Technical MK1 turbo issues

[oldskoolmk1unoturbo]

My mk1 uno turbo is drinking oil and miss fireing at top end, only happens in 5th gear after 5000rpm,

it only smokes when you boost it in 1st gear which is blue oil smoke, there is no smoke from start up from cold or even when starting and the engine is hot.

how ever when your in traffic and the engine is hot when you pull off it does cough blue oil smoke out,

it loses no water and the oil has not mixed,

I did a compression test today and all four cylinders were approx 140PSI.

anyone have an idea to the problem?


hope i can sort the problem out cause its going to be for sale soon as i am going to need a Van for work

 

[Peterg]

Sounds like your piston rings are done in letting oil by and burning it up.
When the engine heats up it expands reducing the blow by.
I was always told blue smoke means turbo is knackered too I am afraid.
Pete

 

[oldskoolmk1unoturbo]

i took two of the boost hoses off to get to the spark plugs to do a compression test and the inside of the hoses had quite a lot of oil in them,

My guess is the turbo oil seals are gone.

surely if the piston rings were worn wouldnt the cylinders be low on compression?

 

[distortionrockets]

niiice, i want
price?

 

[oldskoolmk1unoturbo]

sorry mate its not forsale yet,

newton abbot, I've heard of that, where abouts is that?

 

[Peterg]

Your right sorry missed that in your initial thead. Oil seals on the turbo def sound gone. I am sure when it turns Kiwi time Alex will give you the best advice on this.
Pete

 

[alexGS]

Peterg,
A big Kiwi good-morning to you!
Sorry to let the side down, but I don't know what I'd do next with the burning oil problem It sounds like turbo seals to me, but I haven't enough experience of that fault to say for sure. What I would do is to get hold of another known-good turbocharger and try fitting it. Probably quite a number of standard turbos for sale (after upgrades etc.) Pretty expensive, but probably cheaper than having a unit rebuilt.

Incidentally the compression figures are OK if all four even, but I think they're a bit on the low side. Can someone please check in a Haynes manual (I don't have mine handy) for the quoted pressure? The engine may benefit from new rings. But, the description of when the smoke occurs doesn't sound to me as though the rings are worn out (if they were, there would be smoke pretty much all the time, accelerating in any gear, as well as when idling).

I think I would sell the car as it is, and let the new owner rebuild an engine + turbo to go with that wonderful bodyshell. You have to ask yourself: how much will fixing that fault add to its value?

Alternatively keep waiting for an answer, you'll probably have a better one here soon

-Alex

 

[oldskoolmk1unoturbo]

could the oil coming from the turbo cause the miss fire?

the spark plugs were quite oily

 

[Peterg]

Yes the turbo blows into the combustion chamber so if oil is leaking it would deposit it here and possibly foul the plugs.
Not sure about your turbo do have a seperate oil tank/cooler ?
Pete

 

[oldskoolmk1unoturbo]

yes there is an oil cooler, i guessed that the plugs would be oily when i looked at the oil dripping from the boost pipes,

could the oil in the combustion chamber be causing the miss fire?

 

[Chas Uno]

Is this the black turbo you're having problems with or Bushboys old red turbo you recently bought? Which one are you thinking of selling?

Can't offer any additional suggestions as to what is wrong because I have no experience with turbo engines

I do know that your black turbo is incredibly cool!

 

[oldskoolmk1unoturbo]

its the red E reg uno turbo which was previously owned by chris (bushboy).

I'm going to be replacing the turbo with a second hand one so it should solve the problem.

the black uno isnt and more than likely wont ever be forsale

 

[Louie Bee]

Hi All,

Sorry I’m late again...

Have you taken the Turbo’s air outlet hose off (the turbo) to check for play in the turbine wheel? Look for both up and down + in and out play, and resistance when spinning the wheel .

You can also check for oil sitting in the bottom of the air side.

One thing I’m not sure of it the type of breather system. If it’s the closed type, any oil vapour will be reticulated, and I guess will go back through on the low-pressure side (before Turbo). If so, it could well condense in the turbo’s air side, and make it look as if the turbo is shot.

An engine with worn rings will tend to breath more as pressure escapes from the cylinder(s) if I recall.

Another thought, have you removed a pipe from the air cooler? This is another potential collection point for oil.

My (MK1) Turbo, and air cooler both had oil in them when I took them off. I’m still not sure which way to go with it next .

Sorry If I’m confusing the issue. I’m new to working on Turbo engines too.

Oh, I can’t answer the original miss question. The gear selector rod isn’t hitting or disturbing anything when in 5th is it

Regards All,

 

[SteveNZ]

Keep in mind, oil in the intercooler and boost pipes is normal due to the recirculating crankcase breather. You need a hell of a lot of oil in the boost pipes before you get exhaust smoke.

It does sound like the turbo though, oily plugs are the only adnormality, are they really "oily" or just black?

 

[oldskoolmk1unoturbo]

they were very oily, not just black