The problem:
(in a 1986.5 MA70 toyota supra 3.0 turbo auto, ex-japan.)
For the last few weeks, my car had been hard to start - mainly in the mornings - sometimes just dead - then hard starting. I suspected the battery was getting low over night, but it seemed OK otherwise.
On friday last, after work, the car just would not start - no cranking, I popped the hood, and noted that the solenoid on the started was striking (good solid 'click' when I turned the key) but no cranking - It was the starter I decided - I kept on trying, and it caught after around 10 minutes of trying - I parked it somewhere easy to work on and planned to fix in the next morning.
NOTE: I work on cars as a hobby - I am a computer systems analyst (and general dogs-body..) - my brother in a motor-cycle mechanic, and I live on a farm - so I have a 'good' mechanical background, but nothing special - I have done 1 motor swap between 2 1970's chrysler valiants (265 hemi's - great cars..) but these are easy!
Also: I drive in New Zealand, we drive on the correct side of the road (smile...) and therefore have right hand drive cars - these are set out the way toyota designed the cars (japan is right hand drive) and are therefore a bit easier to work on that the US versions..
Anyway.
The solution:
I am a cheap bastard, so I was going to fix this my self!
On saturday morning, I got my brothers tools, and started work:
1 - I pulled of the positive terminal on the battery - essential as the started motor has an un-insulated high current lead going to this, and this would be a *bad thing* to short out. It is possible to take of just the starter motor wire at the terminal, but make sure you get the right one (this stops your clock, computer, CD, etc from forgetting...)
2 - I removed the clips holding the thick started motor power cable so that it could move free when I removed the starter. there were 2 plastic clips along the run - they were easy to remove. I also removed the control wire from the started motor (the thin wire..) - It clips on underneath the starter, and is a retained clip - so you need to press the clip to remove it - not too hard but fiddly.
this took around 10 minutes to here..
3 - remove the 2 retaining bolts. These are hard to get at, even in the right hand drive - probably harder in US models. I seem to remember that they were 14mm, and were proper bolt-nut combinations, with the nut on the 'front' (ie: towards the front of the car) - I put a ring-spanner on the bolt head, and a short handled socket wrench (you know, the type that click...) on the nuts and took them off - it was tight, and the bottom bolt had a clip on it to retain a set of wires running near it - but it was not too hard - there were no washers to lose.
this took around 30 minutes to here..
4 - with the 2 bolts out, the starter was easy to 'extract' - I took it inside to 'fix' (lots of news-paper, etc..)
It dis-assembled easy - the 2 long external bolts hold the engine to the gearbox/solenoid, remove them and the 2 come apart easy (this turned out to be un-nescessary - but I may as well cover everything..). There is a cable from one to the other, lift on the covering boot on the gear box end and remove the bolt to remove this wire (10mm, from memory..)
The motor can be dis-assembled (to get at the bushes, etc) by removing the 2 screws in the back-end of it, and pulliong it apart carefully - the center rotor pulls straight out (I cleaned the contact points on this lightly with a bit of sand-paper, etc were looking OK) - the body splits in 2 - watch out for the bush retaining plate - it is wired to the center (plastic) part of the motor, and if you break these wires you will need a new motor!. The bushed where good - I just cleaned everything (lots of dust, etc...) I re-assembled the motor by putting the rotor into the middle body piece, and getting the bushings onto the center body (quite easy), the placing the end-body piece on and replacing the 2 screws to hold it - In general I was very impressed with the build - I doubt the motor will ever need replacing-fixing.
this took around 40 minutes to here..
I then attacked the gear/solenoid box. There was an obvious cover on the non-gear end, held by 3 bolt-head phillips screws - they came out easy - there is a rubber gasket around this plate - so remove it carefully. This exposed the contact points for the solenoid (ie: that supplies power to the motor) and the root of my (and I suspect most others) problems. There is a centeral moving piece - which pulls straight out (there is a loose spring down it's center - but it has no tension, and will not pop out..) - this is the moving piece of the solenoid and does not look like it will ever wear out. - pulling it out revealed the contact points - these lead out to the 2 large copper power connecting bolts on the outside. these were *real bad* - worn down about 2/3 of their 2mm thickness - and uneven - these were just not contacting well..
