Wednesday, February 27, 2013

Carbon clogging and misfires in MINI engines

Earlier today we took apart an engine from a 2008 MINI Cooper S with 75,000 miles on the odometer.  The engine was clean and the services were all up to date.  The complaint:  A persistent check engine light.  The only stored codes were misfires.   The car had been to two other shops, and it had received injector cleaning, new plugs, new coils, a test for vacuum leaks (none found), and a test of the direct injection system (which it passed.)

None of those things had any effect on the engine light.  It might come back in 100 miles, or it might take 1,000 miles.  There was no pattern except this: it always returned.

This is what we found:

What you are looking at is carbon – baked on oil deposits – covering the intake port, intake valve, and valve guide.  The deposits are so think the cylinder didn’t work normally anymore. 

For purpose of comparison, here is a more typical intake port.  This photo is from a different engine – a Land Rover – but it’s got even more miles on it and as you see the valves are spotless

What caused that?  This MINI has a turbo motor so we quickly looked there.  Turbos are known to leak oil out their shaft seals.  But the turbo was clean

There was only one other possibility:  the crankcase ventilation system.  That system recirculates crankcase vapors, which can be laden with oil.  Indeed, when we looked at the hose, we found the same sort of clogging.

How do you prevent that?

Use a top-quality oil.  We use Mobil 1 and Amsoil almost exclusively.
Change the oil frequently
Keep the breather system clean

This engine is one of the new Bosch gasoline direct injection engines.  While that improves performance it can aggravate situations like this.  In a traditional engine the gas flowed into the cylinders through the intake ports, so it acted as a cleaning solvent to keep the ports clear.  Now, with GDI, the gas is fired right into the cylinder and nothing but air enters through the port.  If the air is laden with oil mist, this is going to be the result.

I expect this is not the last one of these we'll see

The final question in your mind is surely what you do about this?  There’s so much carbon that the only real cure is to pull the head and do a valve job/decarbonization.  However, this engine had a lot of wear in the lower end (separate issue) that caused the blow-by, so we realized the most cost effective cure would be an exchange motor from MINI

And that’s what we are doing.

MINI – can we repair one for you?

John E Robison
Robison Service
Springfield, MA

Tuesday, February 26, 2013

Repair or Restoration - which will it be?

You’ve got a nice vintage sports car, but it hasn’t run in many years.  Auction prices for these cars are rising.  Should you restore the car to show condition, or just fix it up to drive it?

Here at Robison Service we see situations like that all the time.  Sometimes the prudent course of action is clear, but other times it’s hard to decide what to do.

Sitting in the garage, it's a memory or a dream, but making it real may cost more than you think . . . 

In today’s market, the cars that bring those jaw-dropping prices on the televised auctions have been meticulously restored and detailed.  We do that level of work but owners must understand it comes at a price, as compared to basic mechanical repair.

Let’s look at the restoration or repair of a Jaguar XKE front end as an example.  This photo shows a typical old unrestored Jag; this particular car arrived here a month or so ago to join two other similar specimens in line for fixing up.

The problems in this front end are pretty well visible. The brake rotors are rusted. The rubber boots on the ball joints have rotted away, and the joints are loose.  The brake calipers are frozen from lack of use.  And the wheel bearings are sloppy.  The fix: a complete front end and brake overhaul.

If this was a modern Jaguar, we’d be able to do this repair in a day, using complete hubs and exchange brake calipers.  The parts would pop off and the new assemblies would slide on.  Old cars don’t usually go that smoothly.   We  can’t simply buy new brake calipers for an old XKE; the calipers the car has must be rebuilt.   Same for the hubs.  Everything is more time consuming because we repair, rather than replace.

In addition the scope of these jobs tends to expand when compared to service on a new car.  For example, we might need to replace the steel brake pipes if they don’t unscrew.  We might struggle with rusty parts that won’t come apart, and we will spend time cleaning things up.

The one-day job on a newer Jag may become a two or three day job on an older car.  Here's an example of how a simple task like "do the front brakes' expands from fitting front pads and rotors.  You pull the rotor and hub off the car, and the bearings are galled and the grease is chunky.  Add a few hours to rebuild the hubs.   When you remove the brake caliper for access, you see the rubber hose has cracks.  Add some time to take it off.  When you remove it, the steel line to the master cylinder snaps. Add half a day to run a new line.  When you go to bleed the system you feel a "bump" when pushing the brake pedal.  On closer examination, you find the master cylinder was corroded inside and the extra push of bleeding has pushed it over the edge.  Add a few hours to replace the master.  Do this at all four corners of the car, and you've added several thousand dollars of parts and labor to a seemingly simple job.  Every job on a vintage car has the potential for this kind of expansion.

