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How to replace worn Starter Motor...

102K views 68 replies 18 participants last post by  Kimmie11345 
#1 ·
OK First off I have to say this was the hardest starter job I have ever done, perhaps one of the harder jobs ever. It officially was done in about 6 hours over 2 days where a normal starter job would take me 15-30 minutes. I've replaced clutches on FWD vehicles faster then it took me to remove the two blots off the starter and the three wires then to replace the worm unit. This job is not for the light duty DIYer nor the impatient!

Well the conditions for this job were hovering around 15' F windy and bitter dry. The next recommendation is that if you have to do this job (God bless your soul) you do it in a warm environment. My starter was erratic when it wanted to start. I had a hammer with me and would tap the starter to get it to turn but it was getting worse fast. I was hopping to make the little bugger last till spring... It finally seized to function and I was forced to do my starter in these brutal conditions (my garage is and was currently occupied by my slumbering Miata).

NOW TOOLS!
First off your going to need a 10mm, 13mm, 15mm, 17mm and 19mm sockets with 17mm wrench to remove all the bolts that hold the things in your way together. You will also need a flashlight, flat head screw driver, ratchet, a couple of extensions, a crowbar, a bottle jack (to move the tranny up and down) and this device that I created on the second day to get to the exceptionally hard starter bolts.

This thing made the job way easier and probably shaved 3 hours off my project time. It's made up of a ratchet, 4 wobble tip extensions, a u-joint extension and a small thin walled 17mm socket. It can bend up to 90 degrees.

First step is to jack the car up... Your going to have to learn to be a contortionist for this job and you need to be able to attack at every limited angle that you can. Make sure you use jack stands!


Second step is to remove the Battery! Very Important! When you remove the battery make sure to clean up the terminals and the battery posts! This requires a 13mm ratchet for removal.


Now look into the void that is the dwelling of the Starter... Want to shoot your self yet? You will in a few hours.


Next step is to accesses the tranny cross member and remove the two 13mm bolts that hold the tranny in place. Your going to have to have to swing the tranny up and down with the bottle jack in order to reach certain bolts. Make sure you disconnect the exhaust bolts too! I'm pretty sure they are 13mm as well.


Now we have to gain access to the starter but we are going to have to remove a few things things to be able to do so. (personal note: it took me the whole first day to remove all these things). Well first your going to have to remove The air box. Your going to need a 10mm socket to do this. After removing the air box your going to have to remove the MAF, the intake plenum and all the vac lines attached. You will only need a flat head screwdriver to unfasten all of the hose clamps. I left the MAF attached to the top side of the air box for convenience. Next step is to remove the throttle body. You will need a 10mm socket with wobble bar extensions to remove the four throttle body bolts and the flat head screwdriver to remove the hose clamps. There is 2 vacuum lines one small one that goes to the Carbon canister and one big one that goes to the valve cover. There is also 2 coolant lines that hook into the throttle body to help heat the intake air for better fuel atomization. (You can bypass these lines with a brass fitting I've always noticed a slight increase in power after doing this mod on several cars). Don't forget to remove the throttle cable and the clip for the TPS. Now you can remove the TB. I also removed the vacuum line for the brake booster, The main fuel line and a clip holding a large wiring harness. This is what it looks like after your done.


Next step is to remove the Heater core coolant lines... One of the easier steps..


Now remove a bracket that holds two wire clips to the motor directly behind the starter motor. You have to remove the right clip before you can access the 19mm bolt. Your going to have to use the tool I created to loosen that bolt.


NOW WE CAN START WITH THE STARTER!!!

First remove the three wires from behind the starter solenoid, There is a thick Black one, a thick Red one and a thin Black one with a yellow stripe. The thin one just slides out off the clip, the other two need to be removed with a 10mm socket DON'T LOSE THE BOLT!


Now have the tranny jacked up all the way with the bottle jack. Now you can gain access to the TOP starter bolt on the tranny side. Slide the open end side of a 17mm wrench onto the starter bolt then secure it. Now snake the tool I created onto the 17mm nut on the starter side. It may take some time to get the tools into place but you should be able to loosen the nut and bolt. Leave the bolt in place DO NOT REMOVE IT FROM THE TRANNY!!! You will never get it back in if it falls out. I wedged the crowbar to hold in place when I reinstalled.


Now drop the tranny out slowly and let it hang, you now have enough room to slide a 17mm wrench on the BOTTOM starter bolt. Now contort your self into a painful position and snake the tool I made onto the the starter nut. The positive side of this nut and bolt removal is that it comes out way easier but your in so much more pain when you do it... Once again leave the bolt in.

Now slide the Starter out!
Here is the old starter next to the Bosch re-manufactured one.


To reinstall, slide the new lighter and less awkward starter onto the starter bolts. Be careful not to lose the starter bolts hand tighten the nuts till you need the ratchet and then reinstall everything backwards to this write up.

Remember to tighten all the hoses and replace any broken vacuum lines! I forgot to tighten a coolant line and coolant went spewing every where! Also had a stalling problem and thanks to Whiteshark I double checked my vacuum lines and found some nasty leaks. Replaced the damaged vacuum lines and tighten all the clips. Now the car STARTS and runs.

