MK5 Golf GTI

All Things Mk5 => How to Guides / Troubleshooting => Topic started by: rubdub on August 26, 2021, 05:22:35 pm

Title: Bad oil leak
Post by: rubdub on August 26, 2021, 05:22:35 pm
Hey lads,

So I've had an oil leak for the past year or so, wasn't super bad so was just topping up on a two weekly basis. Was having a look around and noticed oil on the oil filter housing. Didn't seem to be above the housing so presumed it was this and not the part that connects to the block.

Changed that with a new housing like this one last night, went for a spin and kept an eye on it while the car was parked for the next couple of hours.. no drips everything looks good

(https://i.postimg.cc/gJ2Yxcn3/thumb.jpg) (https://postimages.org/)

Woke up this morning to a pool of oil under the car (was also very black considering I had just changed it). Anyway presumed I had crossed the threads as I was putting it on as I had never had a pool to that size.

Started from scratch again today. Drained the rest of the oil. Put a new filter into the housing and installed. Filled with oil. Then had the car idling on the road outside the house and I notice immediatly more drips of oil coming from the sump this time.

(https://i.postimg.cc/KYw287hh/1629993425496.jpg) (https://postimages.org/)

(https://i.postimg.cc/Fzg5p2dh/1629993425486.jpg) (https://postimages.org/)

(https://i.postimg.cc/HkLD0vpC/1629993425492.jpg) (https://postimages.org/)

Thinking of just leaving it in to the garage, but would love to figure out where it might be coming from before I do/

If anyone has any thoughts on the culprit it would be much appreciated!
Title: Re: Bad oil leak
Post by: bobby_fodge on August 26, 2021, 06:53:23 pm
what does it look like where the oil filter housing is?
Title: Re: Bad oil leak
Post by: rubdub on August 26, 2021, 07:32:47 pm
This time it's dry, even the part of it above it which connects to the block.

This oil leak started pretty quickly after I had the car running and idling..
Title: Re: Bad oil leak
Post by: bobby_fodge on August 26, 2021, 07:42:18 pm
from the pics it looks like the leak start where the sump joins the block.

Is that what you see underneath the car?

I initially thought it might be oil that you'd spilt when filling the car but the oil looks like it been through the engine.

Is it still dripping?
Title: Re: Bad oil leak
Post by: rubdub on August 26, 2021, 08:23:46 pm
Yeah I didn't put it up on stands today to change the oil and filter housing, just done it on the ground as was in a bit of a rush.. so that's as far as I can get under for now. Hopefully will have time on Sunday to have a proprer look.

Seems to be still leaking, although not as much.

This one is from 6.10pm
(https://i.postimg.cc/x8vw3GKz/1630005304488.jpg) (https://postimages.org/)

This one is from just now
(https://i.postimg.cc/8kLgGGqz/1630005304480.jpg) (https://postimages.org/)

and upwards towards from where it seems to be coming from - so not sure if it's just old oil that's heating up and dripping when the ending is on... or a leak from sump or above...
(https://i.postimg.cc/vB9kG72N/1630005304468.jpg) (https://postimages.org/)

Thanks!
Title: Re: Bad oil leak
Post by: LC5F on August 27, 2021, 07:50:12 pm
That picture looking up at the block - that's been leaking there for a very long time.
Looks like its the gasket seal between the block and the oil filter/heat exchanger was weeping, changing the oil filter holder has disturbed it making it worse.
Title: Re: Bad oil leak
Post by: pudding on August 29, 2021, 01:53:02 pm
Hmmmm, those drips are nowhere near the oil filter housing.  It's all on the left side, which could either be a bad crank seal, bad cam cover gasket or a bad camshaft seal.

Worth also checking the turbo oil feed line in case that's leaking and wicking round to the side of the engine.

If oil can be seen dripping out from behind the cam belt cover, it's likely the crank or one one of the cam seals.

If it is the crank seal, that's the worst one but not that bad in parts. Around £20 for the seal with tool from Elring, £16 for the diamond washer and a fiver for the crank bolt. All are one time use.  The worst bit of the job is removing the crank bolt if you don't have a beefy impact wrench.
Title: Re: Bad oil leak
Post by: rubdub on August 29, 2021, 03:22:17 pm
Cheers lads.

Sorry I wasn't very clear on that. The oil filter housing was a second oil leak which has thankfully been taken care of now. But will check out those areas you both mentioned for the other leak.
Title: Re: Bad oil leak
Post by: pudding on August 31, 2021, 07:58:22 pm
OK cool.  Just to confirm, the last pic is behind the metal boost pipe yeah? If so, unfortunately the crank seal could be a suspect.  Not common for that one to go on these engines to be honest, but not unheard of.  Hopefully it isn't that.

If you're lucky, oil from an easier seal to fix has crept round that to that side?  Are you 100% sure you didn't tip oil past the filler neck?
Title: Re: Bad oil leak
Post by: Stupots on August 31, 2021, 08:18:36 pm
I’m gonna say it could well be the rocker cover seal. Have you got an endoscope or even your phone down the back of the rocker cover?

When some people do maintenance and have the rocker cover off they often put silicone on to refit, bad idea!

Seen multiple Golfs with this issue. They rocker seal should be fitted with no silicone (well just a spot either side of the cam journals) and replaced if damaged. People also over tightening or thread the rocker cover bolts when they have a built in spacer to set the correct gap.

Hope you find the issue soon.
Title: Re: Bad oil leak
Post by: pudding on August 31, 2021, 08:55:55 pm
Yeah, the cam cover bolts only need 7lbft.

I think the mindset of a lot of people with anything that could potentially leak is to over-tighten.
Title: Re: Bad oil leak
Post by: brian_badonde on September 04, 2021, 09:00:23 pm
When I changed my chain/tensioner my cam cover gasket was so brittle it split into separate pieces. They do harden badly over time/heat cycles and mine was definitely leaking at 110,000 miles, although not as bad as yours.

Sent from my SM-G960U using Tapatalk

Title: Re: Bad oil leak
Post by: blingsta on October 05, 2021, 10:07:28 pm
mine was in for MOT last week and we spotted a leak from bottom corner of what looked like the sump, so i gave it to my local mechanic and asked him to investigate..    it was actually from the crank seal  :scared:
so all parts ordered - new belt, tensioners, seal, waterpump etc at a cost of £180..   and £180 for labour, also changed my cam follower whist he was at it  :jumpmove:....    oh and £60 labour for DSG service...  car now feels even better to drive than before  :grin:
Title: Re: Bad oil leak
Post by: pudding on October 07, 2021, 03:17:07 pm
A leak at that end usually is a crank seal.  Ditto if it's the gearbox end.   The sump on these engines never leak from the factory.  The only time they do is when someone's done a pick up pipe job and splattered silicon everywhere like cake frosting, but not on the surfaces that matter  :grin:

Thankfully the front crank seal is an easy and cheap job.  Not so the rear one though!  Gearbox off job.  You won't be surprised to learn VW updated both seals at some point in the production cycle.  My rear seal was leaking when I last did the clutch. It had the early plastic housing, so switched it out for the newer metal one.