Z Car Update

1972 datsun 240z wheel arch restorationAbsent any questions this month, I will give a brief Z car update. The car is a 1972 Datsun 240Z receiving a total restoration. The car had significant rust in the lower body panels and floor. The left side was much worse than the right side.

Work on the left quarter panel is progressing. The rusty inner wheel well was totally replaced. This involved drilling out the spot welds and removing the old panel. Fortunately, well made replacements are available. The new part was an exact fit. With the new inner wheel well in place, the repair of the outer quarter panel could proceed.

1972 datsun 240z wheel arch restorationWe obtained a Tabco rust repair panel. This panel is made of nice thick steel, but the fit is poor. I like to keep as much of the original car as possible. We went just above the rust, cutting the metal out, just above the rust area. We only cut out the rusty part of the quarter panel, and will weld in the replacement panel.

When fitting a weld repair, I do not like straight lines or sharp angles. I find it easier and stronger to have the weld seam a series of curved lines.

The repair panel was carefully trimmed to fit, and will be welded shortly. It will be spot welded along the wheel well, as original. I may also use two part panel epoxy, this will produce a much stronger, more weather tight bond than it had at the factory.

1972 datsun 240z

Editor’s notes….David and son, Sean, will have the Datsun 240Z at the Shelburne Show on Father’s Day weekend. A beauty of a car, as witnessed in the file picture to the left, is outstanding. Hiratsuka, Kanagawa in Japan is where they were built from 1970 to 1973. The 240Z was meant to compete head to head with the MGB-GT and won the race with its great de-sign and relatively low price.

Sounds Good – A Bright Idea

led headlightsOne of the headlights recently burned out on one of my Saabs. No big deal, this happens every so often. A set of premium brighter bulbs costs almost fifty bucks, and I have noticed they do not last as long as the regular bulbs. A pair of LED bulbs is only fifteen dollars more, and these will outlast the car. I decided to order the LED bulbs and try them. They are a direct fit replacement for the standard halogen bulb. Unlike many LED bulbs on the market, these bulbs are an engineered replacement for the incandescent bulbs.

On some vehicles, like my Chrysler minivan, the headlight needs to be removed to replace the bulb. This requires removing five bolts and takes time.

In addition to lasting much longer, the LED bulbs do not generate heat, takes far less energy, and you can actually touch the bulb without destroying the bulb. Interestingly, I noticed both old headlight bulb pigtails were partially melted when I installed the LED bulbs.

I will drive with these bulbs for a few weeks to make sure they work, at least, as well as the incandescent bulbs.

I bought these bulbs from superbrightleds.com. I am very impressed with their quality, selection service and price. They list replacement LED bulbs for virtually every bulb in the car.

Engine Management Upgrade

1987 saab 900The distributer in my 1987 Saab 900 Turbo recently broke. Even though it is a Bosch distributer, it is no longer manufactured and parts are not available. This distributer was only used on model years 1986 and 1987. I was able to find a used one; however, several people suggested I upgrade the engine to the later fuel in-jection and ignition system.

The fuel injection and engine management electronics on this car were state of the art, in 1987. Engine management technology improved significantly since.

Saab continued to use this same basic engine right up to the end, and the engine was updated to coil on plug ignition and an improved fuel injection/engine manage-ment system. By upgrading the engine, the engine performance was significantly improved, as was engine efficiency. I have been told to expect an extra 6 miles to the gallon, and an extra 40 horse power with the change to the later components. Another benefit is OBD 2 engine management. Diagnosis and repair of problems is easily handled with a universal OBD 2 code scanner, no more dependence on a Saab Tech II code scanner.

To make the change, I can either take the components off a newer Saab, or buy a conversion kit. The process involves removing the distributer, coil, electronic control module, and the various electrical components and installing the newer components with some extra sensors. Many cars from the 1960’s through the early 1990’s have engines that continued in production through the evolution of modern engine management. Upgrading these engines to modern engine management could be a fun project, with great rewards.

