How to replace your coolant pipe, valve covers, timing gaskets and more

As of right now, the problem has returned. My engine still overheats with coolant loss, but I haven't noticed any leaks whatsoever. I've replaced everything except the waterpump.

Any water in your oil?

Sent from my ADR6425LVW using Bimmer App

thanx, I do not know if the V12 has less space inside the V than the V8 but it is very tight in there, I will strip the valley cover off today, I spend half a day yesterday to remove the 12 injectors, two were stuck like anything, I was so glad that the second injector I tried to lift out came out very easy otherwise I would not have known how to get them out. In the end I just took my time, spray a lot of Q20 oil and left the oil to soak in, then I rotated the stuck injector sprayed again, waited again until I could them all out. I will definitely replace the o-rings as well.

I am in the same boat than you, I can not see were my water is disappearing as well, hence my reason to work towards replacing the water pipe inside the V. The previous owner has replaced all the radiator water pipes as well as the complete radiator to try and solve the water issue. I am hoping to find something definite else I will have to look at the alternator o-ring next.

Originally Posted by Keif

Any water in your oil?

Sent from my ADR6425LVW using Bimmer App

No and I changed the oil yesterday.

Well I did th "coolant pipe" project and my problem returned 2 days later, so I'm pulling the intake again.

Hey guys got a couple of questions on the coolant pipe repair. I have a puddle of constant flowing green antifreeze coming from the weep hole(class III Leak) and I looked all over the engine for any other areas of leakage. I know it's the coolant pipe because it just started when the weather got hot as hell here in Dallas to just start to drip out a little. It's over 100 degree + days, and the engine taking on all that extra heat probably just disintegrated that cheap seal in the front on the pipe.

Gonna get my kit from bmwpipe.com, waiting on the mail, and wanted to know when I remove the intake manifold is there a gasket under there that needs to be replaced when you go to put it back together to not cause any air leaks? And is there a torque specification when tightening up those 10 nuts?

I use to be a mechanic in the military so I know I can do it in a couple of days because I won't be in a rush. That's all I can think of for now and know I will probably have more along the way but hopefully not too many because Wilson did a hell of job documenting his journey to the dark side, lol.

HELLO, i have been reading the post about this weep hole repair, i keep seeing the reference to the all german pipe,

two things where can i get one and also have anyone heard of the bimmerpipe? any opinion there thanks

I have the rt side loose but I do not seem to have enough room with the break lines and ac line how do I free up more room? I managed through the rt side valve cover, timing cover and alt bracket. Not fun but didn't rush.

I've had a coolant leak for several months now and since I was going on vacation for a week I decided to drop my 2006 750I with 116,000 miles off to my Indy shop. My Indy mechanic is my 28 year old son who has been taking apart cars since he was a kid. A real prodigy.

The first step was to pull the exhaust and drop the tranny to get to the coolant cover by the block. He had access to see if it was leaking but it wasn't but we decided to replaced it anyways since he was there and I had the part.
The second fix was to put the tranny on the stand and to inspect the GUIBO joint. It was shot. He couldn't believe that I could still drive the car. This wear and tear caused a load bang when downshifting, especially between 2nd and first gears.
The third fix was to take the intake apart and get to the valley pan gasket. Sure enough, that was where my coolant leak was. Here is the fix that he did without having to buy the $450.00 tube kit.
He bought a new tube since the dealer doesn't sell the o-ring separate, He took the o-ring off the front part of the tube. He cut under the adhesive to remove the o-ring from the tube since it was glued on. He then inserted the pipe from the rear of the valley pan, instead of the front. He used a windshield adhesive to glue the o-ring back to the front part of the tube and let the adhesive set over night. He also used the same adhesive to put the valley pan cover back on. Next day, put the intake back on, exhaust, and tranny back in the car and finally I have the ultimate driving machine with no smell of coolant or no more fast jerking downshifting.

Originally Posted by fratan

I've had a coolant leak for several months now and since I was going on vacation for a week I decided to drop my 2006 750I with 116,000 miles off to my Indy shop. My Indy mechanic is my 28 year old son who has been taking apart cars since he was a kid. A real prodigy.

The first step was to pull the exhaust and drop the tranny to get to the coolant cover by the block. He had access to see if it was leaking but it wasn't but we decided to replaced it anyways since he was there and I had the part.
The second fix was to put the tranny on the stand and to inspect the GUIBO joint. It was shot. He couldn't believe that I could still drive the car. This wear and tear caused a load bang when downshifting, especially between 2nd and first gears.
The third fix was to take the intake apart and get to the valley pan gasket. Sure enough, that was where my coolant leak was. Here is the fix that he did without having to buy the $450.00 tube kit.
He bought a new tube since the dealer doesn't sell the o-ring separate, He took the o-ring off the front part of the tube. He cut under the adhesive to remove the o-ring from the tube since it was glued on. He then inserted the pipe from the rear of the valley pan, instead of the front. He used a windshield adhesive to glue the o-ring back to the front part of the tube and let the adhesive set over night. He also used the same adhesive to put the valley pan cover back on. Next day, put the intake back on, exhaust, and tranny back in the car and finally I have the ultimate driving machine with no smell of coolant or no more fast jerking downshifting.

Can you explain further or aves pix? This sounds very interesting about his fix...if no pix maybe a drawing?

Can't take any pictures now that the valleypan is back in and put back together. My son is an amazing mechanic, 28 years old, gifted. He fixed my wifes 745i this weekend by replacing the bridge seal adapter inside the tranny. I called the distributor for ZF transmissions and he said that 99% of the time the bridge seals crack and needs to be replaced. We were getting the 507c, 507b, 4F97 codes in Inpa. After fixing the bridge seal the codes cleared themselves. Car has a lot more power because the crack adapter seal is a pressure loss causing all kinds of codes.

Getting back to the coolant fix, he bought the valley pan tube from the dealer and at the end it had an o-ring. Instead of coming in from the front of the car and taking apart all that crap he had access to the back of the engine block because the exhaust and tranny was taken off to fix the coolant cover on the back of the engine. That cover wasn't leaking but we replaced it anyways. He cut the o-ring off the tube and was able to install the tube from the rear of the engine block and then glued the o-ring back on with windshield adhesive. Then made the valley pan seal with the same stuff. I've been running the car now for a couple months and not a drop is leaking.
All I have left to do is head gasket and tranny change with new bridge seal.

Got it ...you're a blessed man