Oil change basics for a DeLorean

Parts and Tools
Procedure

Parts and Tools

7 quarts of oil
oil filter
copper washer for drain plug (see note)
oil drain pan capable of holding at least 8 quarts
filter wrench
drain plug tool
jack and jack stands

Oil - Ask a group of auto enthusiasts about what oil to use and prepare to hear a different opinion from every person who answers. This is one of the most hotly debated topics on any automotive discussion board. My own take on this is to use any good quality oil in the recommended weight range and change oil at reasonable intervals. I personally use Castrol GTX 10W-40 and change it every 3000 miles or twice a year, whichever comes first.

Here are the recommended oil weights from the owners manual:

 Most of us are going to fall in the middle group which is why I chose to use 10W-40 in my car.

Synthetic vs. conventional - This is a hot topic, and I'm not going to get in the middle of it. I will say that I use a conventional oil in my DeLorean, but use Mobil 1 Synthetic in my other vehicles. Just use a quality name brand oil no matter which type you choose and you shouldn't have any problems. The chart below shows the pros and cons of each type:

Oil Filter - If you have any doubts at all about the various cross reference filters, just order yours from one of the normal DeLorean parts vendors. They handle only the original equipment filter so you know it will fit, and the cost is not that much more especially considering that most people will only change oil twice a year.

On the other hand, if you have worked with cars for a while you know that there are other after market manufacturers of quality oil filters. In the DeLorean, some fit exactly like stock, others require a fitting to move the oil sending unit. These are usually the filters designed for the Volvo applications of this motor. The DeLorean added a large diameter sending unit right next to the filter so that the Volvo oil filter will hit it. By adding a 45 deg brass elbow you can offset the sending unit and use the Volvo filters. Below are a couple of the known cross references, but there are a lot of other ones.

Purflux LS410C (factory filter - this is the one that the vendors sell)
Napa 1342
AC PF2140
WIX 51307 (wider Volvo type)
Purolator L14670 (wider Volvo type)
Fram - avoid these as the quality has dropped considerably in the past few years. DMC-Houston has a picture showing a cut open Fram as opposed to the OEM Purflux.

Don't assume that just because the Fram filter is junk that all aftermarket filters are bad. Purolator makes a very good filter, especially their premium line. Wix is just as good and is also sold under the Napa Gold line.

The 45 deg angle fitting mentioned above is a Weatherhead 3350X2 from Napa. I'm using one of these with the Purolator filter mentioned above, which is the recommended filter for the Volvo PRV6.

Copper washer for drain plug - All of the DeLorean parts vendors stock these. I'm told that PJ Grady sends one along with each oil filter purchased. The washer is used to seal the drain plug. You can use the washer multiple times (I have done this successfully), but don't blame me if you have an oil leak. An Oil-Tite brand #65273 is supposed to work, although I haven't verified this yet.

Oil drain pan - Nothing special here other than to make sure it has enough capacity. The DeLorean contains more oil than many American and Japanese cars. Make sure the pan will hold at least 8 quarts.

Filter wrench - There are different types on the market. The best are the "cap" style wrenches that fit across the end of the filter and are turned using a 3/8" drive ratchet. But, you have to have the right one for the filter. If you use the same brand and model filter every time just get a wrench to fit and you're set. Watch out on your first oil change in case the filter on the car is not the same as the one you bought the wrench for. In this case, or to be prepared in case you use different brands of filters, you can use a generic strap style wrench. These have a band that goes around the filter and it is tightened by pivoting the handle. There is enough room in the DeLorean to use one of these, but it is more difficult than the cap type wrench.