It’s in the Bag

When doing engine work or restoration work, organization is key to success. I recently overhauled an engine in my shop, and I was greatly aided by a careful and thoughtful organization when I took the engine apart.

I carefully catalogued the nuts, bolts, hardware and parts in zip lock bags, carefully labeled with a sharpie marker. The valve cover bolts were placed in a sandwich sized bag, labeled valve cover bolts, Left. The head bolts and miscellaneous hardware were placed in quart sized bags and labeled. These bags were then placed, in a gallon sized bag, labeled and Left.

This method continued through the engine disassembly. The oil pump bolts were bagged, and placed in the bag with the oil pump. All of the bags of parts were placed in a box with all the other parts.

When I reassembled the engine, all of the nuts, bolts and miscellaneous hardware were easily located, and the order of opening and unbagging the parts, easily gave me what I needed without wasting time searching, and minimizing the risk of placing the wrong hardware in the wrong location. When installing the left cylinder head, I grabbed the bag labeled Left, and all of the hardware was clearly labeled. When I was done, all the hardware was accounted for. There was nothing missing, and nothing left over.

I also use this strategy when I take a car apart for major work or restoration. There is nothing more maddening than not being able to find a part when needed.

Zip Lock freezer bags have an extra strong zipper, and provide a white rectangle for labeling. The next time you are in the grocery store, I would suggest buying a few boxes of sandwich, quart and gallon sized zip lock freezer bags for your shop.

Alternator Maintenance

I recently had a Subaru Outback in the shop for some extensive maintenance. I had to remove the alternator to do this work. The car had 185,000 miles on it, and still had the original alternator. I decided I would utilize the time waiting for parts to do some preventative maintenance, and overhaul the alternator while the car was in the shop. A rebuilt alternator for this car is about $200, with a new one over $400. The parts to overhaul this alternator were about $30.

How does one overhaul an alternator? Usually when an alternator wears out, it is due to the wear items reaching the end of their useful life. The wear items in an alternator are the brushes and the bearings. On this alternator, like many alternators, the brushes are part of the regulator assembly. While new brushes can be soldered in to the existing regulator, it is far easier to replace the assembly as a unit.

I ordered the parts on line. Surprisingly, I have found most parts stores do not sell alternator rebuild kits. I have to buy them from automotive electrical or electric motor parts suppliers.

An examination of this alternator revealed the brushes were well worn, almost at the end of their useful length. Both bearings rotated freely, however sounded and felt slightly “gravely” when rotated. The rebuild kit came with both bearings and a brush/regulator assembly.

Rebuilding of the alternator was very straight forward. First, I removed the drive pulley with an impact wrench. The pulley easily slid off. Next, I opened the case by removing the four bolts holding the case together. The front of the case came off after several light taps with a hammer. I carefully compared the old parts with the ones that came in the rebuild kit to ensure I had the right parts. Once the front of the case was off, I removed the four screws that held the front bearing plate on. These screws required the application of a torch to free them, but came out easily once some heat was applied. The front bearing came out of the case easily, with a gentle push from my thumb. The new bearing easily slid into position, and was secured with the four screws and the retaining plate.

The rotating assembly was removed from the case next. A careful inspection of the slip rings showed they were in good condition. There had been no arcing against them from the brushes. The rear bearing needed to be removed from the shaft in the press with a bearing knife and a drift. Great care is exercised to prevent damage to the assembly. The new bearing easily pressed on to the shaft.

The brush/regulator assembly is soldered into the case. I needed to melt the old solder connections with a soldering iron. Careful inspection showed the remaining parts of the alternator were in good condition. I carefully cleaned the alternator case while it was apart, rinsing all pieces with electrical cleaner.

