1994 530i Water Pump Replacement (Broken 4" Bolt inside Engine) JUST NOT MY DAY!!

[Green Bimmer]

Joe in Orlando
1994 530i

broken bolt inside engine when installing water pump. Can someone please tell me how can I get the broken bolt out of the engine myself? The bolt is normally 4 inches long but 1/2 inch is stuck inside the engine.

[yaofeng]

Looking at the picture of my v8 when it was still in the car, I think with the radiator removed, you'll have enough space to work with. You need enough space for a drill. The water pump needs to be removed of course. So is the throttle body. You may want to also remove the flex damper.

Go to Home Depot to get yourself a set of Cobalt drill bits. The trade name is Blue Mol. These drill bits go through steel like butter. But you need to be careful because the aluminum block is actually softer than the stuck bolt. The Cobalt bits are also quite brittle being so hard.

Use a center punch (the smallest size finished nail punch) to punch an indentation right in the center of the broken shank so you can start your first drill bit centered. Start with the smallest drill bit to drill into the shank. Don't go deeper than the broken shank. You don't want to drill into the block. Increase the drill bit size one at a time until you reach the maximum bit size required by the proper size bolt extractor. Then use the bolt extractor to get the shank out.

http://i21.photobucket.com/albums/b274/yaofengchen/BMW_95_540/DSC_3117-1.jpg

[yaofeng]

Whether to remove the hood is up to you. Considering the criticality of the task, I'd remove it so you can work directly in front of the engine.

[632 Regal]

try to find a set of reverse drill bits, then do like yaofang says, sometimes the reverse bits will unscrew the part stuck in there.


Joe in Orlando
1994 530i

broken bolt inside engine when installing water pump. Can someone please tell me how can I get the broken bolt out of the engine myself? The bolt is normally 4 inches long but 1/2 inch is stuck inside the engine.

[Green Bimmer]

Looking at the picture of my v8 when it was still in the car, I think with the radiator removed, you'll have enough space to work with. You need enough space for a drill. The water pump needs to be removed of course. So is the throttle body. You may want to also remove the flex damper.

Go to Home Depot to get yourself a set of Cobalt drill bits. The trade name is Blue Mol. These drill bits go through steel like butter. But you need to be careful because the aluminum block is actually softer than the stuck bolt. The Cobalt bits are also quite brittle being so hard.

Use a center punch (the smallest size finished nail punch) to punch an indentation right in the center of the broken shank so you can start your first drill bit centered. Start with the smallest drill bit to drill into the shank. Don't go deeper than the broken shank. You don't want to drill into the block. Increase the drill bit size one at a time until you reach the maximum bit size required by the proper size bolt extractor. Then use the bolt extractor to get the shank out.

http://i21.photobucket.com/albums/b274/yaofengchen/BMW_95_540/DSC_3117-1.jpg

Thank you sir for your help but the bolt that is broken is one of the 4 inch ones. When the bolt broke 1/2 inch remains inside of the engine block (I can't see the bolt).

[yaofeng]

I know there is on m6 bolt longer than the rest. But no matter. If you can get the parts removed to that shown in the picture, you can extract the broken bolt. I forgot which hole the long bolt goes to. You should know more now.

http://i21.photobucket.com/albums/b274/yaofengchen/BMW_95_540/DSC_2731.jpg

[Green Bimmer]

try to find a set of reverse drill bits, then do like yaofang says, sometimes the reverse bits will unscrew the part stuck in there.

1994 530i
Joe in Orlando

Recently I tried to replace my water pump but broke one of the four inch bolts in the chasis. Today I was told by a mechanic that I could use 3M Gasket Seal and put the water pump back into place and then put the glue the broken bolt back into place without any worry. He ensured me that after I did this the water pump would not leak, but he did tell me that if it leaked he would toll my car to his shop and tap the hole and charge me $100.00 (which is normally a $200.00 job).

[Blitzkrieg Bob]

he forgot the wire hanger and chewing gum.

[Green Bimmer]

he forgot the wire hanger and chewing gum.
What do you suggest? I Read all of the other suggestions and they failed to understand that the bolt is a 4 inches and not the shorter ones. I can't use a center punch because I can't see the bolt. I can't use a reverse drill the bolt broken off at the 3 1/2 inch point. So what can I do? One guy suggested that I remove the front portion of the chasis (NO WAY!).

[wingman]

This has happened to me. I drilled a hole in the centre of the bolt and inserted an 'easy-out' reverse drill. That then broke off inside the stuck bolt!!! I used a good quality drill bit as stated before and drilled as close to the same size as the stuck bolt so as just to leave the thread remaining. I then tapped the hole and stuck a new bolt in. Be really careful if you are going to tap the hole yourself. Only turn the tap about a 1/4 of a turn at a time. Good luck.

[Blitzkrieg Bob]

That bolt sandwiches the front cover to the block through the pump, removing the front cover would open up access for the repair.

