Automobili per idioti – or how to restore a classic Maserati

Vroom!

Bought a battery charger last night, pulled the battery and measured 10.09vDC. Dead as a doornail.

Hooked it up and left it all night, measured 13.35vDC this morning. Much better.

Popped it back into the car, reconnected the wiring, measured the voltage once more, still good, about 12.50vDC.

 

Put the key in the ignition, turned to “on” position to get the fuel pumps running, gave three pumps on the accelerator to prime the carburetors and twisted the key to “start”.

 

No Mopar whine, no clicking, whirring or anything. The engine simply roared instantly to life.

We’re back in business.

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Starter motor

The car arrived when I bought it with an extra starter motor. Foresight?

I had both rebuilt shortly after rebuilding the transmission with original OEM parts. The shop didn’t comment on them when they did the job (in fact initially they couldn’t do the job at all because they didn’t know where to source the parts), and when I picked up the car she fired right up with the characteristic Mopar whine.

Only a day later, while picking up someone at the airport, the starter failed again and left us stranded. So we got a tow back to the shop who swapped starter motors, the original one going into the trunk for later analysis. The shop proceeded to blame the problem on crappy parts, the parts place claims they are US OEM and the best quality available.

That ‘later analysis’ took some time to perform, as since the car started (mostly) fine, there were other things to attend to, so it was put on the back burner until later.

After installing a new cable and still not starting (yes, I did use a booster since the battery was slowly being drained), I figured I could install the starter motor that had only been in the car for a day. Since both are identical and both were rebuilt at the same time with the same parts, it seemed reasonable to assume that it would work better than the one in the car, even if it still gave the occasional hiccup.

I like to try to learn from my mistakes (but by no means manage as often as I’d like), and figured that before jacking up and crawling under the car it would be a good idea to bench test the starter. So we clamped it in a vice and provided it with 12+ volts, shorted the terminals and got “click, click”.

Hmm. Spot a trend here?

Imagine my delight at having figured that out *before* installing it in the car!

It seems about time for that “later analysis”, so the starter went back to the shop for dissection. Two days later the verdict was ready – the solenoid was burned out. After only 1 day of use from new. I guess some things just aren’t made like the used to be.

Examining the options, it seems the Nippon Denso reduction starters are drop-in replacements for the original ones, weigh half as much, offer higher cranking power and require less juice. Sounds like a win-win situation all around.

Looked over the models available and narrowed my choices down to three units.

Tuff Stuff

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MSD DynaForce (it’s RED!, although on closer inspection looks an awful lot like the Tuff Stuff starter above, and it’s impossible to see once installed anyway)

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RobbMC Performance

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As I wanted to stick to a budget for this restoration, I went with the most affordable option first, thinking I could always get one of the fancy ones later if it doesn’t work. Although I really have to admire RobbMC’s customer service and information along the way, even though I decided not to get their starter. I might get one anyway, they were really so helpful, and their starter seems really to be a cut above the others and offers flexibility in configuration that no one else does.

What a difference between old and new!

New starter on bottom

New starter on bottom

Still wanting to live a little dangerously, I installed it without bench testing it first. All of these after market starters have tried to improve on the original design and make things easier to access by mounting the terminals on the top when mounted in the ‘normal’ Mopar position. Since mine goes on the other side of the engine, the terminals are on the bottom, facing the pavement. Not a big deal, but not what I’d prefer.

It’s amazing how tiny and light it is in comparison with the original.

Anyway, I bolted it up, connected all the wiring and plunked myself down behind the wheel.

Turned key…..

“Clackety clickity k-k-k-k-k-k”
Sounds a lot like a ratcheting noise.

Tried again and the engine turned over!

But very slowly. Too slowly to be of any use.

Doh. Battery is dead. Too many tries previously, even the booster can’t provide enough juice to help.

So I’m off to buy a battery charger.

Stay tuned.

arrived from Italy recently, thanks Campana!

Starter motor cable

Starter motor cable

Having sleuthed our way to the cable as the culprit for the starting problems, I was really looking forward to getting this installed into the car.

The old one was completely drenched in 34 years of oil, grease and road grime, and showed signs of corrosion.

A little bit of adjusting at the starter motor end and we’re ready to go (unfortunately some of the grime from the old cable managed to escape and attach itself to the new one):

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Maserati decided in classic Italian tradition to mount the starter motor on the passenger’s (right) side of the engine, whereas the ‘standard’ Chrysler/Mopar placement is on the driver’s (left) side. Since the cable connectors are on the outer side of the starter motor, this arrangement works pretty well, although it is a tight fit to get the locking washers and nuts on and tightened down. Removing the tire helps.

