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1978 Triumph Spitfire 1500

Basic Maintenance - In-Situ Project

So, the first thing that needs to be done on any In-Situ project is to catch up on the basic maintenance that's necessary for the vehicle. Now, this project's basic maintenance will be spread out for a couple areas because of the amount of work needed. Generally speaking, this step is intended to make sure that the vehicle will safely operate and you won't accidentally do further damage to the car by driving it. For full documentation on what I target for the first maintenance phase, you can read the general article on In-Situ Maintenance. For today, in terms of basic maintenance we'll target the engine oil, transmission oil, differential oil, and fixing the speedometer.

Changing the oil

First things first, I've taken the oil fill cover off of the valve cover. When you do this take the time to look inside the valve cover. You want to look for tell tale signs of trouble such as excessive oil burn on the parts or white foam (indicative of coolant and oil mixing)

Put the front of the car up on jack stands. As skinny as I am (or these days, was) this car is just too close to the ground to get underneath. On the left-hand side of the oil pan you can see the drain plug. Before taking it out and draining the oil, use a good cleaner (like simple green) to clean as much of the crud off the oil pan as pssible. By getting this clean, it'll help you trace whether or not there are any oil leaks. Once clean, set your oil pan underneath the car and remove the drain plug. Make sure to check the drain plug for damage or wear before replacing it in the car.

Now, this being the first time I've changed the oil filter on one of these Triumphs I was worried about it dumping oil all down the side of the block like my sister-in-law's stupid Honda. As it turns out the British engineers were much brighter than the Japanese. No oil dump. I don't know the specific wrench size of this filter as I use my universal filter remover to get them off.

Here's the oil filter mating surface on the block. The nice little channel at the bottom of the opening is the reason why the oil filter cleanly drains when you drain the oil out of the bottom of the car. In the center you can see the original spin on shaft for the oil filter. This car hadn't been modified yet, so this spin on is the original factory size which doesn't match up with modern oil filter spin on diameters. If you want to keep the car in it's original form here you'll have to spend extra money for oil filters that mate up.

Now, what we're going to do is install a modern adapter instead of retaining the original. Here you can see where it's been removed from the block.

Here, after being removed you can see the difference in diameters from the engine side to the filter side.

For around four dollars you can get this adapter from It'll allow you to use modern (and much cheaper) oil filters.

Here the adapter is spun into the block. Just spin it on with your hands, when you put the new oil filter on it'll force it to do any final seating.

Once the adapter is in place, spin on the oil filter. Now, the newer oil filters are a greater diameter than the old ones. I've noted that the oil filter has little clearance around the air pump. You may need to use some oil filter pliers to tighten it down all the way.

Now that the oil has been drained and the oil filter has been replaced it's time to refill the oil. The car uses ~5 quarts of 20W-50 motor oil.


The differential on the Spitfire 1500 differs from earlier models. On the earlier cars the diffrential contains a drain plug. For this model they deleted the differential drain plug. I don't necessarily like this "design improvement" but they didn't ask me. So, you're not supposed to drain the differential, just simply top it off periodically.

Here's my filler rig. Rather simple really. The differential (and also the transmission) use a Hypoid 90 gear oil. The stuff works well, but I have to admit it's smelly stuff. One of the few car related smells I actually don't like.

Here's the fill plug on the differential. It's on the upper left side of the assembly. Clean/scrape as much of the gunk from around the area as possible so that you don't accidentally get any of it into the differential when topping it off.

Once the fill plug is removed, stick whatever fingerwill fit into the plug hole. You'll want to use it as a "dipstick" to determine the oil level inside the assembly.

Now, this differential didn't require much extra oil. Here you can see th oil rig plugged into the hole. A good squeeze on the bottle put just the right amount of oil into the differential. Once appropriately fille reinsert the fill plug and make sure it is tightened appropriately.


The guckiest part of this car is the transmission. I have to admit some fear around the condition of this unit. I hadn't been able to determine exactly why this transmission is so heavily covered in grime and gack.

On the forward right hand side of the transmission is the fill plug. Loosen the plug, but don't take it all the way out. I discovered on my car that the transmission had somehow been overfilled. I pulled the plug completely out of the assembly before draining the unit and it made a great mess all over me.

Here you can see the lower drain plug removed and the unit mostly drained. The oil in this unit was rather nasty/scary. I have no idea when it was last drained, but the smell indicated that it hadn't been drained in a really long time.

Here's some additional cause for concern. The drain plug on the Spitfire has a magnet embedde in it to capture metal bits that have been worn off the moving assemblies of the transmission. You can se that there's a significant amount of material clinging to the end of the drain plug. Here is where I wish I knew how many miles ago the oil had been changed. If this is from the first 40,000 miles the car has driven it's not too terrible, if this is from the last 1,000 miles it's driven, then it's time to be ready to rebuild the transmission. Because of this wear we're going to note the mileage at the change (which happens to be 48,394) and plan on changing the oil again at 500 or 1,000 miles to check for new debris on the magnet.

When it comesto refilling th transmission I find that an extra set of hands makes a huge difference. I used me same filler kit from the differential. If you run the fill line between the firewall and the tranmission and connect it that way your assistant can stand next to the car holding the oil bottle to fill the car while you can lay underneath watching for when the unit is full. Once it starts dribbling back out the fill hole, the transmission is full. Remove the filler and replace the fill plug.

Speedometer cable

Now I don't technically include this at this point in my general maintenance discussion, but since we're already working in the area, we might as well do the necessary repairs.

Here you can see why the original cable no longer works. We're looking at the point where the speedometer cable mates up with the transmission. The piece of steel sticking out from the center is the remains of the speedometer cable shaft. The old cable had snapped just outside the cable mating point. I pulled out the remains using a pair of needle nose pliers.

Here is the new speedometer cable installed. It's held in place by the clasp and bolt. Obviously, when removing the old cable you undo the bolt, drop the clasp and bolt, and then pull out the speedo cable.

The speedometer cable fits through the firewall at this point. Make sure to replace the rubber grommet if it's no longer usable. Never feed cables or wiring through the chassis without having a rubber grommet in place. It'll save you a lot of grief later when you try to fix the results of the chafe that would occur without it.

Feed the cable through this mess under the dash. It always helpt to note the route the original one ran to make sure it doesn't interfere with other items or risks being kinked.

The cable attaches to the back of the speedometer through the center plug shown here. The modern replacement one snaps into place. You may need to wiggle the spedometer cable a bit to get it to fully seat and snap into place.

Now we've done th basic maintenance for this project. Next it's a matter of going through the suspension and refreshing the necessary bits.

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Contents copyright 2008, 2009 - Jody F. Kerr

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