tdiquattro

Thanks very much, I have been thinking about a set, but the price of the leather or part leather ones is quite a bit more, hmmmm. But I might just go for those as they look great, which runners did you use?

Thanks for the info and making the effort with the thread, really appreciate it!!

Cheers
Nigel.

John McM

Thanks, I checked that as a possibility and can see how that could bind the two pulleys together when they are meant to run at different speeds. I think I have that right.

My latest theory is that it's my new fan. I can push the fan on with just fingers, it's not an interference fit on the shaft.

The shaft and fan are driven directly but the bearing on the shaft may be rubbing rather than driven. I will find a suitable thread lock to test that theory.

John McM

No problem. I like sharing, particularly if it shares good info like the headlight fix.

The local seller selected the runners. Sorry I don't know what type/brand they are. They look standard though. Nothing special except the mod that gives me the extra height.

John McM

I reinstalled the fan, pulleys and shims etc, paying particular attention to anything that could rub. It seemed to work, then I got the dreaded 'ting ting ting' noise. I couldn't see any rubbing so there was only one option, pull it all back out....groan. The fan is closest to the shroud at the rear and that's where I saw some rubbing.

I had a number of options to fix this as I had a spare shroud, the old fan and new fan bearing. The spare shroud rubbed and the old fan bearing was too solidly in to change quickly. After a bit of research I decided to file the edges of the new aluminium fan blades and fit it to the powder coated shroud. I wouldn't do this if it was the original magnesium fan due to corrosion fears. In any case it worked

John McM

While I was sorting out the fan rub some new deliveries came: a heater bypass (supplied by Rose Passion) and new fan bearings (ordered from an Australian online seller) The latter were ridiculously inexpensive, but supposedly German quality. If an alternator refurb is basically replacing these, machining the slip rings and fitting new bushes I'm starting to see why it's relatively inexpensive, if you live in a country where a core replacement is viable (not in NZ). At some stage I'll refurb my alternator.

John McM

I fitted the heater bypass. Unfortunately it and the new fan shroud rubber don't want to play together. I need to work out a way to seal that as otherwise my cabin ventilation will suck in hot engine gases. I also need to research the mods required to get my '90 model front fans to work properly without having to set the temp to the cold or hot settings. Still it looks good, which is the point. I told my wife it was to compensate for the added kilos of new paint. She wasn't taken in, but it was worth a try.

John McM

With the fan sorted, it was time to fill the power steering pump reservoir and reverse out of the garage onto the car pad. I needed to be careful as once I do that I can only get back in the garage under its own power or with a flat bed tow truck (driveway is steep). It went out with no drama and I let it idle.

With both the oem cat bypass and after market primary bypass it's a bit on the noisy side, but I'll cope

John McM

I drove the car around the block in four short drives, checking for leaks in between runs. There was smoke pouring into the cabin as the various cleaning fluids gassed off but no leaks and by the fourth run it had settled down.

The only issue was stalling as I came up to intersections. I'll check my ECU mods to see if they are still there for the idle gain. Finally I parked the car and started to compile a list of the things to sort out. It's very satisfying to know it runs as the other items are small jobs.

John McM

In between fixing the fan and taking the drives I helped a fellow Rennlister take photos of his car. It's a '70 T with a 3.2 motor. The power/weight ratio it has will make it hard to keep up, but aside from the performance envy I'll admit to having unsavoury thoughts about that interior, especially the seats. It's all his design. Not sure where he gets his inspiration. It's the same guy that made the valve covers for my car. 911s were simple then.

John McM

You can ignore this. Just storing my ECU idle settings from an old post so I can refer to them later today when I check the ECU.

John McM

The ECU settings haven't changed, but I noticed that the throttle position was 99.45% on the parameters. When I checked the idle microswitch it was open. Closing it put the throttle position at 0%. So the problem with idle is the microswitch adjustment not the ECU. I also confirmed that WOT is not engaging. I will adjust the cables to give me WOT and then reset the idle microswitch.

As an interesting note I found out that the ECU has been logging engine operation so I know how long it's been operating and the rev ranges over that period, including the over revs. Just like a modern OE ECU.

porsche mania

John, your mates 70t looks great! Especially love the seats. I'd be worried about getting those carpets dirty rhough!

fishing

Wow, this is a great thread!!!! Thanks for sharing!

John McM

No problem. There are lots of views but few questions/feedback so good to know it is worth reading to some.

John McM

While I was looking through the ECU parameters I saw this page. It shows a switched setting at 5,700 rpm and an off at 5,500 rpm. That will be the resonance flap switch, which based on this graph (motec but still relevant) appears perfect