Crank seal or hockey stick leak

[blandy 29]

Had my car on the dyno yesterday to run in and map a newly built engine. Did around a hours running in with break in oil. We noticed a small puddle of oil forming above the starter motor. The engines dry all top end and would appear the oil is being thrown from the flywheel and accumulating where the fan etc wasn’t hitting on the dyno. 

 

Bearing in mind this only happened when under load and hot my first assumption was crank seal.. could the hockey sticks be the culprit also or would that tend to be just lower down? 

 

I’ve also had suggested the break in oil can cause leaks as so thin so could be that also - has anyone else had this as I’m not convinced. Going to pull the box off at weekend to investigate just want to get any more bits if any other suggestions before the weekend 

[Tom Fenton 1,541]

My experience is that oil rarely travels up hill. If its the crank seal or hockey sticks then I'd expect it to be wet/dripping from below that area. Certainly I'd clean it down and run it again before ripping it to pieces.

[blandy 29]

i believe its being flung off the flywheel as bone dry all up the top end literally not a drop as checked usual cam covers etc and accumulating around top of the bell housing area 

 

Ill jack it up and run it without a massive fan in front of it which will hopefully help diagnosis  

[petert 586]

I broke a hockey stick seal once during installation. It leaked oil annoyingly and couldn't be confirmed until I pulled the rear cap off.

[B1ack_Mi16 67]

I think I've got a hockey-stick seal leak on all my 3 engines... I don't seem to be able to overhaul these XU engines and get them sealed.

 

But I agree, I've never seen the oil be slung upwards, neither when the crank-seal have been leaking or if the hockey seal is leaking, seem just to come seeping down to the sump from the bearing cap.

[blandy 29]

Cant think to where else it could be from to end up on top of the bell hosing by the starter .. i.e almost the furthest point away from any engine oil 

ive crudely drawn in red in the pic 

 

Has anyone else had issues with running in oil as has been suggested it could be as the oil is so thin? 

[DamirGTI 342]

Chased something similar few years ago , it was leaking oil return core plug :

 

 

 

D

 

[blandy 29]

Hope not on a new build but anything’s possible.. car doesn’t live at home so will clean up on sat and start from scratch without dyno fan stuck in front of it blowing everything all over the place 

[welshpug 1,657]

there's a pressurised oil gallery just behind the starter, would either have a bung or a pressure switch in it, theres also oil breathers in the corner behind the starter.

[Roeland_Vester 5]

I had a hockey stick seal leak, as I ripped off the top of the hockey stick while installing it. It didn't leak at idle, but at elevated revs it emitted a steady drip. Wasn't flung up by the flywheel or anything. 

[blandy 29]

1 hour ago, welshpug said:

there's a pressurised oil gallery just behind the starter, would either have a bung or a pressure switch in it, theres also oil breathers in the corner behind the starter.

Thanks I’ll have a look there as well hoping it’s something small and silly as don’t want to be taking the box off if I can help it.. I run the cams in at 2.5-3k for 20mins and not a single drop..  only noticed the oil sitting up there when on the dyno after about half hour or so but with the fan shoved in front it’s blown all over the place so just hope I can replicate it stationary 

[blandy 29]

Had a good look today. Everywhere visible was dry and no oil from anywhere in sight up top but underneath clearly damp around the gearbox to engine joint, so got on and Pulled the gearbox off. Surprisingly not to oily so pulled off the clutch and flywheel. 

 

Core plugs and blanking plug nice and dry along with the hockey seals looking dry... a tiny pool of oil sitting along the bottom of the crank seal though on the lip of the block - possibly fitted in 2 far? As measured around 2-2.8mm in with digital vernier. I still have my old engine which I measured which the seal was sat in closer to 1-1.5mm 

[blandy 29]

Was all happy run it up to find a fine leak strait away again.. stripped strait down and barely anything to see but definitely leaking oil can’t understand how or why though 

[Ozymandis 97]

Check your breather systems clear, and the crank case isnt pressurising?

If its the crank seal, then either the seal lip is damaged or the oil seal land on the crank is damaged.

