Bill Gregory

Having just replaced the starter, here are some things to be aware of. This 993 article does a good job, with included pictures, of covering the procedure, so I won’t repeat it all here.

Replacement starter: Bosch SR0451N, new not rebuilt (so no core return), $211 from Rock Auto. For comparison, new factory 996.604.107.02 (supersedes 964.604.104.00)
discounted around $1K (list $1,798) or factory rebuilt discounted around $600-$700. Bosch includes 2 years of free towing and battery jumps with the starter motor purchase.

FYI, the factory replacement procedure is:

• Disconnect both battery cables at the battery
• Disconnect both axles at the differential
• Remove both sides heater hose
• Remove both splash guard holders
• Remove clutch slave cylinder
• Disconnect starter electrical leads
• Remove upper starter mounting nut from driver side
• Remove lower starter mounting nut from passenger side
• Disconnect ground strap on lower starter stud

As shown in the 993 article, you can do the replacement all from the passenger side, so you don’t need to touch the clutch slave cylinder or do anything on the drivers side.

Main thing is to get as much out of the way as possible, as there is precious little room to fit a socket wrench, when removing the upper starter nut. Use a 10mm allen hex socket
for both mounting nuts. For mine, the lower nut was rusted to the stud, so both came out together, which is OK. On top, only the nut came off, which is good, as removal with the
stud would have been challenging, given space to work in.

Getting the 10mm hex socket on the upper starter nut can be challenging, as you can’t see anything. I found it easiest to let the socket/extension roll to the right to where I could see
it between the solenoid and starter, then, with the tip of the socket as far forward on the starter as possible, move the tip around the starter to the left until it hits the upper nut.

While the torque spec on the two mounting nuts is 40nm/30ft lbs, the upper nut didn’t want to budge. Ended up using a 1/2” metal pipe angled in from outside the wheel well to the
handle of the socket wrench, and a hand sledge, to convince it to loosen. The replacement starter is roughly an inch shorter, which provides for an easier install, and allows room to
torque the upper nut.

Six axle nuts need an 8mm allen hex socket, with torque 42nm/31 ft lbs.

Mark in Baltimore

@Bill Gregory, it's good to see you back here! Been a long time, but I have appreciated all of your past posts and have read many of them over the years.

Hope you've been well.

Ken D

+1! Thanks for posting, Bill.

Bill Gregory

Thanks Mark!

AOW162435

Bill,
Nice writeup. I've yet to mess with a 964/993 starter replacement, but am curious - would unbolting the engine carrier and lowering the engine a few inches afford enough room to make a difference?



Andreas

John McM

It does help. It’s a real bear getting to the top nut and then managing to get enough movement on the wrench to work the ratchet.

Bill Gregory

Even an inch or two of additional clearance would be a major help! I thought about lowering the engine that way, but as a second option if the first path didn't work. Although I used to lower my 911SC engine that way when some extra room was needed, I've never done it on the 964, and didn't know if it would drop without any complications, as with the 911SC. Also, while using the bottom of the engine casing to raise the rear end to get it on jacks, since the factory doesn't recommend that as a 964 jacking location, I like to minimize that as a jacking point.