Probably because the cheap re-builders use cheapo grease. The Bosch ones seem to fire off just fine in the sub-arctic temps....

__________________
-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)

Well, if you must replace it go with a Bosch German one. I know this is money and you just paid off your credit cards, but this is one part worth the debt and paying it off ASAP.

I think it is worth it to spend a little time in the warm store and let the test it.
At least you will not be wasting your time installing a dead Starter.
Also if you know it tested OK in the store and it does not work on your car it could also indicate that you have another Electrical problem.
In short having the Starter tested gives you more information to work with as does having the old Starter tested.

__________________
84 300D, 82 Volvo 244Gl Diesel

In that pic that I posted there is the word Contacts and 2 arrows pointing to the contacts.

After years of use those contact areas become burned and oxidized and create a lot of resistance or one contact gets burned lower than the other and the disc/plate inside will not make good contact.
This can cause the starter to work intermittently.

Unfortunately a complete new Solenoid cost almost as much as a rebuilt starter to much to trouble shoot by replacing parts. However, if the Solenoid can be removed and the Solenoid end cap removed you can look inside and see the condition of those contacts.

They can often be cleaned up or filed down (one Member said he rotates the contact bolts to an area where there is still good metal).
You can also take a peek at the Brushes in the Starter and see if there is very much left of them.
I believe they sell new brushes for Bosch starters at the Chain Parts places.

__________________
84 300D, 82 Volvo 244Gl Diesel

I bought a Bosch Reman starter for my VW at a local parts house. Installed it and discovered it was no good. I had bench run it before the install and it spun fine!
Turns out the end cap that is bolted to the shaft end had been damaged and interfered with proper operation when under load.
A pita to remove, install, remove, install.
Look your purchase over carefully and don't trust a bench test.

__________________
1981 240D 143k 4 spd manual -SOLD

2004 VW Jetta TDI 5 speed 300k -still driven daily

My starter worked fine for a few days, but I stopped at the post office on the way home today and when I came back the starter would not work.

I put the rubber end of a long hammer on the starter and then hit a sledge hammer against the long hammer. Repeated tries did not work.

So, I got the car rolling with the transmission in neutral and the key in number 2 position. I rolled down a hill and then put the transmission in S toward the bottom of the hill. It was not enough to build up pressure in the transmission fluid to turn the engine.

I let the car roll into another parking lot and then tried tapping the starter again. The starter is not very accessible and hard to reach. I tried a small hammer and reached down and tapped he solenoid toward the front. I turned the ignition switch and the car started! Now I think I know where to hit the starter to get it to work.

I suppose I'll save my money for a good one. Maybe my tax return will help. I'd like to install a used starter to save money, but I'd hate to install it and discover it doesn't spin as fast as it needs to. And on the W116 body style the starters are a pain to swap out.

I went out and tried to start the car tonight to see if it would start again. Nothing. I hit the solenoid a few times and it still wouldn't work. I am just glad the car is home and I won't be trusting the starter anymore. I'll just borrow my friend's fintail Mercedes to get to work tomorrow.

Now that I think of it, the last time I bought a new starter was through a parts store chain. It was for a 1967 International Travelall. I went through 5 new starters before I got one that worked.

All in all you'll only spend like an extra $65 or so getting a good german one from Fastlane. Its not worth the risk and hastle to go cheapo.

__________________
-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)

I know it isn't like most people's experience on here, but I replaced mine on the 240D with a turbo model starter from O'reilly's for around 80 bucks. It has a lifetime warranty, so if it ever breaks I take it back and get another. I can't speak for replacement difficulty, on the 240 it's pretty easy though.

I may have just gotten lucky, who knows. Mine seems to work fine.

__________________
'79 240D 4 speed manual 105k miles

Another one of my CSK starters went out AGAIN! Today all it would do is spin and not turn the ring gear. I have gone through too many starters to keep this up. I installed an old, dirty Bosch rebuild and after visiting two stores and finally talking to the right person I got a refund. No more cheap starters! Of course, there were the clowns who said, "you can't return it, it's used" and "we're not going to be able to resell it like that"--no kidding, it doesn't work; that's why I want to return it!