I probably don’t want to know, but suspect that the brake line heat shield is lined with asbestos. Sure looks and acts like it. Yuck. Of course I managed to dislodge half of it while removing and refitting the cables.

New cable installed

New cable installed

Drumroll…….

 

 

 

Turn key……

 

 

 

 

 

 

 

 

 

 

 

 

Click click :-(

Well, sh*t.

 

Start problems

Sylvia has been giving me intermittent starting problems the last few years. Rarely has it been so bad that she wouldn’t start at all, but it’s gotten progressively worse.

While on my way to catch a ferry after visiting friends in Amsterdam I stopped in Germany to get gas. I wasn’t on a very tight schedule, but did want to arrive at the terminal in time to relax a little and enjoy the trip. After filling up, the car refused to start. The dreaded (but by now familiar) “click-click” happened each and every time. Usually after a few attempts the engine fires up, but here in the middle of nowhere, Germany, a half an hour later I was starting to sweat a little.

A nice old man was kind enough to give me a jump (but the problem isn’t a low battery), Sylvia finally took the hint and roared to life. I didn’t turn the engine off again until I was on the ferry!

So it was time to get to the bottom of this. A fellow owner had made his own investigation and caught the pinion gear red-handed stopping before it engaged the ring gear. At the time both of us thought that the “click” sound was due to the gears hitting each other, but not continuing past that point to engage. Later we discovered that they never got that far.

I started by measuring the voltage in the battery and checking the starter relay. 13.8v in the battery, the relay was worn (apparently arcing) but worked fine and passed current.

Next up was to check all grounding points. Each one showed good and constant ground, meaning that the problem lies elsewhere.

I would have suspected the starter motor, but it’s been rebuilt. In fact both of them have (always good to have a spare), with US sourced OEM parts (see one of my previous posts about the same, found here).

The detective work continued by measuring the voltage at the starter when cranked. The wire from the battery to the starter is huge, probably 1 guage or so. The one to the solenoid is smaller, and is spliced to a wire that leads into the cabin and the relay. We found that the splice was stealing over 1/2 a volt, and by the time it got to the starter solenoid there were only 9.7 – 9.8vDC, while there should be at the very minimum 10.5 – 11vDC to engage the solenoid and trigger the starter.

Judging from the looks of the cable, together with its age, it’s past due for replacement. A new one is on order from Campana in Italy. If the problem persists, at least one variable has been eliminated.

Will it start..?

Running rough

After the carburetor rebuild, I had expected the engine to purr like a kitten and scream like a race car. This is a Maserati, after all.

Such was not to be the case.

Dialing in the correct air:fuel mixture with a Gunson Colortune seems straightforward enough, as well as mighty clever. You can actually see what’s going on in the combustion chamber while the motor runs. Pure genius. I first disconnected the air pump and vacuum system as per the service manual, but found it nearly impossible to find a good (and stable) idle speed as well as the proper light-blue flame in the cylinders.

One issue was that I was only seeing combustion every 1 or 2 seconds on average, the rest of the time all I could see was a spark. With the colortune it’s WYSIWYG, so something was wrong.

The other issue, which later revealed itself to be dependent on the first, was that several cylinders were impossible to get a nice bright blue flame by tweaking the idle mixture screws. I did as best I could and the car ran ok, just not as smoothly as I wanted.

At higher rpms I was able to observe continuous combustion and with an appropriate color. So it seemed that the acceleration circuit was working correctly.

Still, the car would at times idle a bit roughly and still felt a bit less powerful than expected, and the number one cause of carb problems and uneven running is air leaks. The timing had already been checked and set by a mechanic during one of the previous dyno runs.

My car is a US spec one, meaning it’s fitted with emissions equipment in a (futile) attempt to reduce its substantial contribution to global warming. I’d like to say I do my part, after all I did fit catalytic converters on the car.

A friend came by and we mapped out the vacuum system, tracing each hose and line in an effort to pinpoint any potential problem or leak.

There’s a diagram on the inner fender, passenger side, but basically there’s a  cam cover breather hose and recirculated fuel/air pipe off of cylinders 1 & 2, and there are hoses forming a loop off the front and rear of the intake manifold. These are controlled by 2 solenoids , the one closest to the firewall activates the vacuum advance on the distributor, the other appears to be connected to the charcoal canisters. There are butterfly plates to close the air input in trumpets of air box when cold, until the engine warms up, and charcoal vapor canisters to collect unburned vapors off the carbs and cam covers.