Drain Plug Removal Tool - The DeLorean drain plug has an 8mm square hole in it instead of a hex head like most plugs. The DeLorean parts vendors stock a Snap-On brand adapter PPM410A or PMM408A that fits a 3/8" drive ratchet and has the square end for the plug. This is the best way to go. The tool costs about $20, but it will last a lifetime. (Note: the PPM410A listed above is a 5/16" tool, and the PMM408A is an 8mm. Both will work fine as the two sizes are virtually identical)

You could also make a tool for this, but it takes some minor mechanical know-how to do it. Get a piece of 5/16" square stock about 12" long from a hardware store. (5/16" is around 7.94 mm, so it will work great in the 8mm hole). Place one end in a vise and heat the stock with a torch about 3/4" from the end. When red hot, bend it 90 deg to form an L shaped tool. Cool in a bucket of water. Or cut a short piece of the stock and JBWeld it into a 12pt socket of the right size. Alternatively you could take a short 3/8" drive extension and grind it down to make a tool similar to the Snap-On item. Personally I recommend spending the money to buy the tool. Snap-On has a lifetime guarantee, and I've always considered tools to be an investment.

Note: Special T Auto sells a replacement drain plug that has a regular hex head so you can use a standard wrench on future oil changes. I also saw about the same thing locally, so you may want to take your old drain plug to the local auto parts store and ask if they have one.

Procedure

Once you have all the parts, run the engine for a bit to get it to operating temperature and also to circulate the oil so that all the crud and dirt will get suspended in the oil and will drain with it. Try to get the oil draining within about 10 minutes after you stop the engine or some of the dirt and contaminants will settle to the bottom of the oil pan and may not come out.

You could put the car up on ramps, but I find it works better to just use a jack and jack stands. You don't need to lift the car far unless you have lowering springs on it. I have done an oil change on mine without even jacking it up, but it was a tight fit.

However you do it, just BE SAFE!! and use quality jack stands. Never get under a car with only a jack supporting it!

Put a drain pan under the car's oil pan and take out the drain plug. The plug faces the front of the car so you can't see it unless you get under the car. Use the adapter you bought to remove the plug. Once the oil has drained to just a trickle, clean the plug off with a rag. Look for the copper washer. It may still be on the plug, or may have stuck to the oil pan, or it could have fallen into the drain pan. Locate it and/or remove it and put the new one on if you bought one, or clean the old one if you choose to reuse it. Screw the plug back in and tighten. Snug, but don't over tighten as stripping the threads would get *very* expensive.

Remove the old oil filter. It is on the right side of the engine next to the alternator. Very easy to get to and easy to spot if you just look up while under the car. If you are new to changing oil, then I recommend an original type filter for this first time. After that you can consider some of the cross-reference filters if you want to. But if you want to be absolutely sure of things, just use an original every time. It's more expensive, but not by enough to really matter.

Anyway, remove the old one. Have your drain pan under it as it will leak oil. Wipe the sealing surface at the engine block off with a rag to remove any dirt. Dip your finger in one of your new oil bottles and smear a light coating on the gasket of the new filter. This lubricates it so it doesn't pull off while tightening. Screw the new filter on. It should be hand tight. Not too loose, but don't put a wrench on it and really crank or you won't get it off next time. The instructions I've seen sometimes from the filter manufacturers is to tighten the filter 1 to 1-1/4 turns after the gasket touches the engine block.

That's it under the car. Before you move up above, first verify that the drain plug has been installed and tightened, and that the filter is installed and is hand tight. Then lower the car and put away the jack and jack stands.

Add the new oil. The filler is on the left side of the engine and doesn't look like most fillers. It is the thing sticking up with a couple of hoses running into it. It just lifts out. The engine should take right at 7 quarts of oil with a filter change. I usually add a little over 6.5 quarts, then start the engine for a couple of minutes to fill the filter. Then, turn off the engine, check for leaks at the filter, and use the dip stick to determine just how much oil to add to top it off properly.

Just be careful when you are under the car. BE SAFE! And double check yourself on things like putting the drain plug back in. Always check for leaks after running the engine for a few minutes.

This write-up is adapted from a posting I did for the DeLorean Mailing List. I have tried to ensure that all of the information is accurate, but please do not hold me responsible for any problems that may develop. If you have any doubts about your ability to perform this procedure you should take the car to a competent shop and let a professional handle it.

© 2001 - Mark Noeltner and the Mid-State DeLorean Club