Last weekend my wife Maripat and I had the privilege of visiting the Pittsburgh Vintage Gran Prix as a guest of the Allegheny Region of the RROC. It was the first time I’d done a car-related workshop in that part of the country and I was honored by their invitation. Thanks to RROC member Dan Heit who set things up and everyone who worked to make the events of the weekend a success.
We began with a reception at the home of Sandi and Bernie Pinsker. There were at least a dozen Rolls Royce and Bentley motorcars - and a somewhat larger number of owners – in attendance. I was surprised and pleased to see several familiar faces and cars, 400-some miles from our home.
I was also happy to see Dr. Nancy Minshew from the University of Pittsburgh Autism Center of Excellence. However, I should not have been surprised because the Gran Prix is run as a fundraiser for the Allegheny Valley School and the Pittsburgh chapter of the Autism Society of America.
Being an autistic person myself, I never know what to say in those situations. I also have trouble with “noise clutter” at gatherings like that. Consequently, my wife and I retreated to the front porch, where we admired the cars and talked to anyone who ventured outside.
As darkness fell we trooped over to the Green Oaks Country Club in nearby Verona for dinner and conversation. I spoke of my experience growing up, learning about Rolls Royce motorcars, and answered questions from the audience. It was an interesting night for sure. Autism disabled me as a child, but it gave me a powerful ability to focus, and an unusual insight into machines. I believe that is one of the main reasons I have been successful caring for these cars. I don’t think I’d be an RROC tech consultant without that! Anyway, I hope the club members in attendance enjoyed my stories.
The following day we joined 400 other vehicles for British Car Day in Schenley Park as the vintage racers ran qualifying laps around our field. I held an impromptu tech session as we looked over member cars and discussed possible service issues.
I saw a few problems that were common to many of the cars, and I’ll share them here just in case you recognize one or two on your own PMC . . .
Several folks with early fuel injected cars complained of rough idling. I offered a few suggestions for that. First – make sure the plugs, wires, cap and rotor are good. If the engine is still rough, take a wrench and crack the fuel lines at the fuel distributor one at a time. When you loosen a line you should hear the engine stagger and you should see fuel wetness around the fitting. Are there any cylinders that don’t respond the same? If so, swap those injectors and try again. If there’s no change you probably have low speed clogging in the fuel distributor.
Another cause of rough idle is vacuum leakage. I suggested using a smoke machine (any emission shop should have one) to look for leaks.
Finally, I advised looking at the distributor. Remove the cap and twist the rotor. Does it turn a few degrees and snap back to position? If not, there may be a problem in the advance. Shake the center shaft. Is it loose? That will give a rough idle, for sure.
Then I had the question on the BRAKE PRESSURE lamps. How do you know when they are bad? Start the car, run it 5 minutes, and shut it off. Turn the key on, but don’t start the car. Pump the brakes. How many pumps do you get before the lights come on? In my opinion, any number under 20 is marginal. If you have less brake energy storage than that, and you stall the motor on a hill, you are in big trouble. You are going to crash. Three of the cars in the show held ten pumps or less – too little for safety in my opinion. Change your accumulators – they are cheap, especially when compared to accident repair.
Next we looked at hard ride and bouncy cars. The most common cause of this is worn out gas springs in the rear suspension. These “springs” are really balls filled with nitrogen gas behind a Mylar diaphragm. They are very similar to the brake accumulators, checked in the previous paragraphs.
When you hit a bump, oil flows out of the shock, down a line, and into the gas springs where it compresses the nitrogen gas. Hence the name “gas spring” When the springs age nitrogen diffuses through the barrier and into the hydraulic oil where it is lost. Once the nitrogen is gone there is nothing to compress, and the car rides like it has square wheels.
These nitrogen filled spheres lose their charge as they sit. Driving or storing the car makes little difference. Expect a 4-6 year service life in most cases. If yours are getting to that age, I suggest taking action now. Driving on weak brake accumulators is dangerous, and driving on weak gas springs can blow your rear shocks – and that can be a $3,000 problem on some of our cars.
The next thing I will mention is cracked hoses. I saw many examples of fuel and coolant hoses that had visible dry rot cracking. Change those hoses right away! That cracking is the one clue you will get that they need to be changed. Blow a hose and spray fuel or coolant onto a hot exhaust manifold, and you will lost the car to fire.
And that takes me to my last point. Fewer than half the cars I looked at had fire extinguishers on board. You know something? A fire extinguisher is like a shotgun. You don’t need it very often, but when you do, there is no substitute. I strongly suggest every collector car be fitted with a good side unit in the trunk where you can get to it fast. The best models for collector cars are the CO2 units in the 15lb size range. Those will knock down engine fires with little to no damage.
The race itself was great, but it's going to have to be the subject of my next posting. Meanwhile, look on my Facebook page for shots of the vintage road action, and stay tuned for my next story.
Best wishes
John Elder Robison
John is the General Manager of J E Robison Service Company of Springfield, Massachusetts. Robison Service is an independent RR/B service shop that specializes in restoration and major repair of postwar motorcars. Find them online at www.robisonservice.com