When you built up the engine did you check the crank, rear bosses often have a wear groove which can lead to a leak?

 

Also the depth of fitting isn`t that crucial unless you have a wear groove, I have overcome this wear on various shafts by fitting a different width seal so it runs on an undamaged part of the seal land, or fitting the seal at a different depth to achieve the same.

 

Its a common diameter seal available in several depths, materials and configurations from bearing places eg simply bearings on the web.  The seals spec changed through the model runs, early ones were a deeper seal, PSA`s cheese paring team re-specced it to a cheaper shallower seal in later engines.

[blandy 29]

Both the crank and the bearing caps etc look and feel fine. I did have a mare getting it in as I didn’t have the tool and pushed the first one in way to far so shot to gsf and picked up a replacement which was a cheapo make. 

 

My my thoughts were it’s not in far enough as been measuring closely and dedicatedly not square sitting further in at the top than the bottom. As is cleaned throughly yesterday everything was dry so must be the seal. 

 

Breather seems fine though is the anyway to test better? 

 

I have noticed iced a tiny nick in the seal so hoping between this and the fact it’s probably not in far enough maybe the issue it’s a 88mm diesel crank which I believe uses same seal as original?

 

I have a Payen seal and a fitting tool on order 

 

 

 

 

[Ozymandis 97]

I think the XU engines,diesel and petrol, all have same size boss and seal diameter.

 

It looks damaged to me.

 

Change your fitting method , wrap a piece of thin plastic sheet (eg cut from a clear plastic packet or something)  around the boss, that will protct the lips a bit, you obviously damaged the lip last time.

 

Make up a tubular drift , get another seal and have another go, dont be too bothered by exact depth, so long as it runs on an undamaged bit of the seal land you will be fine.

 

A deeper seal is easier to fit square than a shallow one,  so long as it`s  square by eye your fine.

[blandy 29]

I’ve ordered a seal installer as struggled to get it started which I think is the issue. 

Appreciate the advice will give it a go 

[blandy 29]

I’ve had a new seal arrive along with a installer - didn’t want to risk pulling the box off again for the price of a tool. 

 

With the crank seal is it a dry fit item or lube to aid fitting? 

[Ozymandis 97]

Use some "fat", regular lithium grease is what I always use.

[petert 586]

I use heaps of engine oil and a leather working modelling tool (strange but true) to help ease the lip over. I then have a lump of aluminium, turned to the appropriate diameters and depth, which sets the seal square to the crank at the correct depth.

[blandy 29]

thanks both sides of the seal or just on the internal? 

 

The tool i have is a proper pug tool so should be spot on - even puts to right depth 

[blandy 29]

Also I’ve just had the other seal land that I ordered a week ago. 

 

I know have a febi seal and a genuine pug seal the pug item has the spring inside the lip yet the febi item appears to be a lot stiffer than the Peugeot item and more importantly has no spring...

 

which would you fit? 

[DamirGTI 342]

Funny thing i just got the Febi crank seal delivered today ! 

 

It's made by "Kaco" (some German firm as it appears) , mine has the spring , and you definitely need one with the spring as it'll be of no use without the spring . Return it back and ask for another one with the spring fitted , as it's a fault part being packed without the spring .

 

Dunno about the quality of the seal itself , never tried Febi seals yet , i used to fit OE crank seal , aftermarket - Payen or Erling (Goetze too , it's an Payen made seal repacked in a Goetze package)

 

D

Edited September 20, 2018 by DamirGTI

[blandy 29]

I’ve done some digging today as this leak is seriously bugging me lol. The febi seal I have is a ptfe type seal as opposed to a dynamic seal which is the original fit. The ptfe part is apparently why it doesn’t have a spring inside and has a totally different fitting procedure in the fact that there is no oil etc to be used on fitting as is to be fitted 100% dry who would of thought a seal would be so difficult now intriguied as cannot remember what I fitted at weekend as to what type as this could possibly be some of my issue 

 

 

 

[DamirGTI 342]

Interesting , which part number is on that particular seal ?

 

D