So far, all we’re talking is mechanical repair.  What if the goal is restoration?

That adds a whole new level of complexity, because everything has to look new as well as function 100%.   That affects every single task.

First of all, when the area is stripped down for service, we now have to look at the underlying frame or body area.  Is it rusty?  Does it need paint?  Several days labor may be expended preparing the front frame to be serviced.  In many cases we spend more time on the cosmetic restoration of the areas being serviced than the repairs themselves take.

It’s no longer enough to simply replace parts.  Parts may not be available new, or else the current replacement part is a low quality reproduction you don't want to use.  It may be "new old stock;" a part that sat in a warehouse forgotten for fifty years, and it may not be good anymore.  Parts are a major hassle for vintage cars.  In the end, we often find ourselves making parts ourselves, or doing our own machining and rebuilding.  Once again that eats up time and money.

In this shot you see how a simple brake repair has expanded.  The brake caliper pistons are corroded and leaky.  The parking brake has worn out. The hubs need overhaul.   "Simple" jobs are rarely simple on a forty-year-old Rolls-Royce

When restoring, a simple functional repair is not enough.  We must also return the appearance of the parts to a new condition.  That may mean corrosion repair, cleaning, painting or plating.  We may choose to use techniques that were not available when these cars were made, in the interest of finish, performance, or durability.  A good example would be powder painting.  We may need to find alternative processes because the old ways are no longer done due to safety or environmental issues.  Examples of that are lacquer painting or cadmium plating.   All that adds labor time, wait time as paint and plating is processed, and of course there is the cost of it all.

The one day job on a modern Jaguar becomes a week, maybe two, maybe more of restoration work on the vintage car.   Always remember this:  restoration means bringing back the appearance and the function.   A true restored car drives like new - maybe better than new.  It doesn't just look good.  Painting over worn out parts is not restoration, though it's all too common as a means of cutting costs.

Service and repair is usually limited in scope. Restoration isn’t.  You can’t restore the front frame of a vintage car and ignore the back.  You need to keep going.  The result can be beautiful, and impressive.  But it is very time consuming, and time is money.

Repair work is guided by our knowledge of good practice, and we have many opportunities to save money.  Restoration is often guided by that car make’s Concours Judging Guide, and we have to follow the code strictly if we are to deliver good value in the end. 

It’s very common for a big British sports car restoration (Jaguar, Austin Healey, Jensen, Aston Martin) to eat up 1,000-2,000 hours of labor.  No matter how reasonable the labor rate is in your area, that makes for a big bill.

Wood steering wheels are beautiful, but they were seldom original.  Opinions about these custom touches vary from owner to owner, and car make to make.

Some cars will justify that work.   A rare Jaguar – a 120 roadster, a three-carb XKE – or an exotic Aston Martin may fetch $150-250,000 when restored.  For those cars, a very high level of work is justifiable. 

What about their little brothers – Triumph, MG, and  other cars that are so much more common?   They may be a little simpler to restore, and parts will cost less, but a top quality restoration will still eat up 1,000+ hours of labor.  If top quality examples of your make only fetch $25k it’s hard to justify restoration unless you do it yourself, as a labor of love.  Indeed, that’s what many of these projects are.

The XK120 above has been in the same family for sixty years now.  How do you put a price on that?  If you're in it forever, nothing but the best will do . . .

The final car I’ll consider is the top end – Rolls-Royce and their ilk.  These are much more complex cars, with higher standards of fit and finish, more expensive materials, and “more car” in general to work with.  Where a Jaguar can eat up 1,500 hours in a total restoration the Rolls-Royce convertible may consume 3,000, maybe more.

Values of finished cars vary wildly.  A 100-point restoration on a Silver Shadow may still fetch only $50,000.  A one-off Phantom drophead that was only a little more work to restore may be worth ten times that much in the end.  In that world you need to pick your projects carefully if value is your goal.

And then there’s the custom job – the times we are asked to take a car that was built as one thing, and make it into something else.  We make 88-inch Land Rover hardtops into 130 inch pickups.  We make stock Rovers into fire-breathing rock crawling monsters.  We put Rolls Royce leather and wood into American iron that newer saw anything but Detroit vinyl.