I mounted the new brush/regulator assembly in to the case, and soldered the connections with electrical solder. The brush assembly came with a small wire to hold the brushes in place. It is important to leave this wire in place, and carefully thread it through the small hole on the back of the alternator assembly. It is impossible to mount the rotating assembly into the case with this wire removed, as the spring loaded brushes will interfere with the slip rings upon reassembly.

With the brush/regulator assembly installed, the alternator can be reassembled. After assembly, it is important to ensure the alternator spins correctly, with no noise or interference.

This is an easy and inexpensive preventative maintenance step.

More Questions About Oil

From the Editor….

Dave, would you please keep this oil discussion going?

Questions….. Should we use synthetic in our old cars? What about the question of single-weight oil vs multi-weight oils in our old cars, which is best and why? You have mentioned the moisture collecting in our car’s oil pans, especially during winter storage, should oil types come into the conversation here? What about this whole question of 600 weight in our old differentials? What should we use and is 600 weight really 600 weight? Thanks Dave.

Gary, good questions.

synthetic oil cansThe question of synthetic oil in our old cars is a good one. Like any selection of engine oil, it comes down to the application.

The quality of engine oils has improved dramatically since our antique cars were manufac-tured. The multi-viscosity high detergent oils available today are vastly superior to the oils availa-ble when these cars were new. Not that many years ago, engines were full of sludge and varnish from engine oil deposits. Cars needed to have the engines flushed with flushing oil during an oil change.

The additives and detergents in engine oils still break down, requiring oil changes. This happens more quickly under “severe” driving conditions. Older, carbureted vehicles with open crank case ventilation require more frequent oil changes. The fuel mixture of carbureted engines is not as well controlled as the fuel mixture of modern computerized fuel injected en-gines. Unburned fuel in carbureted engines and early fuel injected engines will dissolve in to the engine oil. Modern engines have sealed crankcases. Older cars have open crankcase ventilation, leaving an opportunity for dust and dirt to migrate in to the engine oil. Because of these reasons, oil needs to be changed more frequently in these older engines than it does in modern engines.

oil leakI have had a number of people tell me they will not use synthetic oil, because they think it will leak out. If your engine already leaks oil, this is true. Synthetic oil will not cause new leaks in an engine. If the engine has sound seals and gaskets, synthetic will not leak any more than conventional oil.

Synthetic oil is superior to conventional oil for lubricating and cooling the moving parts of the engine.

If the vehicle has a fairly new engine I would be more inclined to use synthetic oil. The parts and machining cost to rebuild an engine can quick-ly pass $5,000. Synthetic oil is a relatively inexpensive way to protect this investment.

Some vehicles, like air cooled Volkswagens, were designed to use straight weight oil. I have been told multi viscosity oils can foam up in these en-gines, and only straight weight oils should be used. I use straight 30 weight synthetic engine oil in my John Deere Tractor.

Moisture will condense in the crank case as a byproduct of combus-tion. This moisture will remain there until it evaporates away due to engine heat. The engine needs to be run for a while fully warmed up for this to hap-pen. If the car is not driven much, it makes sense to change the oil before putting the car away for winter storage.

There are many factors to consider when choosing an engine oil. The type of driving, number of miles driven in a driving season, the condition of the engine, oil consumption of the engine and cost of the engine oil should all be considered.

Ultimately, it is up to you to decide if the extra protection of synthetic engine oil is worth the extra cost.

Next month I will talk about gear oils.

Editor’s notes….. Watch the monthly VAE auction, you will find some great oil deals. Much of the time the price is half or less what you would pay at the store and the items are high quality, new products.

Synthetic Oil

Hey Dave’s Garage-

What is synthetic motor oil all about? Why is it better than natural oil? How does it differ chemically? I always thought that frequent oil changes were necessary because of the build up of acid and other contaminants. Why don’t they build up in synthetic oil the same way? Wendell Noble

Wendell, great question! There is a lot of information, and a lot of strong opinion here.

