Chris's new build of an MX5 based car

[CTWV50]

Originally Posted by Ianr

Any idea what your voltages are Chris, I know this may sound daft but it seems to me you have a voltage drop, perhaps a faulty earth somewhere????
Ian

yeah I think there is a drop in voltage might try a few tests tomorrow. But with the time delay of around 10-15mins I think the lower voltage is highlighting a weak coil pack when it gets warm. But could be a faulty alternator or regulator. hmmm

[TheArf]

It's all down to that electrickery stuff it don't play fair, unlike mechanical trickery, it hides out of sight.

arfon

[CTWV50]

So this morning I had a look at the coil packs and they seemed fine no bad connections or anything, removed the fuel pressure gauge and then fired it up, then I turn it off and put the spark leads in the correct order! Measured the voltage at the battery 14.4v turned on the lights 13.5v, rear fog and main beam and I was dipping into 12v territory. Thanks for the tips everyone my finger was hovering over the "buy it now" button for some coil packs last night, I did check the earths, but I was paranoid about good earths when wiring up the engine and the earths were solid.

Going to take the 1.8 alternator off the 1.8, change the pulley on the alt or the 1.6 engine pulleys and see how I get on. No money spent and a easyish solution.

[CTWV50]

Stripped down the front of the engine, nose off, etc. No sheared bolts fortunately, but the crank ribbed pulley is chemically welded to the toothed crank pulley behind. I've t*****d it lots but have given up for the evening and left it soaking in WD40. If it still stubborn in the morning I'll be using fire. Oh and I've caused a leak from the water pump inlet so I'll have to fix that too!

[CTWV50]

All fixed, managed to get the crank pulley off this morning and fit the 1.8 pulleys, this evening I got the 1.8 alternator in and everything back in the engine bay including fixing that coolant leak from the rotted 6mm pipe I disturbed, it was going to go eventually anyway.



I now have a steady 14.4v with the lights on or off which is much better than before. 1.8 alt is bigger and needs a larger ring connector which fortunately I had. ribbed belt is a better design too so it solves the v-belt 1.6 issue aswell.

Nose on in the morning and then fit the 300lb springs and take it for a drive I guess!

[TheArf]

Better to have found the perished hose at home rather than on the side of the road

Arfon

[Ianr]

Originally Posted by CTWV50

All fixed,

Nose on in the morning and then fit the 300lb springs and take it for a drive I guess!

I'll be interested in your feelings about the 300lb springs, I've eaten a few more pies than you and have 250lb fitted
Ian

[wylliezx9r]

Originally Posted by Ianr

I'll be interested in your feelings about the 300lb springs, I've eaten a few more pies than you and have 250lb fitted
Ian

Yes let us know what the ride is like, it's not so much a weight issue with me it's the way the back end rolled on a recent track day.

[CTWV50]

Got it all back together, engine issue is resolved Rev cleanly all the way 7k every time now. Springs have reduced sag yet maintained grip in the corners. Walking as I type so excuse any errors. I did manage to clip my number plate though and rattle a wheel arch loose! The list continues !

[norton]

Hi,

I've read through your thread (great read and very useful) but, an I probably missed it but what brand bodywork did you use?

Cheers
Gav