Starter motor rebuild

Yesterday I started to rebuild the starter motor of the Volvo 122S. When I bought the Volvo the Bosch starter motor was in bits. First I cleaned everything and checked if all parts were in the box...

Bosch starter motor Volvo 122S in bits

Hmm, there wasn't an exploded view in the Haynes manual.  But today I found an exploded view in the Volvo/Bosch parts catalogue. Ok, lets put this thing back together. After some trial and error I found a method to jam the springs to make it easier placing back the brushes in their holders. The brushes on the brush retainer plate can be hold in place with some wire.

Jammed spring of brake plate Bosch starter motor

Exploded view of Bosch starter motor 0 001 311 001 Volvo 122S

Cleaned Stator Bosch starter motor

Bosch starter motor 0 001 311 001  ready for the test

Testing Bosch starter motor 0 001 311 001

After rebuilding the original starter motor I tested it on the workbench. It worked but there was a problem with the solenoid. Once the bendix was out it wound't withdraw. 

So I took apart the spare Volvo 240 starter motor I got from Chris Povey, the Volvo specialist in Adelaide, to have a closer look. It wasn't exactly the same starter motor but close enough and even better, it fits the 122S engine. Also Bosch and the same size as the original. The brush retainer plate was different, there was no possibility to jam the springs, so I put some wire around the two brushes on the retainer plate , put it on the shaft and then grabbed the spring with a plier so I could fit the brush in the holder. 

There were also a couple of washers missing and one of the through running bolts was broken. I used the parts of the old Starter motor to fix this one.

 Bosch starter motor 0 001 311 146 from a Volvo 240

Fitting brush in brush holder Bosch starter motor 

Bearing shield in place and putting back the washers and circlip

Bosch starter motor 0 001 311 146

with 0 001 311 001 parts ready for the test

Wiring diagram for testing starter motor

Testing the Starter motor. 

All good :)

  

Replacing the B20B Valve seats

Last week the outlet valve seats were replaced by new hardened ones. If you want to use lead free petrol or LPG you need harder valve seats than the original  valve seats who are directly cut into the edge of the valve port of the cast-iron Volvo B20B cylinder head.

And while the engine was still disassembled I brought the cylinder head to Chris Milton Engines
Sam took some pictures of the whole process.

Cylinder head Volvo B20B

Cylinder head and new exhaust valve seat

Removing the old valve seat

New uncut valve seat in place

Cutting valve seat 

Cutting valve seat

Valve seat cutted

Refined shape of outlet port with new hard valve seat

Ready

Sam also did a vacuum test on the inlet valves; all good. Normally there´s no need to replace the inlet valves because they get less hot then the outlet valves.

Rusty B20B engine

After being for more than 12 years dismantled most engine parts of the B20B were quite rusty.
I tried cleaning up the cylinder head, piston rods and some other parts with steel wool.
But it just wasn't going to get me too far.
After removing the grease and dirt it was obvious that the head and block need a light face and the bores a light hone. Another thing to do while the engine was still in parts was balancing the flywheel, crankshaft and piston rods.

After some surfing on the Internet I found Chris Milton Engine Developments just around the corner...
Specialised in high performance engines and engine developments and ... they have engine baths !

After bathing the parts the crankshaft journals needed a grind to get rid of pitted surface. Because of the grinding I couldn't use the original new bearings that came with the car :(
The chemicals in the bath are very aggressive so it's also necessary to replace the camshaft bearings after bathing the block.

The results are shocking good :

Volvo B20B head before cleaning

Volvo B20B head before cleaning

Volvo B20B head after bathing and a light face

Yes, it's the same head

Crankshaft Volvo B20B before cleaning and grinding

Crankshaft Volvo B20B after cleaning, balancing and grinding

Rocker shaft Volvo B20B before bathing and cleaning

The rocker shaft took a bath, after that I took it apart, cleaned it with steel wool and soaked it in oil.

Flywheel before balancing

Flywheel machine stepped and balanced

see drilled holes between the 2 white lines

Friday I can pick up the block with the new cam shaft bearings and the cleaned inlet- outlet manifold, Pics of the results will follow. So it's time to find me some long bolts to mount the engine on the engine stand and start reassembling the B20B.

But... before reassembling the engine needs a good paint, red, Volvo red.

Volvo Amazon 122S 1969

Restoration Volvo 122S  1969.

I found the car in April 2012. It has been sitting on a veranda in the Barossa Valley for over 3 years. Before that the Volvo was in a shed for over 9 years, without the engine. The B20B engine is in parts so it needs assembly and probably some new parts. The previous owner started rebuilding the engine 12 years ago, so the engine came with a lot of new parts. 

At the moment I'm stripping the car so it can be soda blasted.

Empty engine bay..

Sandy likes the Volvo too :)