There are three types of engine oil sold in the U.S. that are considered “Synthetic”.

synthetic oilGroup III synthetics are oils based upon hydrocracked crude oil. They have many qualities of “true” synthetic oils, but they are not manufactured or “synthesized” in a lab. They are refined from crude oil.

Group IV synthetics are produced from Polyalphaolefin base stocks, and are one of the two “true” synthetic oils available in the US.

Polyalphaolefin (PAO) is a manufactured ethylene chemical used to manufacture many plastics and fabrics. It also can have good properties as a lubricant. Pure PAO alone does not work well as an engine oil. It still needs additives to work as an engine oil.

Group V synthetics are almost exclusively ester based. Like PAO based lubricants, group V base oil needs additives to be an engine oil. Group V based oils are very specific application lubricants. I don’t believe they’re used as a base in over the counter synthetic engine oil.

So, so called group III synthetics are a more highly refined crude oil, with a base stock that comes out of the ground as crude oil.

Group IV synthetics are synthesized from Polyalphaolefin (PAO).

The benefit of a true synthetic is uniformity and consistency in the molecular make up of the base oil. Unlike refined crude oil, synthetic oil has consistent molecular chains. Think of crushed gravel being ground up to similar sized pieces (conventional oil), and compare that to manufactured glass marbles (Synthetic). The marbles are more consistent in size and shape. The marbles would make a better lubricant.

Cost may be the best way to determine if oil is a true synthetic. If it is under $5.00 a quart, it is probably a group III synthetic. The true answer can be found on the bottle or the manufacture’s website.

Regardless of the base lubricant, all engine oils have additives to control viscosity through temperature ranges, and additives to keep the engine clean and well lubricated. These additives still wear out or break down regardless of the base oil used. Engine oil is also diluted with by-products of combustion through use.

So why use synthetics? Synthetic oil is a superior lubricant. The oil is consistent on a molecular level, with no impurities. Refined oil has inconsistent molecular chains and still retains trace amounts of impurities. Synthetic oil maintains viscosity regardless of temperature. Put a quart of conventional oil and a quart of true synthetic in your freezer overnight. In the morning take them out and shake them. The synthetic will still be fluid. The conventional oil will be thick like honey. Remember that next winter when it is below zero and you start your car.

Synthetic oil does not sludge and varnish in the engine as conventional oils do. I have opened up engines with over 200,000 miles on them with synthetic oil, and they look like new inside.

Oil change intervals should still be dependent on driving conditions. Short distance driving is “severe” duty. It is often a good idea to do a Used Oil Analysis to get an idea of when to change your oil. A UOA may show your used oil did not need to be changed, and was still able to properly lubricate. You may find a vehicle with synthetic oil, with few short trips can go 10,000 miles or more before the oil needs to be changed.

From the Editor…. Dave, would you please keep this oil discussion going?

Questions….. Should we use synthetic in our old cars? What about the question of single-weight oil vs multi-weight oils in our old cars, which is best and why? You have mentioned the moisture collecting in our car’s oil pans, especially during winter storage, should oil types come into the conversation here? What about this whole question of 600 weight in our old differentials? What should we use and is 600 weight really 600 weight? Thanks Dave.

Tank Ooze

gas tank oozeAbsent any questions this month, I will share something interesting with you. Recently I drained and removed the gas tank on the Datsun 240Z project. This car was parked in 1982. I removed the drain plug, but no gas came out. I poked at the hole with a screwdriver, and felt a thick tar like substance. I poked through it and very dark, varnished gas began to dribble out.

After removing the gas tank, I stood it up on end. About a gallon of thick, black asphalt like substance oozed out the filler neck.

I googled it, and learned that gasoline literally turns back in to crude oil after sitting for a long time. After 35 years, it does not resemble gasoline anymore.

