Saturday, 27 March 2010

Putting it all back together

Well I have spent the day putting the Spitfire back together after last weeks gearbox and engine out. I have fitted a new Fuse box and re wired the reverse light as it grounded out on the 10CR causing the loom to burn through. Everything sorted and the bonnet back on I have put the battery on charge to enable me to give her a run tomorrow.

Some bad news, In June/July last year someone reversed into the rear of my Spit dinting the rear bumper. I took it off today and tried to knock the dint out. No luck the Chrome has cracked so the bumper is staying off until I can get a replacement or get this one repaired and re-chromed.

I am going to wash the car tomorrow and I am off to the Lake District on Monday.

I hopefully will have the car sorted for good Friday when I hope to take her to the P&P meeting.

Fingers crossed with no gearbox leaks.

Tuesday, 23 March 2010


Well after finishing my Exam and having a little more time on my hands I managed to do a little on the Megasquirt assembly. Well to say a little would be an understatement.

I finished the board a couple of days after my exam which was on the 9th March, and after plugging it into the stimulator, I heard a little click and the computer refused to communicate with the Daughter-board (main chip). After removing the Daughter-board I checked the voltages on the mount finding 2.5volts where 5volts should have been!

Well after panicking and fearing I had burnt the whole lot out, I followed the trouble shooting instructions on the Megasquirt main site, I checked all the build steps one by one and found nothing. So I went onto the Megasquirt Forum, where it is clear I am a novice at this, The fella I bought the kit from asked if Diode D19 (Capacitor 0.1µF 50V 10% CER RADIAL - X7R) was getting hot! Sure enough it was.

His suggestion was check all the board for bridged solder joints and replace Diode D19.

On checking the board out with a magnifying glass I found I had bridged the 12volt and the 5volt lines on Q1 which a (field effect transistors, used to drive the injectors) It was only a very very small bridge but this had burnt out D19 which regulates and protects the 5v circuit.

Now the tricky bit, get hold of a (Capacitor 0.1µF 50V 10% CER RADIAL - X7R) Maplins did not stock this item; other sites sold them but only in the 1000's. But as always I turned to EBay and found them in a shop in Japan. £2.99 for 50. They were only available in 50's so at three quid I placed the order.

Well I am pleased to say the Capacitors arrived today and I fitted the 1 needed and hey presto a fully working Megasquirt.

I have tested it on the Laptop with the Stimulator and all seems fine, I have loaded a basic Map and injection table to test the board and all seems superb.

What a relief!


Saturday, 6 March 2010

Megasquirt/ Mega Stimulator

Ok After frying my brains with revision for what seems like forever I have taken a few hours break to clear my head. The Exam is on Tuesday and I can then concentrate on getting the Megasquirt built.

However I have managed to build the Mega Stim (used to check the Megasquirt as I build it) this was built the other night with a beer. (after 9 hours revision I needed a break) I was genuinely surprised with the quality of my soldering (much better than my previous work on the megajolt).
One thing I have noticed from the outset is the superb quality of the Megasquirt kit. It has clear labels on all parts and the quality of the board itself and the instructions are outstanding.

I have started to build the board and have completed steps 1 to 22, I have stopped whilst I figure out what IAC (idle air control) valve I will use and where to place this in my set up.

The IAC helps smooth out the start up sequence.

Pictures attached and as usual any questions or comments appreciated.