Running in ailments

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Mucus72
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Running in ailments

I have a few queries after my first 2 weekends of driving, and now with about 300 incorrectly recorded miles on the clock!

1. Calibrating the speedo. I was heading the blat chain down the M1 in a 50 zone and I had complaints from the others later that I was only doing 40! How do I recalibrate the dial please?

2. Brake fluid leak. Basically the o-ring under the screw cap for the reservoir is about 1mm thick. After checking another 1 year older car with the same spec at the motor museum yesterday, his is at least 5mm thick and properly seals the unit. Quite simply the thinner ring will never allow you to screw down the cap tight enough. We checked another new build that has only driven one blat and it was leaking too. Mine leaked enough to strip paint on the side skin edge under the bonnet. Does anyone know the spec or part number of the thicker one please?

3. Duratec plus Mazda (quite wide, touches the chassis sides) gearbox vibrates the chassis quite a lot. After an hours drive my hands are fizzy and I can't feel them properly. My old K wasn't like this. Is this normal?

4. Maybe related to 3. The vibrations are enough that in this inaccurate 300 miles of driving both screws (which were tight) for the cam cover have undone themselves, disappeared and the cover was just floating on top of the engine. Now I know I can get more screws and use thread lock, but does this sound normal?

I'd appreciate thoughts and help as usual please!

marcus 

Jonathan Kay
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Calibrating the speedo. I was heading the blat chain down the M1 in a 50 zone and I had complaints from the others later that I was only doing 40! How do I recalibrate the dial please?

But it reads consistently... no variation at constant speed?

Two parts to this:

Getting the correction right

I'd check the observed reading against the values from a GPS device* at the speeds of interest to get a correction factor.

Changing the setting

Is it like the type described here? John Vine published a list of factors but the links are broken. I'd use a correction factor from your current value but you could also start with an absolute value like those.

Jonathan

* Not against fellow-travellers!

 

SM25T
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If the engine is touching the chassis ..... that's not right !!!
Jonathan Kay
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If the engine is touching the chassis ..... that's not right !!!

I was going to suggest going over all the engine and gearbox mounts, but this is more important. Where does it touch?

Jonathan

Mucus72
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Hi Ian,

what I meant is that the new(ish) Mazda 5 speed is a wide unit and although I centralised in the chassis when I fitted it, it was touching the silver heat reflective padded material on both sides of the transmission tunnel. I'm guessing that this may be the reason why I feel so much vibration. But not sure if it's all simply TADTS  

 

Mucus72
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Hi Ian,

what I meant is that the new(ish) Mazda 5 speed is a wide unit and although I centralised in the chassis when I fitted it, it was touching the silver heat reflective padded material on both sides of the transmission tunnel. I'm guessing that this may be the reason why I feel so much vibration. But not sure if it's all simply TADTS  

 

Mucus72
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Hi Jonathan,

speedo needle is stable, I just think it over reads. But it's a simple test I didn't think to carry out with a GPS at a few constant speeds. Will do that next time I'm out. Thank you!

ChrisC
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Now your car have passed the IVA switch to the race brake fluid cap, it has no holes and therefore can't leak even if inverted.

I found the caps can also leak if they have been over tightened once to many times (same as the coolant cap)

It means you wont have the brake fluid level warning light, but that's a small price to pay.      

Ian Mackenzie
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Hi Marcus

Nice to meet you at Gaydon yesterday.

Here is another race cap with the warning switch, but not sure if it will fit you reservoir: http://www.caterhamparts.co.uk/product.php?id_product=1714 

With the new speedometers, I think if you press and hold the trip reset long enough it should bring up the option to calibrate, get the true versus indicated speed ratio and adjust accordingly....

Cheers

Ian

MADMALC
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Over filling the brake master reservoir makes leakage more likely during spirited driving. Take some fluid out so the level is well below the top of the filler and it will help.

On the vibration issue it is worth checking that the steering column is not touching or nearly touching any part of the engine. Things can be a little tight around the UJ at the lower end of the shaft. The rack can be loosened and rotated to adjust the route the shaft takes.

Smile

R.I.P. SLR No.27.

Jim 123
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Marcus from my experience the latest Mazda 5 speed does contact the heat shielding along the inside of the transmission tunnel, but this may not be the source of your "vibrations".  I'd suggest you check the chassis longitudinals that run along the bottom of the transmission tunnel and see if there is a constant gap between the gearbox casing sides and the top edges of the longitudinals. If the clearance at any point is only a couple of m.m. you might be getting a touch condition when on the road.

Jim