Following the vacuum lines with the engine running, we quickly discovered that the solenoid that controls vacuum advance wasn’t doing its job. It wasn’t clear if it had reached retirement age or was on strike, but by bypassing it (easy enough as there already was a tee there to connect from the solenoid to the hvac controls in the car) the idle smoothed out instantly. That one small adjustment, and suddenly Silvia sounded a lot more like a Maserati!

Smog system solenoids

Smog system solenoids

Without the help of the vacuum advance, the mixture in the cylinders is ignited too late in the Otto cycle to make power, allowing for the speed of the engine. That explains why at higher rpms the engine was running better, as the mechanical advance takes over for the vacuum advance used at idle. When we bypassed the solenoid, effectively putting the vacuum advance “on” at all times, the idle smoothed out and we were able to tune the carburetors for ideal air/fuel mixture.

Our assumption received further confirmation when we hooked up the Colortune again and were easily able to dial in picture perfect blue-flame combustion on all cylinders. Some were easier than others, it might be that the adjustment screws need replacing.

With this taken care of, next up is to register consumption and power over the next few weeks and then revisit the timing to get it as optimal as possible.

Carburetor rebuild

After a day at the dyno shop, their recommendations were to fix the leaking exhaust and clean and rebuild the carbs. No. 2 carb was leaking, and they adjusted the others as best they could. The car felt peppier and had more power, but there’s always room for improvement.

I pulled the carbs off of the manifold, the job is pretty straightforward. Remove the air box and lay it off to the side, unbolt the trumpets from the air box baseplate, disconnect the vacuum & breather hoses at the same time.

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Remove the choke wire on the drivers side and disconnect the microswitch connector. Pull and plug the fuel line from the fuel rail input. Loosen the hose clamps on each fuel inlet line and remove the fuel rail. At this point you can loosen the nuts holding the carb baseplates down and remove the carbs. Note that carb 1 and 2 (counting forwards from the firewall) hold each other in place, meaning you may have to remove carb 1 before 2. I started with carb 4 and worked my way backwards when I discovered this the hard way.

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Inspect the phenolic riser plates for wear and unevenness, anything that can let ‘unmetered*’ air through is a bad thing and will cause endless headaches, bad running and a general all around bad mood.

Plug the manifold openings to prevent unwanted objects from finding their way into the cylinders. That would really ruin your day.

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Coming up: carb teardown.

*unmetered – a carburetor is essentially a controlled air leak into the engine. It mixes a precise amount of fuel with the air that flows through the venturii to provide an optimal fuel:air mixture. Any air entering the system by other means, ie via a leak, will unbalance the ratio and render all tuning and tweaking moot.

Racing dampers

or “shocks and springs” for US readers. I.e. the whole enchilada as far as wheel control goes (aside from torsion/anti sway bars).

While the car was being prepped, I had the new dampers re-valved. Öhlins dampers have the feature of being able to be tweaked and tuned to any specific response curve desired. By changing the metal washers that regulate oil flow they can make them super stiff for racing, or very relaxed and soft for cruising. On top of this, there is a click adjuster on each damper that allows it to be tuned within a wide range determined by the internal valving.

custom configurable valving

custom configurable valving

Mine had been set up a bit too harsh, and the click adjuster didn’t allow enough adjustment to soften up the ride, so it was back to the bench to re-valve the units.

The guru himself gave a quick introduction to how these dampers work and what makes them so much better than anything else out there, as well as why a range of sports cars are delivered with Öhlins as standard.

Damper Dave explains the theory and operation behind Öhlins dampers

Damper Dave explains the theory and operation behind Öhlins dampers

After the new valves are configured for the desired response, the dampers are filled with a special oil and then put on a dyno to test. Mine turned out a response curve that perfectly matches the OEM dampers, yet can be tuned via the click adjuster to offer a much firmer or softer ride, whichever is preferred. All of this while the damper is on the car, simply by reaching a hand under and turning the adjuster wheel one way or the other.

filling the damper with oil, taking care no bubbles remain

filling the damper with oil, taking care no bubbles remain

on the dyno for testing

on the dyno for testing

Back on the car, and the ride was completely transformed. Previously the front and rear end felt almost like two different cars due to the difference in response, now the car felt like one solid whole and the front matches the rear perfectly.

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Last thing to do is to dial in the ride height, done by adjusting the spring preload. If you look at the picture above you can see the spring seat is actually a threaded ring that can be adjusted along the length of the damper tube, and is used to fine tune ride height and spring preload. My car is riding a bit too low at the default setting.

 

If you have a QP3 and are interested in a set of dampers like these, let me know and I’ll see what I can arrange :-).

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