Project Updates – MGB & Datsun 240Z

Absent any questions this month, I will give a brief update on the projects I am working on. The MGB project is progressing nicely. The front suspension has been rebuilt. All the metal parts have been wire brushed, cleaned and painted. The cast parts were painted with a coat of “cast blast” lacquer to replicate the look of clean cast iron. The steel pieces (brake dust shield, lower A arm and all hardware) were painted with POR black paint. This will provide a durable and long lasting paint protection.

1972 Datsun 240Z
The ’72 Datsun 240Z “Gift-wrapped”

The entire brake system has been overhauled. Many metal lines were replaced with Nickle-Copper lines, affording an opportunity to learn how to shape hard lines and how to create bubble and double bubble flares. All the rubber hoses were replaced. The calipers and master cylinders were rebuilt, and the shoes, pads and rear wheel cylinders were replaced. Brakes were adjusted and the wheel bearings were repacked with new grease seals.

The generator, distributor and carburetor were rebuilt. Last week the car was started, the first time it has run in 30 years. We let a mixture of ATF and Acetone soak in the cylinders for some time before we changed the oil. The engine turned over easily. The engine started right up, however, some of the valves were sticking. We let it run for about 20 minutes, then slowly poured seafoam into the carburetors. This week we will set the ignition timing, and adjust the carbs and the valves. We will also set the front wheel toe-in alignment using two parallel strings strung through the axle center line and a dial caliper. We will move on to the rocker panels and the floor pan replacement.

I have another project in the garage, my son bought a 1972 Datsun 240Z. This car has rust in the usual places. It is getting new rocker panels, floor pans and rear quarter panels. Fortunately, the car came with all the body panels. This car will be a father/son restoration project. The car is solid enough, but will probably end up being a full ground up rotisserie restoration.

The driver’s side floor and rocker panel have been replaced. Most of the rust repair on the left side has been completed. After the rear quarter panel is done we will test fit the front fender and the door, adjust all the gaps, then move on to the right side. Once all the welding is complete, the engine, transmission, front and rear sub frames, the front and rear suspensions and the rest of the interior, will be removed. The car will go on the rotisserie for all the body work and final painting. Stay tuned…

MG Update

I have not received any questions this month, so I will give an update on the MGB project I am helping the high school student with.

When we adjusted the valves, I was able to use my camera scope and explain how a four cycle engine works. The principle of the carburetor operation was easy to understand while rebuilding the carburetors.

I have taught her how to rebuild the brake master cylinder, the brake calipers, and the clutch master. I have taught her how to cut and form metal brake lines, make bubble flares with a flaring tool, replace brake pads and brake shoes, and how to adjust drum brakes.

Together we replaced the kingpins in the front suspension. Taking the suspension apart, I was able to show her how the suspension worked. She got hands on experience disassembling, rebuilding and then reassembling the suspension.

We disassembled the generator, soaked the bronze bushing in engine oil, dressed the armature, replaced the brushes, cleaned, paint-ed and reassembled it. We polarized it, then tested it before installing it back on the car.

More hands on experience was to be had when I walked her through how to replace the wheel bearings. She was able to knock out the old bearing cones and install the new ones. This was followed up with packing the bearings and installing new grease seals.

We even successfully banged out a good size fender dent. We may weld in new floor pans and rocker panels.

I am so impressed with how quickly she is able to learn new skills, and master these tasks. All through the project she is learning how to properly care for tools, and keep all the parts well sorted. We are carefully saving all of the old parts, and every work session ends with carefully wiping the tools down with a rag, then putting them away, clean.

The MGB is a great car to learn from. It is simple enough to use as a model for explaining and demonstrating how the systems of a car work, yet modern enough to be relevant.

We need to continue projects like this one to keep our youth invested in the hobby. In a few weeks this MG will be ready for her to drive it to school. Amazing, considering the car had been parked outside for years before she was born, and has sat idle her entire life.

mgb brake calipers

Yup, the calipers both looked like the one on the right, now they look like the one on the left. Cleaned, and new pistons, seals and dust seals.