Your Capri thrives on regular oil changes; it is the blood of the engine and many a clogged artery was caused by lack of this most basic care. The overhead cam engine has a spray bar which squirts oil over the lobes of the cam. If the oil is old and has particles in, it is possible to block up one or more of the spray jets and the resulting cam lobe will run dry and ultimately wear down.
Before changing the oil, the engine must be warm. I find driving round the Car Parts shop to get the oil and filter is just about fine. Jack up the front of the car making sure that the hand-brake is on and the car is on level ground. Always use a second method of support which should ideally be some axle stands. Other people use a stack of bricks or the spare tyre, but which ever way be sure that if the jack collapses the car won't squash you flat.
You will need an old washing up bowl handy to collect the oil in. Crawl under the front of the car and locate the sump bolt at the very bottom of the engine. Depending on who tightened it up last time, it will either be easy to remove or next to impossible. Remember that the oil is very hot ! Slowly undo the bolt until you can get it turning with your fingers.
You can tell when you reach the end of the thread as the oil will start to ooze out. Hold the bolt in place until it is obviously undone. Quickly move your hand away and if you're fast enough you will not get any oil on your hands. Hope that you had the basin in the right place!
While that is draining, we can concentrate on the oil filter. They don't come any more accessible than on the Pinto engine. Unless you are tall like me, you will probably need to drop the car down off the jack to reach it. If you have strong hands, you should be able to grab the oil filter and unscrew it (anti-clockwise). This is often very difficult especially if a garage fitted the old one. There are many gadgets available to help you undo oil filters, but the easiest way is to take a screwdriver and tap it through the casing of the filter using a hammer. This is quite easy to do as the metal is very thin. Use the screwdriver to lever the filter loose. There will be lots of oil everywhere, so make sure your basin is down below. Once the filter is unscrewed, drop it carefully into the basin.
At this point, pray that you remembered to buy the replacement filter ! Take the new filter and wipe some clean engine oil around the rubber seal. Wipe away all the oil from the area where the filter sits, and attach the new one.
The rule here is turn until you contact the gasket with the fitting, and then make a further half to three-quarters of a turn. It should be tight but only hand tight, if that makes sense.
Don't forget to put the sump bolt back before adding the new oil ! Again it should be tight but don't go crazy. The oil will be easier to add if you have a funnel. I use the top half of a plastic pop bottle because I'm too tight to buy one. The LASER Capri take 6.5 pints of oil.
I suggest that you use 10 - 40W motor oil which is recommended by Ford. This oil is thinner when cold which makes winter starting easier. If you have a high mileage car that burns oil, you should use thicker oil such as 20 - 50W (e.g. Castrol GTX) that will tend to stay in the engine rather than work its way into the cylinders. Fill to the top mark of the dipstick; any more is wasting oil because the car will simply burn it up quickly. Make sure to re-check the oil level after the car has been running because the oil filter will soak up nearly a pint on its own.
Finally, please remember to dispose of you oil responsibly. Nearly all Public dumps offer a drop-off facility. Don't dump it down the drain; believe it or not they go straight into our Rivers !