Friday, September 18, 2015

The First Engine Startup

<This post is part of the 'Engine Swap' project>
Well it’s been a long and (for me at least epic) journey over the last year, slowly building my new engine. Learning as I went, making mistakes, fixing them, making more mistakes, fixing them also, but finally I’ve arrived at the big day; the day it hopefully comes to life!!

I’m as nervous as hell, but before I can turn the key, there are a few last minute jobs to sort and then a final checklist and it’s time…

So, things still on the ‘TO DO’ list are:
  • Install the new spark plugs
  • Torque down the head properly
  • Set the valve clearances
  • Check everything
  • Check it again
  • Take a deep breath
  • Turn the key

Install the new spark plugs
Obviously if you are going to the effort of building a new engine, it’s only good and proper to install new plugs. I got these plugs on eBay from a seller called carpartssaver, they are NKG BP6ES and are perfect for my little 998 engine.

In the past I've gone for a similar spark plug, but with three ground electrodes instead of just the one and they have performed very well, but this time I thought I’d give the single ground electrode type a try.

Installation really couldn’t be simpler, I removed the old spark plugs that I'd put in to keep the muck out and screwed the new ones in. I always make sure that I don’t over tighten them as the thought of destroying the threads in the head makes me shudder!!

As I made sure my HT leads were labelled beforehand, it was just a simple job of putting lead 1 onto plug 1 and so on. If I hadn’t labelled them, it’s not the end of the world as the internet will always come to the rescue, but here is the firing order and how to attach the HT leads anyway.

Torque down the head properly
Unfortunately one of the disadvantages of using the hoist with the load leveler, is that attaches to the head studs. This means I wasn't able to torque the head down before fitting it in the car.

Now the engine's in though, it's time to get it all torqued down properly. As always, I follow the instructions in the Haynes manual for torquing the head down. The method I've used here was exactly the same method I used the last time I had the head off in this previous post.

Setting the valve clearances
With the head now secured, the valve clearances now need to be set as per the spec in the Haynes manual of 0.3mm for my engine. Again this article here details how to do it. What I will add though is that this time I used the front wheel to turn the engine as it was a lot easier than using the fan belt.

This method, I picked up recently, involves jacking up one of the front wheels off the ground ansd putting the car into 4th gear. Now ensuring the main HT lead is off the coil (so the car doesn't start accidentally), the engine can easily be turned over by simply rotating the raised front wheel.

Once everything was checked and checked again, there are a few important things that need to be done before starting an engine for the very first time, especially if a new cam is fitted. I read that the first five minutes of a new engine's life are critical so it's important to get it right.

I have spent quite a lot of time searching the internet and reading as much as I could about the subject to arm myself with the necessary knowledge before I turned the key. I came across a number of things that were useful, but this link seemed to summarise everything into one handy document.

The main things that need to happen are;
1) The engine fires up as soon as possible and not be constantly cranked on the starter.
2) Once it fires, it needs to be run up to about 2000 rpm as soon as possible to make sure the oil pressure is nice and high.
3) DO NOT let the engine idle. Nearly all the documents I read seemed to stress the importance of this.

To this end there are two things that will help make sure everything goes as smoothly as possible. The first is to make sure that the oil system is properly primed. Priming the system ensures that there are no air locks or blockages in the system and enables the oil pressure to maximise as soon as the engine starts to crank. I have previously primed the system while it was still sat in the house at the same time I installed the oil pressure gauge in this post here.

The second thing that will help the engine fire asap is to refill the carb float bowl with fresh fuel. As there are only 3 screws holding the float bowl lid in place, it's a pretty simply a job of removing them and pouring in a bit of petrol.

Starting the Engine
After all the preparation is done and everything is checked again, the time comes when you have to sit in the seat and turn the key. It's a nerve-wracking moment and no mistake, but I took a deep breath and did the deed...

The starter cranked for a nervous five seconds or so and I stopped to give it a rest, another deep breath and a turn of the key, this time assisted with a little press of the accelerator. Another nervous few seconds passed, then the engine spluttered a little, gave a small chug and then BOOM, it came to life with a dirty great plume of smoke as the engine assembly lube was burnt away.

Using the choke, I set the revs to about 2000 rpm as soon as possible and got out to have a look at the engine as I couldn't quite believe it was working. Here's the special moment...

During the first five minutes that the engine was running there was an interesting collection of smells and smoke from here and there as the engine heated up all the new components. This soon calmed down though and after 10 minutes everything seemed to be chugging along as quite nicely. All the time, I had my eye on the temperature gauge and thankfully it was perfect.

So that's that, I have achieved one of my life goals; to build an engine. The next is to drive the car powered by my own engine, can't wait.

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