I'd try the drill and easy out approach one more time.

I have seen longer drill bits (a cheap one can be sacrificed as a center punch) and tap extensions for the easy out, so it may just be a matter of finding the right tools.

And when you put it back together, use anti-seize compound to prevent this from happening again.

Good luck

[Green Bimmer]

This has happened to me. I drilled a hole in the centre of the bolt and inserted an 'easy-out' reverse drill. That then broke off inside the stuck bolt!!! I used a good quality drill bit as stated before and drilled as close to the same size as the stuck bolt so as just to leave the thread remaining. I then tapped the hole and stuck a new bolt in. Be really careful if you are going to tap the hole yourself. Only turn the tap about a 1/4 of a turn at a time. Good luck.

Thanks for your help

There is no way that I can drill a hole in the center of the bolt and insert easy-out. The bolt is 4 inches long and 1/2 inch is stuck in the hole. This is what I've been saying along. I can't use an reverse drill or easy out.

[brosher]

So it is something like this, where the side you have access is on the right....


|------------- 4" ---------------- |
|--1/2"-|
-----------------------------------
|/ / / / /{
-----------------------------------

[Green Bimmer]

So it is something like this, where the side you have access is on the right....


|------------- 4" ---------------- |
|--1/2"-|
-----------------------------------
|/ / / / /{
-----------------------------------
Thank you sir, that is it. That is exactly where the bolt is broken. Only 1/2 inch remains in the hole. I am going to purchase some Cobalt drill bits to try to drill into the bolt. I am going to mark the drill bit with the same length as the bolt I will ask for more information at the home depot hardware store. Is that what you suggest? Or did you have something else in mind?

|------------- 4" ---------------- |
|--1/2"-|
-----------------------------------
|/ / / / /{
-----------------------------------

[yaofeng]

That bolt sandwiches the front cover to the block through the pump, removing the front cover would open up access for the repair.

I'd try the drill and easy out approach one more time.

I have seen longer drill bits (a cheap one can be sacrificed as a center punch) and tap extensions for the easy out, so it may just be a matter of finding the right tools.

And when you put it back together, use anti-seize compound to prevent this from happening again.

Good luck

On the M60 engine the timing cover is sandwiched between the two heads and the sump casting. (note the sheet metal sump pan is bolted to the sump casting.) Removing the M60 timing cover is a head gasket job not for the faint hearted. I now have my M60 on the stand and I can't even remove the sump casting. Two of the four bolts on the stand are bolted to the casting.

[632 Regal]

now I follow! I read about this on here some time ago. the guy put it together without the bolt and then had even bigger problems (i dont remember what happened). even if you happen to unscrew the broken stud it will fall down, perhaps between the timing gear and chain?

might have to remove the front cover :(

[brosher]

I am going to mark the drill bit with the same length as the bolt I will ask for more information at the home depot hardware store. Is that what you suggest? Or did you have something else in mind?

So can someone clarify what type of bolt hole this is? Is it solid surface behind it or is it open to some engine cavity?

Try a local hardware store first like true value, you'll have a tough time getting anything useful from a HD employee. Either way most of us have been there. I broke off two bolts that held down the cam shaft bracket on my motorcycle. Not fun. :(

[Green Bimmer]

now I follow! I read about this on here some time ago. the guy put it together without the bolt and then had even bigger problems (i dont remember what happened). even if you happen to unscrew the broken stud it will fall down, perhaps between the timing gear and chain?

might have to remove the front cover :(

If I drill out the 1/2 inch bolt why would I have anything in the chasis if I took the stuff out with a magnet? I don't follow your example. What a nightmare this has caused me.

[Green Bimmer]

[QUOTE=Green Bimmer]Joe in Orlando
1994 530i

Now I am really confused. I was getting ready to go to the hardware store (home depot to purchase a long cobalt drill bit set to try to remove the screw). Now you guys are telling me that the screw is going to fall into the engine cavity?

[Green Bimmer]

This has happened to me. I drilled a hole in the centre of the bolt and inserted an 'easy-out' reverse drill. That then broke off inside the stuck bolt!!! I used a good quality drill bit as stated before and drilled as close to the same size as the stuck bolt so as just to leave the thread remaining. I then tapped the hole and stuck a new bolt in. Be really careful if you are going to tap the hole yourself. Only turn the tap about a 1/4 of a turn at a time. Good luck.

Was the broken bolt one of the longer ones or a shorter bolt?

[Derek A.]

If the threads are good - why not just use a 3.5" bolt and put it back together. I would assume that would give you enough holding power considering there are other bolts that hold the water pump on.

[Green Bimmer]

If the threads are good - why not just use a 3.5" bolt and put it back together. I would assume that would give you enough holding power considering there are other bolts that hold the water pump on.

WOW!!
I this never cross my mind. I will try this. Thank you. I will let you know how things turn out.

[632 Regal]

see how many turns it will thread in before you tighten the thing up and strip the rest.