Distributor rebuild

[Nordical25]

Hi everyone,

I promised to make this thread on the facebook page. I have rebuilt now several distributors and now it is time to tell how it's done since rebuilt distributors are getting harder and harder to find.

First question is why you would ever need to rebuild one. After asking this from myself I answer that there are two main reasons: oil leak inside distributor or broken bearing.

If this is not the case, partial rebuild may be just enough and it will be a lot easier. Read for further details.

[Nordical25]

You can start the procedure either with a distributor attached into the car or not. If the distributor is attached into the car, you may want to first put engine pulley mark in to 0. Then you mark current position of distributor adjustment screw in distributor housing. The screw has originally size of 12.

Then you want to remove distributor cap and check condition of both rotor and distributor cap. The distributor cap should be attached into distributor with 3 size 8 screws. You want to see especially if both rotor and distributor cap look a bit burnt. In this case you may want to replace them both. Replace burnt rotor before making any timing marks to it.

Then you want to create alignment marks both to rotor and to distributor so you can reinstall distributor into correct same position after rebuilding it. You need to watch two things when reinstalling the distributor: rotor position compared distributor housing and distributor housing compared to the whole engine assembly. Mark both of them properly before removing your distributor or take pictures of both positions when timing mark is in 0. Do not rotate engine between distributor swap because crankshaft rotates two times compared to camshaft. If you want to be 100% sure, make a mark to timing belt also when timing is 0 so you are 100% sure of correct position when reinstalling the distributor. Everything needs to be exactly in the same position when reinstalling the distributor.

You need to consider all this carefully before removing distributor so you won't cause extra headache when reinstalling distributor. If not, you will learn all this in a hard way.

[Nordical25]

After removing previously mentioned four bolts, deattach vacuum advance hoses. Mark carefully each hose and port so you won't mix them up when reinstalling distributor. There are three types of vacuum advances. If you are creative enough, you can swap into another version but more to this later.

Pull off the whole distributor assembly from engine and check outer oil seal of distributor. You can check condition of this seal by removing it. If you can't remove it without breaking it, you need to replace it or you will end up sooner or later with an oil leak.

Deattached distributor is shown in attachment picture.

[Nordical25]

Then you start rebuild by removing rotor. This is the most simple thing to do just pull it off. Then you may have some additional covers above coil and ignition coil module. They are very easy to deattach because they are attached to distributor without any screws. Pull them off by stretching every clip with a screwdriver. Afterwards your distributor will look like a shown example in the attachment.

[Nordical25]

Next thing to remove is ignition coil. It is held by two size 7 nuts and by four screws. Remove them and mark the exact order of wires before removing the ignition coil.

Replacing the whole ignition coil during distributor rebuild is highly preferred since these distributors are getting close to the age of 40 already. So you may want to order a replacement coil. Another replacements to consider are both inner and outer oil seals, distributor gear pin, distributor rotor, distributor cap, vacuum advance unit and distributor bearing. I will make list of preferred replacement items after rebuild notes.

After removal of the coil your distributor will look like this.

[Nordical25]

Then you want to remove reluctor attached to the shaft of the distributor. You can remove it carefully with flat screwdrivers. But them between reluctor and pickup coil assembly and twist.

Please note that reluctor is held on place by small shaft key. Don't lose it or you may need to make one during reassembly of distributor.

After removal of reluctor your distributor will look like this.

[Nordical25]

Then you can move on to remove ignition coil module and distributor wires. Ignition module can also break down so depending your size of wallet, you may want to replace this also but that is not necessary. It is fairly easy to remove because it is held in place by five screws. Three of them are attached into the wires and two of screws are attached into between module and distributor housing.

After removal of ignition module and wires, your distributor and will look like this.

[Nordical25]

Then you can continue rebuild by removing both distributor pickup coil and vacuum advance unit. They are attached into distributor housing by three screws. First you can start by unscrewing vacuum advance screw. After detattaching this screw you may want to try spin gently vacuum advance unit.

Then you can unscrew two pickup coil plate screws shown in previous post picture. They are ordinary screws.

After unscrewing three screws both pickup coil plate and vacuum advance unit should move freely. Rotate plate in a way that allows deattaching vacuum advance unit from it. Then you have succesfully removed all easy removal parts.

Afterwards your distributor will look like the one shown in picture.

[Nordical25]

Now starts the harder part, which requires bearing removal tools, drill and a bearing press.

First you need a power drill to remove original pin holding distributor gear. Mark carefully gear position compared to rotor position if you want to reuse these marks for resetting distributor correctly before drilling the distributor gear pin. It is challenging to drill but I have succeeded several times. Just make sure to use right size drill.

Then you need to pull distributor gear from shaft. You can use different tools for this. A big hammer and screwdriver will do the job in a good workbench. You may want to lubricate shaft before gear removal so you will minimize damage to distributor shaft when pulling of the gear.

[Nordical25]

After removing succesfully the distributor gear it is time to pull off shaft from distributor housing. You can do this easily in a workbench by applying force to distributor shaft end next to gear. You can also be creative and use a hammer and a beverage case.

[Nordical25]

After pressing or hammering shaft out of housing you have basically everything apart excluding distributor bearing and inner oil seal.

Sometimes bearing is attached to shaft and sometimes to housing after pulling the distributor shaft apart from distributor housing. Therefore removal of bearing can vary depending end result of distributor shaft removal.

Use screwdriver and hammer to bearing and oil seal if bearing is still stuck in distributor housing. Otherwise you want to use bearing separator to pull of bearing from shaft.

You will have basically never a good bearing nor oil seal after pulling off the shaft from housing. Therefore, be prepared to buy a new 6002 bearing and new inner oil seal when removing shaft from housing. The oil seal has inner diameter of 10mm, outer diameter of 20mm and thickness of 5mm. There is also a spring inside distributor inner oil seal.

[Nordical25]

Latest now it is time to go shopping. Buy if you can a new bearing, oil seal, distributor pin, vacuum advance & ignition coil because it is time to clean remaining parts and to dream of reassembly.

As I mentioned before, there are three models of vacuum advance units. They all fit but you may need to rethink vacuum routing of your car if you swap into different one.

[Nordical25]

You start reassembly by putting brand new inner and outer oil seals into distributor. A small coin like Euro five cents is suitable tool in a bearing press to install oil seal. Remember to install spring towards distributor rotor.

[Nordical25]

Now it is time to check your distributor shaft. See that there are no visible scratches in bearing or seal area. If there are, you may want to sand your distributor shaft before pressing a bearing into shaft. Remember also to lubricate shaft before pressing bearing into shaft in a bearing press. Remember to press bearing from inner edge when assembling it to distributor shaft.

Then press bearing + shaft assembly into distributor housing from bearing outer edges. Otherwise you may end up damaging your new bearing. See that shaft and bearing are pressed into their original positions before moving further in rebuild. Otherwise your rotor may be too high.

[Nordical25]

Now reinstall distributor gear with steel spring pin. See that timing mark in gear is in correct position compared to rotor.

I like to use a hammer and a punch tool for this.