MX5 - NA6 Lifter Tick / Water Pump Tick / Exhaust Leak Tick

[Larseney]

Hi Guys,

I thought I'd write this down as I learnt something Valuable in fixing this particular fault with my MX5 that I hope might help someone else.

Last week I took my (Recently) Turbo'd MX5 to the Track. The Car has only done a few Hundred KM's with the Turbo Kit installed and Tuned, and also just had the Clutch and Coolant Re-route done.
The car ran amazingly at the track, like a totally different car. I couldn't stop smiling.
After 3 Sessions (18 Laps) the Engine started to "Tick".
Now the "Tick" was non existent at idle, and got louder with engine Speed (in gear or in Neutral)
Obviously I was worried!
I had a good look and listed and it appeared to be coming from the top of the engine at the Rocker Cover.
I initially thought "Lifters", so i went for a short run around the Track Paddock and did notice power was down bit, but couldn't be sure.
So, for better or worse I drove it the 100km home, very gently.

I then did as most of us would and took to the internet/forums for the Problem & solutions.
My top thoughts were (based on Research etc):
- Lifter Tick (lots about this on the net)
- Check timing, Timing Belt nay have jumped a notch on the Gear - noisy Cam Adjuster maybe too?
- Ticking Water Pump
- Exhaust Leak (Cracked Turbo Manifold or similar) - Exhaust Gasket is BRAND New, less than 1000kms

So I set about testing my Therories (Cheapest/Easiest to Hardest)

I Flushed and Changed the Oil and Oil Filter. I put Back in 100% Synthetic Oil, 5 - 30w and Nulon "Lifter Tick"
Tick didn't go away

I took off the rocker cover and checked the Timing belt on the Cam gears, the "I & E's" still lined up, checked timing, all good.
I also inspected the Lifters to look for Wear and to see of they all contacted the Cam Lobes, they did. I also pushed on them and they all freely depressed.

I had left the Water Pump as I would need to order one.

At this time I remembered that something had just slipped my mind from when I drove home from the Track. When i come off the throttle on the car normally the Wideband Guage goes to its Maximum Reading 22 AFR and obviously goes down to 10 - 14 when i'm on throttle.
Well, on the drive home it didn't, it stayed between 10 - 18, never maxing out.
This could have been significant, but i didn't realise it at the time.

Now I started to research what a Exhaust Leaked would sound like, some people did talk about a "Tick". But i have had exhaust leaks before, but I guess not one at the Manifold (where it joins the Block). I didn't really think this would be it! But, with the possible loss of power, the Tick happening with engine speed & the Wideband doing something different it did possibly suggest a Leak. Since it was easy enough to check I removed the Dump Pipe, Turbo manifold etc to get to the Exhaust Gasket.
Low and behold the Exhaust Gasket @ the outlet at Cylinder # 1 was black!
Exhaust Leak!
But still my mind can't seem to comprehend that a "Tick" like this can come from this!
I replaced my Exhaust Gasket with a 3 Layered solid Metal one, replacing the sort of Alloy "Golf Ball Pitted" one. I also used "Permatex Ultra Copper RTV Silicone Gasket Maker - Maximum Temperature" to seal it up.
I bolted it all back up and NO MORE TICK.

I am still so surprised at the cause of the Noise!
I would normally silently get on with life and working on the Car, but this event really surprised me and taught me lots of things.
I wanted to write this because the Symptoms lead me to lots of conclusions (one that almost had me remove all 16 Lifters to clean them as many Youtube videos suggest to do this)

If this helps one person, ever, GREAT!

Happy motoring!

Thanks to the this Forum for always helping me!

Chris

[93_Clubman]

...the symptoms lead me to lots of conclusions (one that almost had me remove all 16 lifters to clean them as many Youtube videos suggest to do this).

Indeed, very easy to draw incorrect conclusions because we crave certainty. However, until evidence from testing demonstrates otherwise, we need to accept uncertainty & entertain multiple possibilities as to cause.