Quattroporte III catch-all thread

Have had a few nice drives since I came home with the car the other day, still waiting for the last parts to be fabbed before we finish the suspension.

Brought her down today to go for a drive in the mountains, left her idling while I went inside to get my guests. Came out, sat in the car, started to drive off and the steering wheel wouldn't move. I also noticed that the alternator charge was way low, like 8v.

Hmm...

Popped the hood and had a look. Coolant is dripping slowly from the upper hose onto the belts and pulleys, and my main belt (the one I paid a mechanic to replace) is worn, chipped and missing bits. Giving some throttle shows the belt smoking, indicating slippage.

To get to the main belt (alternator and water pump) you have to remove the power steering belt. Does't seem too big of a problem, but it took me a few hours because I don't have a jack or lift and I didn't have the right tools. The tensioner wheel was at minimum tension, at the top of the slot. The front bolt is 27mm, the rear nut holding it in place is 22mm. It's a bit of a pain to get to, and to get the belt off of. I removed the circlip and was hoping to remove the bearing to repack it (it sounded fine, but since I had it off the car it made sense to do it), but wasn't able to get the bearing out, so left it.

The alternator is on a bracket that allows it to pivot/swing, the bottom of it is connected to the top of the power steering pump, as far as I could tell.

Got the belts off, put the new main one on, and again a pain getting the tensioner wheel in place. I ended up putting the belt on the PS pump and crankshaft pulley first, mounted the wheel on the bracket without the belt on, and then used a screwdriver to stretch the belt over the tensioner wheel after everything else was in place. The main one went on with no problems because you can swing the alternator aside to fit it.

I'm not sure how tight the belts should be. The PS one is pretty much the same as before, it's the same belt and the tensioner is at the minimum setting as before. The steering feels pretty much the same is it did before. The main belt (alternator/water pump) whined when I had it at what I thought was an "appropriate" tension, and the voltmeter showed 12-13v charging after a second or two. If I slackened it, I only got 8-10v on the voltmeter, but it didn't whine. I ended up with a setting in between, and found that if the alternator bolt isn't super tight, it won't whine as readily as when I lock it down very firmly, and still charges ok, at around 13v.

Started up and charging is still a little erratic, sometimes it shows only 10-11v, other times it will creep up to 13v after a while. The belt whines rarely, usually when accelerating and the car has just been started, not after. Any tips as to proper settings (I don't have the alignment tools or a tensiometer) are welcomed.

The mechanic said that the coolant leak was probably because the car hadn't had a properly pressurized coolant system for years, and any loose connections would be extra stressed with the new radiator cap. I did note that the hose wasn't super tight, and also that it had been pushed off the metal manifold part by about 1/2". After opening the cap I pushed the hose back and went over and tightened all hose clamps - the one that had moved was a bit loose.

Hopefully this will solve the issues that cropped up today.

We managed to go for a drive after all when I was done, I'm not 100% sure but it looks like I actually get worse milage now than before, down to 30l/100km from 20l/100km. Which is strange as the car is running better than ever, aside from the lower vacuum (consumption gauge) than what I had previously.

Anyway, just rambling. Fix one thing and two more things break. That's how it goes when you have an old car...

 

Hi Tony,

you're right, the manual does specify that, lacking a tensiometer, the belts should "be stretched with more force than the belts commonly used on other cars."

I can provide another nugget of info, provided by the tow truck driver who picked me up today when the belt broke.

If you hear the belt whining, it's too loose. That's a sign that it's slipping. It's hard to over tighten a belt, and if you do you'll hear the bearing on the water pump/alternator making an uneven sound, but not whining.

So when I loosened the alternator a touch to eliminate the whining, I did the wrong thing and made it more likely to fail, which it did, extremely quickly.

Once more - whining - tighten the belt a little more. No whining - all ok. A straining or uneven sound is probably an indication of too tight belts.

So back to the workshop the car went, I'll have them take care of the belt when they finish up the rear suspension.

Live and learn. I certainly learned a lesson today. Glad it didn't happen yesterday night when we drove a few hours up into the mountains...

 

I suppose you could, but I think they're supposed to be CAD plated. Mine are.

Same goes for the vacuum actuators on the airbox trumpets.



Sent from my iPhone using Tapatalk

 

"In the US it was called the Royale, built to special order with only 5 sold."

Ummmm, no.

Nice to see the QP3 being appreciated, hope that helps the value appreciate as well.

 

Anyone want to join in and think out loud with me on this one?

After adjusting the timing to factory spec (IIRC it's now 6 degrees BTDC static, vacuum retard has been disconnected), setting all carbs to flow exactly the same amount of air (5kg/h) and using a Colortune to get a nice bunson blue burn in all cylinders, an admittedly non-scientific test leaves me with even worse milage (50% worse) than before!

The "low fuel" light had just come on when I picked up the car last week. I filled 25l of fuel and went for a drive with some friends, up in the mountains and back. 75km round trip. When we got back to town, the "low fuel" light just started glowing again.

So assuming we used around 25l for 75km, that results in 30l/100km (8mpg)! This was on back country roads, and I was consciously careful using the accelerator, keeping things as gentle as possible.

Before the timing adjustment and carb tuning (but after rebuilding the carbs, leaving the timing as it was) I was getting between 18-20l/100km (12-13mpg).
The best I've seen was 16l/100km (15mpg), and Jarle (CharlieA) claims 12-13l/100km (18-20mpg), although I haven't seen him post here in a long time. He did mention that the engine likes a lot of timing advance, but he didn't say how much.

The engine runs really smoothly and revs great, pulls well and seems good on power, even better than before. I do plan to test the milage again more rigorously with a full tank of gas and a few longer trips.

But aside from timing and carb tuning (idle mixture adjustment), what else should I be looking at, and what else would adversely affect mileage? I do notice that the consumption gauge shows less vacuum, and less stable, than it used to (needle wavers/bounces a bit, and jumps straight to red on acceleration), although I'm not sure if I should pay attention to it as indicating anything relevant at all.

Ideas? I hope to either find someone with a dyno or an exhaust gas analyzer (or both) and see if any additional clues show up.

 

Thanks! Good idea.

The shop did check it and found I think 26 degrees or so BTDC (from memory) at 3500 rpms or so? I may be wrong, but that's certainly something we can look into. I think the manual specifies max 37 deg BTDC at 5000RPMs.

 

For stuff like this I usually jack it from the middle of the front crossmember, right in front of the oil pan. Put a piece of wood or something pliant between the metal surfaces. Then I put jack stands under the jacking points behind each of the front wheels and slowly ease it down onto them.

I don't recall any cover on the starter. You'll of course want to disconnect the battery, and removing the wheel makes it much easier to get to the bolts. Other than that it's pretty straightforward. Two bolts keep it in place and there are two nuts keeping the starter cables in place.

Hope this helps!

p.s. If you bench test your old starter, let us know what's wrong with it. Mine kept going through solenoids, and I finally replaced it with a Denso reduction starter. So far so good.

 

I got to mine through the wheel well, although I found it easier to mount the new starter's top bolt from under the front of the car, with a long extension on my ratchet.

It's pretty straightforward, really, you'll see when you get the car up on stands.