Mechanical expertise

Technical Area Engine, Transmission, Exhaust etc
2

Hi all, 

I wanted to share my mechanical expertise. I am an owner of a 2001 1.6 mx5 and all my mechanical expertise is crying out and telling me that there is a slight vibration / raspy noise between 18-22 mph. Also changing gear from 1st to 2nd can be a little sticky when cold. Ok, down to my mechanical skills. I know that there is a round thing on each corner and inside the cockpit is another round thing that operates these round things. A my feet are 3 pedals that make the whole car go forward, reverse and stop. Oh and on the rear side near the round thing in the corner is a hole where the motion lotion pours into. So there it is. I’m an expert. 

Can someone assist me and say the vibrate / raspy grunting noise is common and I need not worry, and that when changing gear that to is also common and need not worry. 

Thank you for your patience. 

3

Your expertise is on a par with mine!

The sticky 1st/2nd gearchange seems to be a commonly complained about issue. Not so much of a fault rather a characteristic. Changing the gearbox oil seems to have helped some people but I’ve just got used to it on mine.

The vibration/rasp could be exchaust/mounting or shields rattling though? My old Ford Focus made a buzzing rasp at a very specific speed and it was the heat shield over the catalytic convertor.

4

Thanks, I’ll take it to a mate in a week or so. I will also need brakes so he can have a good look. 

5

The prime suspects are the manifold heatshield and the catalyst heatshield. Both can be quietened down with a tack-weld or two, but that will require someone with a deft welding hand as it’s pretty thin aluminium. If it is the manifold heatshield, a big exhaust clamp around the lower joint often sorts it for a while too.

6

I think you mean steel with an aluminized coating?

7

I’m sure I do. What I really mean is that your average welder will suck air though his teeth before deciding if he wants the job…

8

Thanks guys. I will take it to my mate and hopefully make it sound as nice as it makes me feel when I drive it ??

9

Common rattles:

  1. 2100rpm - window winder spring (on UK cars).  Also tends to rattle with low bass notes on the stereo (2100rpm = 35Hz)

  2. 3500rpm - catalyst heat shield

The stiff 1st - 2nd change is completely normal.  Redline MT90 gear oil is said to help but it didn’t make a whole lot of difference to my Mk1.