I sanded off the copper contact ring from the central 'bit' to make it contact better, and called toyota about replacement 'solenoid contact bits' - they had generic 'japanese reduced-gear starter motor' bits, so I decided to go get them.
To remove the old bits you must remove the big copper power-bolts - this is easy with a 14mm ring spanner - just remove the outside retaining nut and ease them out - remember which ones went where, and the order of the washers - REMEMBER - when you re-assemble these the plastic insulating washers *must* go in that insulates these bolts from the main body (you will get a big bad blowup if they are not..) - one of the 2 bolts has a contact washer leading to a wire for the solenoid - carefull not to break it.
I took the old copper L-shaped contacts to a toyota dealer and got replacements (they had 2 sizes, so take yours along..) - the replacements were the correct size - but a slightly bigger contact area - this was not a problem - the cost was $9 NZ (around $6 US)!
Re-assembly was the reverse of disassembly - just make sure you get the insolators in the right place, and clean everythiong will before you start - the icky (tm) black gunk in this area is actually oxadised copper dust (from the contacts) and should be cleaned out well.
NOTE: if you check for continuity (uting am ohm-meter, etc) you will find that the bolt with the wire attached seems to be grounded to the body - it is not - the solenoid coil is grounded at the other end (well, half way along) inside the solenoid body..
Check the new contacts are sitting flat, and that the contact bolts are firm - replace the rubber gasket (it only keep dirt out..), cover and 3 screws.
Time to here (ignoring trip to toyota) 50 minutes.
I then cleaned up the outside of both body-parts, and re-assembled the 2 together (with the 2 long bolts) and re-attached the connecting wire between the 2.
The started motor was now together.
I placed in on the car and tested it before I installed it properly, I connected the main power wire o both the starter motor and the battery (being real carefull about shorts..) made sure the started motor body was earther to the motor (help it agains bare metal) and connected a wire from the battery + to the small control terminal - the starter motor cranked (carefull - it has some serious starting torque..)
I removed the batter connection again (always do this!) but left the big cable attached to the started motor - installed the small conntrol wire, and maneuvered the started into its correct place (not too hard...) - note: make sure you get it the right way up, and watch out for the connection to the knock sensor - which is on the block in this area. also: make sure you get the starter the right way up - it seems like it wil go either way - but it will not: the wires to towards the bottom (road..).
I placed the 2 retaining bolts back in, and did them up the same as I removed them - this was not easy - but just takes patience - I used a ring-spanner on the bolt head to hold it, and a socket wrench on the nuts to do them up - I also put the cable-holding washer back on the lower bolt. remember - do these nuts up quite tight - they hold the starter while it turns over the motor: quite a stress..
I checked everything for tightness, replaced the battery connection for the starter motor, and cleaned up the engine bay (make sure I have removed all tools, etc..)
We are now around 1.5 hours into the work (ignoring the toyota trip..)
I got into the car and turned the key - but nothing! I panicked a bit untill I noticed that I was not in park! felt stupid - put the car in park, and it started better that ever before - I have had no trouble since!
I suspect from the build, that 90% of all starter motor failures will be in this contact area - if your starter motor makes a nice loud 'click' but does not turn over (even if this is intermitent) I strongly suspect you just need the 2 $6US contacts replaced - a mechanic will probably charge you hundreds and a reconditioned starter (which probably is just cleaned and has these 2 contacts replaced..).
the moral of the story: Learn to work on your car, it is fun, and it pays well ;)
PS: I have had another starting problem a lot while ago: the car goes just dead - nothing - the neutral/park switch was out of adjustment and needed adjusting - it is under the car on the side of the auto (for an auto..) and the haynes manual covers adjusting it (quite easy if you have a jack..) (REMEMBER: always use jack stands (or tree stumps, on my farm...) if you are working onder a car!.) - the 'auto gear selected' thing on my dash (digital dash: shows P, R, N, D, 2, 1) would sometimes read nothing (it: no display) - this was the same problem - auto position sensor switch - same as start switch - needed alignment..)
anyway - I give no guarantees - but this is an easy fix which I think some people out there may appreciate - but if you kill something - don't blame me! ;)
Stuart.