My '85 300SD's starter decided to suddenly die last Christmas Eve when I was doing some last minute shopping! I haven't been able to get to it until now (was away at school)

The connections were bad, so I replaced the terminal box (on the passenger wheelwell) and cleaned all connections to the starter. Still, the solenoid clicks once when I turn the key, and clicks once when I release it. Same result jumping it across the terminal box. I am reasonably sure it is the starter.

Anyway, I had the car towed home and don't have access to a lift. I also don't have access to air tools. I can get the front end up about a foot.

I am having trouble removing the two 10mm hex bolts behind the starter. I sprayed the bolts with PBlaster and they still won't budge. I'm using a wobble and 24" extension (3/8" drive).

Any suggestions? Thanks!

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1985 300SD "The Saudi Prince"

http://www.conservativegentleman.com

You probably need to get both the front and back wheels in the air (with the car secured) and run longer extensions up alongside the transmission and put a long breaker bar on it. It takes a lot of effort to break those bolts free, beyond the gentlemanly amount.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Easiest way I have found is to make around a 2-3cm long 10mm hex stud by cutting a piece off an allen key, then use a long 10mm wrench on it to get good leverage.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Thanks! I'll try both. Do I want to use the 10mm wrench from above or under the car?

__________________
1985 300SD "The Saudi Prince"

http://www.conservativegentleman.com

I think the 10mm wrench would be operated from above. In my case, the 10mm wrench would probably not have worked. It took ever ounce of effort I had on a 2' breaker bar to break the bolt free. Once it breaks free it is easily removed.

Other people have cut holes in the transmission tunnel/firewall to gain access.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

I was thinking about that. How would one patch it up when finished?

__________________
1985 300SD "The Saudi Prince"

http://www.conservativegentleman.com

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Bendix replacement on Bosch Starter - ADVrider


.

__________________
ASE Master Mechanic
asemastermechanic@juno.com

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Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
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Dynamometer.
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Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

https://www.boldegoist.com/

I did the wrench from below usually with the front of the car up on ramps. On the W123 I will sometimes do it from above.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Unless you are the hulk, you won't be able to get the top bolt out by hand from above. Use a jack from below with a 2 x 4 cut to length on the 10 mm wrench/ short allen bit combo to break it free.

__________________
85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Not a chance in hell of breaking them loose with 3/8" drive ratchet and extensions. It's a challenge with 1/2".

The extensions are necessary and an assistant is also necessary to support the contraption while you install a piece of pipe to get additional leverage on the 1/2" ratchet............or use an 18" breaker bar.

Yes.
The 3/8" extensions have too much flex to them and of course the Breaker Bar would not be long enough; you need more leverage.
If possible I would use a Breaker Bar and avoid using a Ratchet Wrench until the Bolts are loose.
It would also be better if you did not use the Wobble type Extension unless you have to.

Harbor Freight sells 12 Volt Impact (that clip onto the Battery or use the Cigar Lighter socket) Wrenches made for changing the Lug Bolts.
While it is made for changing Wheels I have found it is almost as good as a Pneumatic Impact Wrench.
I managed to remove the Crank Shaft Bolt which is torqued to over 200 ftlbs with one and it will easily snatch off and tighten an Alternator Pulley Bolt.
It speeds up Tire Rotation too.

They also have AC type Impact Wrenches that Plug in to the Wall Socket in your Home but I have never used one.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel

and detach steering damper at one point and swing out of the way, much easier access -

Lot easier w/ the motor out ;0).

In general w/ tight nuts/bolts/cap screws:
Whack the head from the side w/ a 2lb hammer & a drift a couple times.
Had some success w/ 50/50 ATF & acetone as a penetrant. Makes you dizzy on a hot day tho.
The hot wrench has been my friend in loosening up stuck suspension parts.
Clean out the recess of the head to get good & full engagement of the (well hardened) hex key. Seat w/ hammer if you can.
You can notice the feeling of a head that is about to round out or break off, usually after a fit of gusto has left you looking at a head broken off in your socket and some bloody knuckles.

Having a car come off a stand, or a stand become unlatched, will change your thinking forever (my case) or end it. If you are under there with a breaker bar, be mindful that a car on stands is much easier to topple w/ a lateral force than lift with a vertical force. Orient your breaker bar accordingly. Fortunately the floor helps you in this regard.

__________________
CC: NSA

All things are burning, know this and be released.

82 Benz 240 D, Kuan Yin
12 Ford Escape 4wd

You're four times

It's hard to

more likely to

concentrate on

have an accident

two things

when you're on

at the same time.

a cell phone.

www.kiva.org It's not like there's anything wrong with feeling good, is there?

So how did this turn out?

I second PawoSD about the allen key. I used my 10mm allen socket and drove the key from the socket. Used a 10mm ratchet wrench from above. Mine weren't too tight. But if they were I'd just get a long 10mm box and heat and bend the wrench as necessary to clear the firewall. Put a pipe on it for extra torque.

This solution is strongly discouraged for the following reasons:

1) Driving the allen key with a 12 point box wrench seriously risks rounding the key. Most do not have six point box wrenches.

2) Maintaining the allen key in a perfectly straight attitude into the fastener is nearly impossible from above. There is no capability of providing any forward force on the allen key unless another person is utilized. If the allen key does not remain straight, the risk of rounding the key is high.


The preferred solution (minimizing the risk of failure) is to utilize a 1/2" drive hex bit with about 30" of extension, a 1/2" universal, and a breaker bar with added pipe from below. Forward force into the fastener can be maintained.

You only get one chance at this attempt. Failure is brutal.