebore as rings can wear faster than the block. A bore micrometer can show you how much wear.

Flexhones are fairly cheap off eBay and you can do it with a drill and some paraffin. 

Then put some new rings in and that should give you some peace of mind.

You will have to run the engine in to bed the rings in though

My engine had a slight lip at 123k but when measured it was only 0.03mm and was well within wear limits.