bstark

Hi Jonathan, I've seen that link before and it's useful, although some of the tests aren't very practical given the location of the regulator (which I replaced with no change to the symptoms). Fan belt is tight. Other than engine load there is no difference in conditions. The cooling system is the standard fan arrangement.

This is slowly doing my head in ... The car is a sixties Fiat 500 running a dynamo, separate regulator, points and wasted spark ignition. All was well until a few weeks back the ignition light came on at speed on the motorway. Car drove fine but at anything above about 2500rpm the ignition light came on. Have since had the dynamo checked out and apparently brushes, springs and bearings are all good. Have fitted new regulator. Tested in garage and light goes out once started and stays out even when revved hard - hooray! Go for a drive and almost immediately the light comes on when revved - pretty much only goes out at idle or at less than 55km/h in top (guessing about 2400rpm), so presumably load related? Electrics are not my thing and short of spending time and a chunk of cash replacing the apparently sound dynamo with a new one to see if it works I'm at a loss. Is this something that could be caused outside of the dynamo and regulator, eg. The wiring between or the battery or something? Help appreciated! Bob

After a (preferably heated) windscreen to suit a '92 Supersprint. Mine is now sporting a large unrepairable chip that looks like a bullet hit it 🙆🏻 Bob

I'm curious as to how well they perform on a dry track? I'm by no means a pro, and I'm still learning grip limits in the car (I got passed by an academy car on my last trackday and his tyres were clearly less grippy than mine!). Do you think the 21's could be a good option? AO21R's are fine on track but can overheat if its a very hot day. The tread doesn't wrap round the sidewall in the way, say, an R888 does so excessive roll can lead to you falling off the tread onto the plain sidewall a bit leading to loss of grip on the limit in the way you don't get with an R888. It isn't drastic but it is limiting (or fun, depending on how you look at it). Having said that I've done several track days on 21's with no issues, and they are very much your friend should you get a bit of rain on the day. Bob

Due to an impending new car arrival my trusty Mazda 3 Sport is for sale. This is the most reliable car I have ever owned and is in great condition inside and out. Everything works, it has a full service history and is taxed and MOT'd to March 2014. Equipment includes automatic climate control, electric windows all round and an excellent Bose sound system. Goodyears with decent tread on every corner. Really comfy sports seats (chosen to alleviate my bad back). The car drives beautifully and has been well looked after. I get 33-36mpg depending on the journey. I originally bought it as a stop gap having had company cars for many years and have kept it for three and a half years having been so impressed with it. Full advert and pics on Pistonheads here

If you're still running a dizzy then a switch to Megajolt 3D ignition should be in your budget, and then get that set up on a rolling road. Transforms the torque and driveability of the xflow, and makes the car noticeably quicker in most circumstances and against the clock on track. Max power probably won't increase but you will get more of it more of the time, if that makes sense. . Bob

Well so much for my confident assertion it isn't wheel balance I've never had a wheel balance vibration before that you couldn't drive through with more speed. Swapped fronts and backs and whilst still slightly there it's a massive improvement and all but gone. As I said it's always done it to a degree, and with different wheels and tyres. It had just got so bad recently I finally resolved to do something about it. I'm kind of confused now but will bung a new set of AO21s on (these are getting on a bit now), watch the guy balancing it like a hawk, and then take it from there. Cheers for humouring me everyone. Bob

Thanks for all the suggestions. Gave the car a good going over last night and have ruled out hub/bearing, track rod ends, steering rack and mountings, stub axles. Swapped the wheels around so will see if that helps when I take it back on the motorway later. Hopefully it's a simple as the tyres going out of shape whilst standing over winter and a new set of boots will cure it. Bob

7 Wonders - no idea but they've been in business for years and I haven't had a problem on the rest of the fleet (same fitters). Pendennis - pretty certain mine is set for zero toe out

If it hadn't been doing it to a degree before the refurb I'd be getting more worried for my wallet

Thanks Jez, will try that. Caterbram, yep it's a live axle that's had a lot of money spent on it and was completely rebuilt a couple of seasons ago with new bearings, a new half shaft when a stress crack was found, and is now baffled to within an inch of its life, as well as a check on the CW&P and the ATB Tyre pressures would of course be easy to sort - it did sit for a long time this winter but as I said this has been an issue I've just lived with for years (for some reason ) Bob

Grim reaper - this isn't what occurs with mine at all. Poor road surfaces are fine and there is no bump steer. This is purely at speed and can occur on newly laid surfaces that otherwise feel smooth-as. Jez, Charles, is there an easy check I can do for the bearings without specialist tools? The discs are a thought as well. Swapping the wheels around us of course easy so will try that. I take it the general consensus is that it is unlikely to be the cycle wings, then?