For those people – and indeed for most of our clients – cash value isn’t the goal.  Rather, the value for them is the joy they get owning a fine one-of-a-kind piece of automotive machinery, and using it for its intended purpose.  Most of these projects are Dad’s car; Grandpa’s car; the car we first dated in; or something else that gives that particular vehicle special significance and a value that goes beyond dollars and cents.  And those owners tend to be our happiest clients.

So what’s the takeaway from all this?  Think carefully about what you want.  Don’t confuse mechanical fixing up with concours restoration.  Don't confuse nicely painted but worn out junk with restoration.   If you want a custom job, think that through before you begin.   Remember that different people are happy with different jobs, and there are no right or wrong answers, provided the work you choose is done well.  That’s what we take pride in most of all.

If you’ve got a project you’d like to discuss, call me at 413-785-1665 or email Robison@robisonservicecom

John Elder Robison

J E Robison Service
347 Page Boulevard
Springfield, MA 01104

Thursday, February 14, 2013

Brake Failure - don't ignore the lines!

When’s the last time you inspected your brake lines?  Never, you say?  Maybe it’s time for a quick check . . .

The lines below were photographed on a 2004 Land Rover Discovery that was ten years old in the late winter of 2013.  The vehicle is in good shape, not rusted or damaged.  But it does live in New England, and that means the bare metal underneath is exposed to snow and salt.

We see a lot of "winter vehicles" this time of year at Robison Service.

Modern cars have pretty good corrosion protection for frames and bodies but we often see “other metal” left totally bare and unprotected.  That shows pretty clearly in the steel of the brake line ends.

Do you see the dampness - the darkening on the curved rubber hose - that's brake fluid seeping out.  And look at the deterioration of the top right fitting!

As you can see, the steel crimps at the ends of the rubber hose have rusted and swelled, and the connections have started to seep.  You wouldn’t feel that as a driver, and the level wouldn’t drop fast enough to put the BRAKE fluid warning light until a few months had passed.  This is a dangerous situation.

Why, you ask?

The connection between the rubber hose and the steel crimp has obviously begun to fail.  The steel crimp is clearly weakened.  What do you think might happen in a panic stop, with 2000 pounds of pressure in the brake line.

Bang!  Fluid sprayed everywhere and a line that blew off the clamp.  No brakes and a car rolling free, half a second from crashing.

And that’s the end of the brakes, the car, and maybe the driver too.  Sure, you could pump the pedal and get some brakes back, but with half a second in an emergency . . . that’s how many accidents happen.  At sixty miles an hour you're covering a hundred feet a second.  How much "think, react, pump" time does that give you, on a crowded road?  Mechanical failure has probably caused far more crashes than you’d think.  Many times the area that failed is subsequently crushed in the accident and it’s impossible to figure out what happened afterward.  The driver says “the brakes didn't work” but he gets surcharged anyway unless he can prove it.

And with brakes being brakes, he might not even be around to do that, if they failed at high speed!

For that reason, I urge you to check your car for incipient safety failures like this.  While you’re under there, take a look at the fuel lines.  Modern cars run 40-70 pounds of pressure, and gas spraying at high pressure near a hot exhaust is even more of a hazard than failing brakes.  It’s not too comfortable climbing out of a car when the floor is burning beneath you.

The picture below shows the cure for this car – a set of high performance braided stainless brake hoses from our friends at AtlanticBritish.  This hose kit is half a day to a day’s work to install depending on rust – there are a total of six flex hoses on a Discovery.  If your steel lines are rusty, the job can expand dramatically.  The flex lines are out at the wheels - easily accessible - whereas the steel lines are tied to the frame; carrying fluid from the master cylinder to the four corners of the vehicle.  The steel lines are much more inaccessible, as they were threaded through the frame early in the car's production process.  Replacement of steel lines can easily eat up several days of additional labor.  The photos in this story show a Land Rover but most other cars are similar.  Rolls Royce – with three times as many hoses – is notably more work but they don’t tend to be as rusty either.

On most cars a set of hoses won't set you back much more that $200.  It's pretty cheap considering the risk of letting them fail. 

This is what the new lines look line, installed, for comparison:

In this particular vehicle we had to change three steel lines.  The remaining lines were okay.  Seeing the deterioration makes me wonder how many other ten year old cars are out there, uninspected, on the edge of catastrophic failure.  

It’s something to think about, the next time your car is on a lift

John Robison

J E Robison Service
Springfield, MA 01104