Events, oldest first..
( 94 Xantia 1.9Td )
1) Replace the radiator due to leak. Fill with plain tapwater while testing. System bled.
2) No water loss over three weeks.
3) Driving along the motorway, sudden loss of power. Noticed white 'smoke' coming from exhaust. Stopped at services - very high pressure in coolant. Limp home ( 8 miles ).
4) Gap of ten days - car left unused.
5) Checking car today.
Drained water - perfectly clear, no sign of contamination.
Oil filler cap shows no gunk.
Feed out from intercooler to inlet manifold shows signs of heavy oil contamination.
Feed from turbo to intercooler shows heavy signs of oil contamination.
The air filter and housing remain clean.
My original diagnosis ( when it happened ) was the head gasket. However, I now suspect that a seal in the turbo has gone, causing oil to get into the compressed side, and into the engine, leading to the smoke ( white with oily smell ), and reduced power ( contaminated air ).
I'm going to do the head gasket ( looks like the rocker gasket has gone as well ), and the timing belt & tensioner anyway, but what do you think to my turbo theory ?
I suppose the proof will be when I take the gasket off tomorrow.
Mat.
Is my diagnosis correct ?
Moderator: RichardW
The oil deposits most likely are from the crankcase/engine breather connections to the air intake after the air filter to the turbo.
The head gasket may have only blown between the water system and one of the clyinders, so where you say the coolant was under heavy pressure, points strongly to the gasket has blown. If this is the case you won't see any contamination, only possibly water in the sump oil of a small amount. So before you restart your engine it would be worth changing the oil and filter to be sure.
Have fun. [;)]
The head gasket may have only blown between the water system and one of the clyinders, so where you say the coolant was under heavy pressure, points strongly to the gasket has blown. If this is the case you won't see any contamination, only possibly water in the sump oil of a small amount. So before you restart your engine it would be worth changing the oil and filter to be sure.
Have fun. [;)]
I expect its quite easy to remove the pipe from the turbo to the intercooler - if so disconnect it, rev the engine and put a rag in the path of the air from the turbo. Any oil collected will have passed the turbo bearings and seals.
As sooty says the air intake is always dirty from crankcase fumes.
If the seals have gone then the engine would be using oil. Usually on (BX circuit for crankcase is into air filter behind filter and they tend to drop oil onto the air cleaner element.
jeremy
As sooty says the air intake is always dirty from crankcase fumes.
If the seals have gone then the engine would be using oil. Usually on (BX circuit for crankcase is into air filter behind filter and they tend to drop oil onto the air cleaner element.
jeremy
Well,
I'm well on the way to changing the head gasket. I already have the cylinder head bolts out, and I'm just disconnecting the turbo from the exhaust manifold ( forgot ! ).
I have noticed a significant amount of oil running down the outside of the exhaust pipe ( and underneath the car ).
Assuming the cylinder to the left of the car ( when sat inside ) is nr 1, these were the state of the bolts ( head not off yet ).
Blt Rear
|| O O o o
|| R D R D
Blt Front
O = Oil - Lots
o = Oil - Some
R = Light Brown 'Rusty'
D = Dry ( as new )
So it looks like it's blown in a major way !
Should get the head off one night this week - weather permitting.
Mat.
I'm well on the way to changing the head gasket. I already have the cylinder head bolts out, and I'm just disconnecting the turbo from the exhaust manifold ( forgot ! ).
I have noticed a significant amount of oil running down the outside of the exhaust pipe ( and underneath the car ).
Assuming the cylinder to the left of the car ( when sat inside ) is nr 1, these were the state of the bolts ( head not off yet ).
Blt Rear
|| O O o o
|| R D R D
Blt Front
O = Oil - Lots
o = Oil - Some
R = Light Brown 'Rusty'
D = Dry ( as new )
So it looks like it's blown in a major way !
Should get the head off one night this week - weather permitting.
Mat.
-
tomsheppard
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Your bolts look as they should, similar to those taken off my engine recently. Hich coolant pressure could and usually does mean head gasket but if the beast has run out of oil then that could be why. Oil running down the exhaust sounds ominous. Has the oil pipe to the turbo fractured? if so, does the turbo spin ok?
The sump appears to be empty, but that could be because the car is 30 degrees to the left at the moment.
The 'smoke' was white, and had a smell of oily steam [|)].
The turbo surroundings appear to be dry, and nicely bedding in with a rust crust [^]!
Why would oil on the bolts be 'normal' [?] Surely the purpose of a gasket is to stop leakage, so the fact that there is oil on the bolts would indicate oil getting out of it's normal channels ?
PS. The turbo was working fine up to, and during the smokey episode !
Mat.
The 'smoke' was white, and had a smell of oily steam [|)].
The turbo surroundings appear to be dry, and nicely bedding in with a rust crust [^]!
Why would oil on the bolts be 'normal' [?] Surely the purpose of a gasket is to stop leakage, so the fact that there is oil on the bolts would indicate oil getting out of it's normal channels ?
PS. The turbo was working fine up to, and during the smokey episode !
Mat.
The "oily smell" from the exhaust could well be antifreeze . . .
All the air pipes on my '93 XM TD12 are oily - despite the engine running normally and not consuming oil between changes - as Sooty said, most of it comes from the crankcase ventilation.
I have heard a horrendous story from my tame Citt mechanic: one of the Turbo diesel taxis he was servicing blew an oil seal on the turbo when he revved it up - the engine started to accelerate despite the trottle being released - it was running on engine oil! turning the ignition off didn't help and by the time he had the precence of mind to pull off part of the turbo air piping, the engine was nearly empty of oil, the garage was full of stinking exhaust fumes and he was deaf for several days afterwards!
//NiSk
All the air pipes on my '93 XM TD12 are oily - despite the engine running normally and not consuming oil between changes - as Sooty said, most of it comes from the crankcase ventilation.
I have heard a horrendous story from my tame Citt mechanic: one of the Turbo diesel taxis he was servicing blew an oil seal on the turbo when he revved it up - the engine started to accelerate despite the trottle being released - it was running on engine oil! turning the ignition off didn't help and by the time he had the precence of mind to pull off part of the turbo air piping, the engine was nearly empty of oil, the garage was full of stinking exhaust fumes and he was deaf for several days afterwards!
//NiSk