Interesting... Almost certainly were balanced on the centre holes... Bearings , pivots, track rod ends etc. went through the mot fine recently and the car feels a as planted and direct as you would hope so I haven't specifically checked them, no.

I'm not sure why I've put up with it for so long, maybe it has gradually got worse over the years, but at motorway speeds I get a serious 'out of balance' style steering wheel shake. The wheels have been checked and are balanced. The thing is, you can't drive through it so it doesn't lessen or disappear with more speed. It does, however, come and go, and it tends to be either there or not (not a sliding scale of severity). Pretty certain it isn't road surface related and am getting the feeling it is more to do with what the wind is doing. Hence I've been wondering if it's aerodynamic and down to the cycle wings? Does this sound likely? And if so is it a case of TADTS or is my car just 'special'? I've owned the car for 12 years or so but didn't build it. There is star crazing around the wing mountings on the left hand wing (car over 20 years old now) whilst the front mountings on the right hand wing could be tighter (they don't exactly rattle though, and are also seized). Anyone experienced and cured this? Bob

Mine has various mods to encourage the oil to stay in the engine at high revs on track (at its worst on uphill left handers where it used to try and come out via the dipstick tube), and at least go into the catch tank if it does. Prior to this it would try and blow the filler cap off... Been like this for years and touch wood still pulls like a train and sounds lovely. Put out 138bhp at 6,000rpm on the rolling road about 1,000 miles ago and various garages and specialists and other trackday goers over the years have told me that xflows always breathe heavily. I'm not saying ignore it, but don't assume the worst just yet Bob

Can't help with the diagnosis but you are pretty close to Redline in Caterham (Grahame Of 7 Indulgence in Meopham has stopped the car business now and don't think Jon is looking for new Seven customers - mainly doing moderns) Bob

Mark, could well be worn. The engine came from Poland without history via eBay 😬 but seems in good nick and works fine Roger - yep, they cut cost everywhere! There's fuel in there alright but I assume something is causing an initial internal blockage?

Not on the Seven - it's the Weber 28IMB fitted to our '66 Fiat 500. When the car has been left for a few weeks it will simply turn over but not try to fire. Spark etc. is all fine. What I end up doing is removing the only external jet on the carb (think its the idle jet) and spraying a load of carb cleaner in. That's enough to get it to cough. Do that 3 times and it starts and then runs fine... If you then leave the car till it gets properly cold again it all works fine on the choke ('cold start mechanism' on these carbs). Leave it a week or so and you're faffing around with screwdrivers and carb cleaner again. There's no accelerator pump so you can't just pump the pedal as you do a DCOE. I can't believe they were like this new so does it sound like something obvious to the experts? I'm wondering if it's just worth investing the money in a new carb... Th other thing to mention is that it's a 650cc engine from a later Fiat 126 and the carb has a fuel return not present in the original car so the tank isn't designed to take it. I've simply run this back to in front of the fuel pump and fitted a non-return valve to stop it draining to the tank and creating an airlock. Don't think this is the problem as it runs fine once coaxed into life but prepared to be corrected . All help welcome! Bob

Pretty much all I did was modify the existing strap by bending it and fixing it to the battery box base to suit the Powervamp's smaller size. And that's it Bob

My 1700 with a 234 is nearly 140bhp at just over 6,000rpm but is dropping as it heads towards 7,000... Probably better with a 244 as long as you have 3D ignition to keep it all nice and driveable.

Thanks Richard

Having installed an eBay Fiat 126 engine ( was a punt on condition ) into our Fiat 500 as a power upgrade ( a common swap ) there's clearly something not right with it. I've done all the fuel and ignition basics but it gets rattly and loses power as it warms up and I need someone more capable to look at it. Any recommendations for a garage local to Maidstone / Medway who could diagnose it and, if necessary, do a rebuild? Ideally I'd leave the car with them rather than pull the engine again ( bored of it now ) Bob

I think I can live with the extra consumption from moving up to a single weber 28 . Bob

Aha - that looks ideal. Thanks Stu Bob

This is for my Fiat 500 project. The carb on the new engine has a fuel return pipe but the 500 was never designed for this. Looking on the web for similar scenarios the general consensus is to just blank it off, but what's the best way to do this? I can't find an obvious plug available, unless a suitable bolt would be adequate to do the job? Bob