Oil cooler leaking
Discussion
Car is Peugeot 106
Can someone explain how the oil cooler works above, specifically how the oil goes back into the engine. (The cooler is the shiny thing at the front of the block)
The pipes have coolant in them, so I can see that the oil passes through the middle, into the filter. But how does it get back into the engine?
This part is leaking (slightly) but persistently, and no amount of new seals, new cooler or gasket maker will stop it. So am wondering if it’s something else like a blockage or similar.
It takes around 3 mins from cold to start dripping oil from the bottom of the cooler.
Tia
This is what is behind the cooler. Oil comes out do the connector
.
Can someone explain how the oil cooler works above, specifically how the oil goes back into the engine. (The cooler is the shiny thing at the front of the block)
The pipes have coolant in them, so I can see that the oil passes through the middle, into the filter. But how does it get back into the engine?
This part is leaking (slightly) but persistently, and no amount of new seals, new cooler or gasket maker will stop it. So am wondering if it’s something else like a blockage or similar.
It takes around 3 mins from cold to start dripping oil from the bottom of the cooler.
Tia
This is what is behind the cooler. Oil comes out do the connector
.
Edited by Dynion Araf Uchaf on Monday 9th October 13:31
Oil flows out of the middle of an oil filter, the feed into the filter is through the outer ring of holes, so the feed comes out of the engine through (in your top picture) the square hole set at about 8 o'clock relative to the centre threaded boss, there may be other holes not visible from that angle.
If you have oil dripping off the bottom of the oil cooler it is either;
1. The seal, cooler to block.
2. The seal, cooler to filter ie the oil filter seal.
3. The cooler itself split or faulty weld.
4. The oil pressure switch/gauge take-off above it... I can see quite a few possible sources of leaks there!
You need to get it all clean and dry (with an evaporating cleaner eg Brake Cleaner) and observe it from start-up.
If you have oil dripping off the bottom of the oil cooler it is either;
1. The seal, cooler to block.
2. The seal, cooler to filter ie the oil filter seal.
3. The cooler itself split or faulty weld.
4. The oil pressure switch/gauge take-off above it... I can see quite a few possible sources of leaks there!
You need to get it all clean and dry (with an evaporating cleaner eg Brake Cleaner) and observe it from start-up.
TwinKam said:
Oil flows out of the middle of an oil filter, the feed into the filter is through the outer ring of holes, so the feed comes out of the engine through (in your top picture) the square hole set at about 8 o'clock relative to the centre threaded boss, there may be other holes not visible from that angle.
If you have oil dripping off the bottom of the oil cooler it is either;
1. The seal, cooler to block.
2. The seal, cooler to filter ie the oil filter seal.
3. The cooler itself split or faulty weld.
4. The oil pressure switch/gauge take-off above it... I can see quite a few possible sources of leaks there!
You need to get it all clean and dry (with an evaporating cleaner eg Brake Cleaner) and observe it from start-up.
thanks!If you have oil dripping off the bottom of the oil cooler it is either;
1. The seal, cooler to block.
2. The seal, cooler to filter ie the oil filter seal.
3. The cooler itself split or faulty weld.
4. The oil pressure switch/gauge take-off above it... I can see quite a few possible sources of leaks there!
You need to get it all clean and dry (with an evaporating cleaner eg Brake Cleaner) and observe it from start-up.
1) new seal, cleaned block, still leaks
2) not that, oil leak is from engine side not filter side
3) I'm on my second cooler, surely lightening can't strike twice?
4) maybe, I have checked it quite thoroughly though.
Still not sure how the oil comes out of the engine in to the filter, from that position. I can see the 8 o clock things you are talking about, but how does the oil get in there? It must come from the engine, but I can't see how.
In the second pic, on the engine block, there will be a port (hole) in that doughnut shaped recess around the central threaded boss.
On the back face of the cooler there SHOULD be ports similar to the one seen on the front, to allow oil into the cooler. If not, you're in trouble! ...as no oil will have passed that point.
Post up pics of the front and rear of that cooler. Have you still got the original cooler to compare?
On the back face of the cooler there SHOULD be ports similar to the one seen on the front, to allow oil into the cooler. If not, you're in trouble! ...as no oil will have passed that point.
Post up pics of the front and rear of that cooler. Have you still got the original cooler to compare?
dhutch said:
Dynion Araf Uchaf said:
Pics as requested. This is the one in the first pic. Currently I have replaced it with a second hand OE part of unknown mileage
Yeah, might be the old one that's come off, but this side looks mullered?Given the weather, cap the coolest pipes off and carry on?
dhutch said:
TwinKam said:
And that will cure his oil leak?
It'll stop oil getting into the coolant, and coolant into the oil, which is typically the issue with these things.You are however right, that the oil leak will technically remain, although the OP states it is a very slight leak.
and please tell me that beaten up Modine style cooler was not fitted to the engine at time of fault 
because its f
ked OP'er dhutch said:
TwinKam said:
And that will cure his oil leak?
It'll stop oil getting into the coolant, and coolant into the oil, which is typically the issue with these things.You are however right, that the oil leak will technically remain, although the OP states it is a very slight leak.
OP, the battered cooler that you've shown us is not the one you're using, right? It's leaking with the new(er) replacement too? So how are you sealing the cooler to the block, show us that seal, you mention 'gasket maker'... you're not expecting a liquid sealant that to seal the cooler to the block are you?... it should be a rubber O-ring type, similar to the oil filter ring.
sorry for the late replies, been OOO.
Anyway, the pic of the cooler, is the old one, no longer on the car ( although it was new at point of fitting (as shown in pic).
I bought a replacement used OEM cooler, which is now on the car, but before fitting it, I used the old ( new cooler) for some tightening practice as it felt that maybe it needed all the torques.
Any way, it transpires that the leak isn't actually coming from the cooler, but from the oil pressure take off brass fitting above. Essentially I used a rubber seal to reposition the where the take off connector pipe ended up, as standard it ended up facing away from the oil pressure tube. The oil drips BEHIND the cooler, where it build a small puddle before dripping around the side but behind the cooler and former a droplet at the bottom of the cooler, thus fooling me into thinking it was the cooler.
Fixing that has been a PITA, as I have had to use a lathe to get it all to fit included annealed copper washers so that it is both oil tight and facing the right way.
With a bit of luck it'll fixed tonight.
As ever, PISTONHEADS comes up trumps as some of the things suggested to look at, caused me to have an epiphany and actually diagnose it properly.
Anyway, the pic of the cooler, is the old one, no longer on the car ( although it was new at point of fitting (as shown in pic).
I bought a replacement used OEM cooler, which is now on the car, but before fitting it, I used the old ( new cooler) for some tightening practice as it felt that maybe it needed all the torques.
Any way, it transpires that the leak isn't actually coming from the cooler, but from the oil pressure take off brass fitting above. Essentially I used a rubber seal to reposition the where the take off connector pipe ended up, as standard it ended up facing away from the oil pressure tube. The oil drips BEHIND the cooler, where it build a small puddle before dripping around the side but behind the cooler and former a droplet at the bottom of the cooler, thus fooling me into thinking it was the cooler.
Fixing that has been a PITA, as I have had to use a lathe to get it all to fit included annealed copper washers so that it is both oil tight and facing the right way.
With a bit of luck it'll fixed tonight.
As ever, PISTONHEADS comes up trumps as some of the things suggested to look at, caused me to have an epiphany and actually diagnose it properly.
Edited by Dynion Araf Uchaf on Tuesday 10th October 17:20
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