Hope this was helpful!
-Jedz
 
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#3 ·
Great write up a pics , Well done, sounds like a total sod to do, I presume it was easier to put back the new one as its alot smaller?
 
#4 ·
Thanks Guys! and thank you again WhiteShark! My car wouldn't be running without your advice (found in another thread)

The new Starter was WAY easier to work with... Putting it back together seemed to be easier then ripping it apart... The old Starter was PITA to work around for the motor part was so big you couldn't reach around it without that tool I made.
 
#6 ·
you don't take a starter out from the top of engine...you take it from underneath. Jack the car up and take it out and put a new one in. Do think BMW would intentionally design something that difficult to replace? If you are adverse to laying underneath a jacked up car that's another thing. But you replace the starter from underneath car generally. You can do it from above but it's 10 times more work...good luck
 
#7 ·
Silver, if you read the write up and looked at the pics you will see that the car was well lifted off the ground and on Jack stands. BELIEVE ME I was on that ground and under the car for well over 3 hours to get some of those bolts out. I also was under the car to to move the transmission up and down with the bottle jack to loosen and access stubborn nuts and bolts. I wasn't able to access some of the bolts on the top end until I removed some of the induction system. I can't imagine tackling this job in a timely fashion strictly from underneath the car... In fact I don't think there is anything timely or easy about this job in general...

I don't think any car manufacturer intentionally makes things difficult. But for the record I have replaced starters on these car makes:
Mazda, Subaru, Toyota, Nissan, Crystler, GMC, Chevy, Pontiac, Ford, Honda, Acura and now BMW.

I'm saying the BMW starter was the hardest I've ever replaced out of all these car manufacturers... Easiest hands down was Subaru I can and still have a starter replaced in less then 10 minutes God bless their rally inspired easy drop boxer engine and AWD transmission setup!

Crispy, I hope no one ever has to do this job and if they do I hope my write up will be a beacon in some respect. I looked around before hand to see if anyone posted anything about this job and all I could find was a Pelican tech article stating that the intake manifold had to come off in order to take the starter out or take the transmission out, the site rated the job a 6 out of 10 in difficulty. Here is the link to the Pelican tech article. At least my way you don't have to rip the intake manifold off or take the transmission out...
Thanks Guys
Jedz
 
#8 ·
6/10 for difficulty... those ratings are usally pretty bang on. I am just about to do a LSD diff swap and that is only rated 4/10. Just waiting for a warmer day cause I'll I have is a car port to keep the snow/rain off me while I work.

Props to you for the starter replace job!
 
#9 ·
Its hard job,bad noth that hard.As i can see,you did not have lot of space to do that underneath.Its much easier if you do that in some garage.Here,mechanical guys do that for 15 - 20€.truth is that I newer do that so far,and hoppe I newer have to,so maibe I´m wrong.Last summer I remove the heater fan from the cabine,and thats real gymnastic(I am big guy)...
 
#10 ·
yes, i just replaced the heater/blower motor on my 88 325ic this past fall...shaft bearings were totally shot...rumbling like 40 going north (as they say around here)....found a beauty at a junk yard for $15 with cages intact....the bitch was putting it in my car properly. It was easy to remove the old one from my car and the one from the junked car. The trick was to replace the junkyard good fan into the not junkyard mycar without wrecking it (the blower). That was a trick...after much finagaling I got it in and 'strapped down' (as if it were an astonaut) and tested it out...would only work on high speed (4)...turns out somehow I had damaged the resistor and had to drive back out to get the resistor for the multi-speed fan out of the same car I just pulled the fan out of...they prised me for $4 for the used resistor....can't complain...but it is a bitch to put the new blower cage in there on an E30 without avoiding pain....I hear that...but this is why they are BMW's...and why I put up with them....for every proclivity they offer 5 fold admirable characteristics.
 
#11 ·
OK, I just did this job sort of following the above post. You do not need to remove the throttle body, the heater hoses, any vacuum lines, or the tranny support. It did not allow any better access to move the tranny up or down, you can't really get to the tops of the bolts regardless, but they snug up without having a wrench on them if you jam them with something between the firewall. You also don't need any fancy super long extensions. I did it with just a 6" and a 12". The 6" for the nut closest to the block and the 12" for the nut closer to the fender. I was not able to source a new, ie. smaller and lighter, starter, but the original sized one went on with no real problem. Very important to watch the bolts as you slide the new starter into place, you do not want either of them to come out of the tranny housing as there is no easy way to get them back in the holes. I was dreading this project from what I read here, but it was not that bad. So, if your starter is a squealer, just do it, no biggy.
 
#12 ·
and I have looked at the starter motor on my 1988 325 and hope to god I never have to replace it...it looks like exactly what you say and displayed.
I know I will not look forward to that job....I am hoping that the starter will last until the head (180K original) needs work and then I'll do it all at once....I am hoping it will all sequence properly while recognizing it's basically luck.
 
