Project Rolla, Initial Inspections

I didn’t leave it long before I got stuck into playing with this thing. I needed to first check what sort of baseline for maintenance we had.

The engine bay was filthy, and the battery had been dead (I had to jump-start it when we got there to look at it), but that’s all I knew. Battery went on charge overnight and seems to be behaving its self, but will monitor it closely and replace it if need be.

You can see there had been some “coolant” explosion at some point. Lots of muddy brown, rusty water staining near the battery and coolant overflow tank. No doubt the whole system needs a damn good flush.

Thankfully the coolant is currently green, and although the thermostat is stuffed and takes ages to warm up and cools down again when driving, it doesn’t overheat when sitting, and the fan cycles as it should. The radiator looks quite new, but that could’ve been replaced when it had its front end bump (more on that later).

The first thing to check was the air filter. Dirty, but useable for now.

The rocker cover gasket has given up, there is oil everywhere. It’s also possible the distributor O-Ring has failed too, but it’s hard to tell with so much oil everywhere

I found the brake fluid was black, and was on the MIN mark when I got the car, to the point that the warning light kept coming on and off during the test drive. I topped this up for now, but will flush the whole system when I upgrade the brakes.

There is a bit of confusion with the spark plugs on these. It looks like the early cars used a different model and heat range spark plug, to the later cars, but the one consistent is that the gap should be 0.8mm.

These plugs were… Old. Maybe the wrong heat range too. I will be replacing these with BKR6E.

A 1.25mm gap, on the high side of the central electrode, which is worn away on an angle

The same story applies for the distributor cap and rotor. Both seriously worn out. There is a huge amount of buildup on the cap terminals.

The oil, although jet black, was 3/4 full, which considering the oil leaks, is good. This will get changed anyway, just so I know what’s what.

This is where it started to get a bit weird. After checking everything, and reassembling, the car was hard to start and idled very low and rough. I started to do my usual checks of the throttlebody and found a few things. First, the throttle stop has been wound right out so wasn’t touching the throttle pivot, leading to the throttle over closing and jamming, causing a sticky throttle.

Secondly, I found the TPS was loose and a goose. There is a gap between it and the throttlebody

Removing the TPS showed that the metal tab that should stop the TPS winding back too far had been bent and no longer served its purpose. It should stop at that diagonal line at about 4 o’clock.

I bent the tab back and reset it

Using feeler gauges and a multimeter I reset the throttle stop and TPS adjustments. Long story short, use 0.7mm of feeler gauge between the throttle stop, and adjust the TPS so that on the two lower pins you are just on the edge of going from having resistance to being open circuit. This should more or less set the idle switch.

It turned out to still idle rubbish after that, so I pulled the throttlebody off, removed the idle valve and cleaned the whole lot. The idle valve was stuck, so freeing that up should be good.

It idled better after all that, but the idle speed was still all over the place. Sometimes low, sometimes really high. A split vacuum hose to the FPR was found and replaced, with no change. I did find that the base ignition advance was set to 15deg, when it should be 10deg. Changing this back slowed the idle enough to bring it into a reasonable speed. Replacing the thermostat should help too, so parts are on the way.

In the mean time the idle is a little random, but when I took the car out earlier it behaved perfectly. A little high when cold (started OK but crept up), but as the temperature went up the idle went down as it should until it settled at about 600rpm in gear. That’s how it should be.

I do wonder if someone had been messing with the throttlebody to try and fix the idle issue, and just didn’t do a good job of it. No surprise there.

Service parts will be here in a couple of days, so I’ll spill some more oil and coolant on the ground, and see how we go after that.