The Lemon Fool

I never really wanted a turbo as I've always felt they were unnecessarily complex and potentially unreliable. I always believed that the way to more power was to get a bigger engine.

Anyway, now I've got a used petrol Focus with a turbo. Should I do anything differently? I've always tried to have 'mechanical sympathy' and would never rev an engine before it was warmed up. Presumably the same applies to a turbo, but as there's no rev-counter on the turbo it's harder to know what I can do to keep its revs low. And what about when stopping the engine? Does the turbo just sit there stationary, burning the oil in its bearings?

When turbos first came to prominence in relatively ordinary cars, Saabs in particular, the one thing I recall hearing was a need to idle for a time before switching off the engine, presumably to allow the turbo bearings to cool before the oil flow stopped.

I've only had one turbo, and it was a turbo diesel but there was nothing in the handbook about this, so I assume they are more user friendly these days.

That said, I think your approach plus perhaps a less aggressive approach just prior to reaching your destination might pay dividends.

I await others views with interest.

Turbochargers can crystallise the oil in their bearings, which then scores the bearings on start up, eventually killing the turbo. What I do with mine is drive the final few miles in low revs, and let the car tickover for about a minute before parking at the end of a long or fast run. You can't keep the revs down in a turbo - it will rotate at up to 100,000 RPM. They're supposed to get hot, very very hot, but as long as its allowed to cool down (which needs oil flow) then it'll last over 100k miles - mine has and that's in a decidedly sporty car.

As an aside - for turbo cars I'd totally ignore the manufacturers recommended oil service intervals - these are set to attract fleet buyers, not achieve optimum reliability. Mine has new oil every 6000 miles and again after winter, regardless of mileage. This is due to the oil crystallisation I mentioned.

If you service it yourself, then I'd recommend cranking the car a few times with the ignition fuse pulled, to circulate the oil before firing it up. Or just crank it so it doesn't quite fire up. Whatever you do, don't rev it immediately post oil service - give it a few seconds to move the oil.

I had a Focus hire car last year with one of those teeny eco-turbo engines. The engine itself was a cracker, but I do worry about long-term reliability on them. When I had a Saab, I used to drive gently for the last mile or so and not worry too much about sitting there with it idling for ages, I'll be honest.

I've recently started driving some marinised plant with a big ole' turbo diseasel engine, and the manual suggests a 3-5 minute turbo rundown period at idle after hard running especially, to allow it to cool a bit.

cheers,
TSC.

In the 80s I had a Renault 5 GTturbo. Two actually.
A 1986 that I kept until 1991, then another that I kept for eight years.
Both were new. Company cars.
Great, once one got used to the turbo lag. And the massive torque steer. And the piggish hot starting. And the lousy cold starting. And the bum-knackering clutch.

As to looking after it, I think Toponepercent has it right.

The only thing I would add, use the best fully synthetic oil, and if doing short journeys change it and the filter every 3,000 miles.

V8

I've had a Focus turbo diesel. It blew up! I'll never have another Ford as long as I live.

We don't actually know what went wrong other than all the oil disappeared into the silencer, the crankshaft started knocking and a replacement engine cost me in the region of £4K so I wasn't prepared to spend more money just to find out what had failed. There were other things that went wrong with this car. Suffice to say that I was glad to get rid after 58K miles.

Prior to that car I had a Peugeot turbo-diesel. Both vehicles were treated the same. The Peugeot never failed.

I now have a 1.8ltr Toyota petrol engine with no turbo. It's not the fastest away at the traffic lights, but so what, it does what we want. So far we have had 50K+ of ultra reliable motoring.

Regards,

ten0rman

Small turbos are fine and solid built.
Cooling down cycles only really apply if the thing was glowing hot from competing at Rev limits on a track day not general driving.

MyNameIsUrl wrote:I never really wanted a turbo as I've always felt they were unnecessarily complex and potentially unreliable. I always believed that the way to more power was to get a bigger engine.

Yep, me too. I always choose cubic capacity over anything that highly tunes an engine, be it turbos, twin cams, high compression ratios or whatever. I just don't think you can beat raw brute power.

The biggest block I had was a 4.2L Jag. But I've also had a 3.8L Mustang convertible and, back in the day, a Rover 3.5L V8. For my next I want an old 12 cylinder Merc.

Highly-tuned smaller-bore engines are also highly stressed, and so more to go wrong. A big lump is simpler and will soldier on even if it's misfiring. And only a big engine gives you torque, which means you can pull away at low speed in a relatively high gear. Far fewer gear changes.

Of course they guzzle petrol, but I do not do so many miles that that is a factor. I'll fall on my sword before buying a Prius. And Trump says climate change is a hoax

Lootman wrote:.....only a big engine gives you torque, which means you can pull away at low speed in a relatively high gear. Far fewer gear changes.....

I take it you haven't noticed the 1.6-litre Bi-Turbo (sequential/two-stage turbocharged diesel) that Vauxhall/Opel currently offer in various cars and vans?
300-350Nm between 1200-3600rpm.

BT63 wrote:

Lootman wrote:.....only a big engine gives you torque, which means you can pull away at low speed in a relatively high gear. Far fewer gear changes.....

I take it you haven't noticed the 1.6-litre Bi-Turbo (sequential/two-stage turbocharged diesel) that Vauxhall/Opel currently offer in various cars and vans?
300-350Nm between 1200-3600rpm.

Correct, I hadn't noticed that. But I'd expect a diesel to give me more torque anyway. Diesels need higher compression ratios, requiring bigger and heavier engine blocks. Better for torque but worse for acceleration. I've just never fancied a diesel.

I usually drive older cars and so have a preference for simpler motive power units and transmission chains. Less to go wrong.

google " tototrak v-charge "

long TRK.

That'll be "Torotrak v-charge", obviously. Nice company, has made a few bob for investors over the years.

BJ

Harrumph, terrible typo.
You have every right to be sarcastic bj. I have indeed lost a pocket on these and It has been an object lesson in why not fall in love with a share for me. But love is blind, and I still hold, and hope.

You have every right to be sarcastic bj. I have indeed lost a pocket on these and It has been an object lesson in why not fall in love with a share for me. But love is blind, and I still hold, and hope.

LOL, we've all done it. Torotrak was a stock market darling that went properly down the tubes, and not because its product was poor. I've got a fistful of solar panel manufacturers in my portfolio that have been blown out of the water by cheap Chinese competitors, so I know how you feel. Not even worth the bother of selling them, and I can't even paper the walls with the share certificates. Drat.

BJ