#14 ·
JUst to aid you guys

The top bolt on my 1988 BMW starter had a nut on the back with no way to reach it. We took some clear fishing ling and tied it to the end of the threads on the bolt. Then threaded the line through the hole and had someone wiglle the line while I painfully jammed my fingers in there to line it up. The bolt jiggled up and slid into place allowing me to have someone hold a long screwdriver on the bolt so the nut could be threaded onto the bolt then tightened. Voila! A hairy job done easy. Hope this helps. WORST STARTER JOB EVER!
 
#15 ·
help

I'm currently trying to just tighten the top bolt and that's it. I'm having a hell of a time just trying to do that. i can't seem to get a wrench or anything on that back bolt :headsmash. I even tried wedging a screwdriver back there so it wouldn't move. Still suggest going under the car? Maybe i need somebody with really tiny hands.
 
#18 ·
help again

I ended up replacing the starter. I think the old one was dead. I just bought the car this weekend. I was told the starter needed to be tightened down before you could start it with a key. To drive it, it had to be push started. It drove great. So i put the starter in and now it wont start. I haven't push started it yet. I hooked it up wrong the first time, but the directions said that was fine, it wont hurt it. When i did this it sounded like the motor was just spinning the flywheel, no abnormal sounds. I hooked it up to what seems to be the right way. It doesn't make a grinding, banging, or squealing sound. It's more of a hard start sound, idk. Any ideas? I don't think its the flywheel teeth because it seemed to have spun just fine in the error trial.It's a brand new starter. btw, once i figured out good tactics to get at the starter, it went smoothly. If i had to do this again it probably wouldn't take more then 20 mins to complete. You don't have to remove ANYTHING or need special tools.
 
#19 ·
Re:

After thinking about what the noise is, it kinda sounds like the gear is trying to engage the flywheel going the wrong direction. The tip is just spinning/grinding against the flywheel trying to go in...i think. I hooked it up the same way as i took the old one off though. Kinda leads me to believe that the original starter was hooked up wrong. This is why i think one of the bolts was loose and one of the ears of the starter broke clean off. May seem dumb but can somebody reassure me that i wired it right or does somebody have a close up of how the starter is suppose to be hooked up? if looking at the starter from the drivers side of the engine bay, the big black and the big red are both on the connection closest to you. There's a small black wire that was wrapped with the red cable and this is goes on the relay terminal which is the bottom connection? There's another wire that is shorter and seems to come directly from the engine alone. i connected this one to the top connection(Start terminal?) Ill take a picture if it helps to visualize it.
 
#20 ·
Tightening bolts!

Dude you are making it too hard. Just grab the front of the long bolt with a pair of small LIGHTLY set vice grips so you dont harm the threads and tighten the nut till it snugs tight and you can then crank it tight enough to hold it permanently. If you are worried about it being loose or working loose slide on a lockwasher behind the nut. Easy as pie. You can use a convoluted small socket and extensions and swivels but why? Make life easy. Do it from the front.
 
#21 ·
MTO: My ear was broke too! The starter has grounding problems! Hook the line from the battery and the extra from the black loom to the outside terminal large. Connect BOTH wires that are small to the BOTTOM connector. Nothing to the top or your power windows and ac fan won't work. Then take a 12 gauge black stranded wire and put a yellow o ring connector on one end. Loosen one of the long skinny bolts on the end of the starter motor and slip it on and retighten. Then route the wire up to the main ground connection by the battery where the battery grounds, put on another o ring terminal and place on ground with rest. It will start like a top every time and no more click click crap. I didn't NEED a new starter and you didn't either except for the broken ear. IT is a Ground Problem. I spent 134.00 to learn this hard lesson!
 
#22 ·
Well that would explain why both thick cables were on the positive terminal when i got the car, but somebody didn't add the extra ground wire. So in your setup the engine gets the start signal from the relay terminal? The top wire which is suppose to be on the starter terminal is just short of reaching the lower relay terminal on mine, plus i think its too small to fit on? How does having the starter terminal on the relay help make the ac fan and windows work? I didn't check yet but ill make sure they both work tomorrow. I gotta rewire my positive cable all the way back to the battery. I smoked and fried it. :mad People really should pay attention to what color cables they put in.
 
#23 ·
MTO: I just hooked both my wires together to the bottom terminal. It just works better. You can put the smaller one on the top terminal but it makes your windows slow and gets hot.Best to splice them both together and hook to the bottom terminal and it will work perfect. I tried it every way and it works best. Run a new 6 or 8 stranded red straight to the battery and to the outside large terminal and then run the ground just as I said. It will start every time no sweat. I believe the top terminal was supposed to kick out the windows and blower fan to start but it just messes up so hook both to bottom.
 
#26 ·
Hey, not trying to hijack your thread or anything, but i believe i have a similar problem as you.
I think i understand what you are saying about the ground wiring, Kenne, but if you get a picture of that, i would like to see it.
Obviously help mto first, but i think this may solve my problem as i have a known-working starter.
Thanks!
 
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