[alhusam]

Hello guys. I have been in this forum for a while as a gust and I learned a lot from you all, and I need some help with this.

I bought an M5 F90 from an auction. I repaired everything (front axial, front bumber, control arm, headlight, ..ect) and the car finally starts. but I notice a vibrations.
after some digging unfortunately I found this:













The engine block got damaged in the engine mount point. What do you guys think is the best solution.

[Gassy]

I wish I could offer advice, but I think you'll find that among the enthusiasts on this forum are not a lot of true greasy-knuckled gear heads. I admire you for tackling this project. This car, in optimum condition, is a joy to drive and race, but I wouldn't want to imagine the finesse and trial-and-error required to restore one that's been beaten up as a salvage.

[euro*]

Damn that sucks big time.... that's why accident cars are such a big gamble.

I would replace the complete engine, or get a block and transfer everything over. Welding it will be tough, and personally I would not be comfortable owning or operating such a car with a welded mount.

[nynd]

Easiest is probably getting them welded on with reinforced welds brackets. New engine block is probably ideal but will be much more involved. As long as the block isn't cracked. it's the mount you can focus on and get a good welder to possibly repair and strengthen.

[alhusam]

Originally Posted by Gassy

I wish I could offer advice, but I think you'll find that among the enthusiasts on this forum are not a lot of true greasy-knuckled gear heads. I admire you for tackling this project. This car, in optimum condition, is a joy to drive and race, but I wouldn't want to imagine the finesse and trial-and-error required to restore one that's been beaten up as a salvage.

Thank bro. I took this is as a gamble and as project for myself but I invested alot I wish can solve this issue without costing me alot. I know this car is a joy and will make it so in the next couple weeks.

Originally Posted by euro*

Damn that sucks big time.... that's why accident cars are such a big gamble.

I would replace the complete engine, or get a block and transfer everything over. Welding it will be tough, and personally I would not be comfortable owning or operating such a car with a welded mount.

I know . replacing the engine is my last solution. the issue is I dont think its easy to find a used one where I live.

Originally Posted by nynd

Easiest is probably getting them welded on with reinforced welds brackets. New engine block is probably ideal but will be much more involved. As long as the block isn't cracked. it's the mount you can focus on and get a good welder to possibly repair and strengthen.

Do you think welding it will damage or will make some distortion in the block? Im thinking of it.
For now im searching and reading about brazing it or using a very strong cold weld like belzona 1111 which I not sure if it will work.

The thing is I dont want to do a fix that will make me always think about it while driving or is pushing me back if I want to floor the car.

Thanks guys

[northtorque]

I would second the above suggestion to weld and reinforce - don’t worry about cosmetics on the block as form follows function here. This looks like a major stress transfer point and needs to be really strong. I would also wonder if that let go with the engine movement in an accident then what stress deformation went down through the tranny and transfer case - as a result of the engine movement relative to unibody/ frame... Look closely at those points of contact on other drivetrain areas as well for damage. I’m not a mechanic, just an ex farm kid with an engineering mind. I would assume you have done a full alignment but if not double check that as well - if it is really out of sorts then it might suggest a whole bunch of hidden surprises possible? Best of luck and I hope it works out!

[r33_RGSport]

OP, you got this far already.
I would get a short block and fix it properly so you can have full confidence in driving the car.

The engine block is cast aluminum.
Once it took a lot of impact, it won't be as good as new.

Welding will fix the surface, but any hairline crack that is not visible, may and will cause issue down the line.

Again, you got this far already, I won't turn back.

Great job btw.

[JK-M5]

That'll weld up no problem, seen a lot worse in my day 2 day job and a long as it's done buy a professional it'll hold no problem, you could even weld the mount in place for additional strength,

[HMN]

Sorry to hear that. Since you're close by in Oman i'd advise you to contact Munich Motor Works in Dubai, see if they can give you advise on such a matter. If you can send it to them via recovery and see what they can do.
Good luck!

[Salespunk]

Based on the cracks still in the block I would not run it. Will be way more expensive when it blows a piston through the bottom of the motor.

[boredM]

Personally, I wouldnt run it
BUT
Either way probably a good idea to check it before and after welding via magnuflux?

[alhusam]

Originally Posted by northtorque

I would second the above suggestion to weld and reinforce - don’t worry about cosmetics on the block as form follows function here. This looks like a major stress transfer point and needs to be really strong. I would also wonder if that let go with the engine movement in an accident then what stress deformation went down through the tranny and transfer case - as a result of the engine movement relative to unibody/ frame... Look closely at those points of contact on other drivetrain areas as well for damage. I’m not a mechanic, just an ex farm kid with an engineering mind. I would assume you have done a full alignment but if not double check that as well - if it is really out of sorts then it might suggest a whole bunch of hidden surprises possible? Best of luck and I hope it works out!

I checked the tanny it looks ok. Havent test drive it so idk. I just moved it a bit. Im also a mechanical engineer .

Originally Posted by r33_RGSport

OP, you got this far already.
I would get a short block and fix it properly so you can have full confidence in driving the car.

The engine block is cast aluminum.
Once it took a lot of impact, it won't be as good as new.

Welding will fix the surface, but any hairline crack that is not visible, may and will cause issue down the line.

Again, you got this far already, I won't turn back.

Great job btw.

thanks bro. I did find a block from scrap yard. Will change it and see whats the results.

Originally Posted by JK-M5

That'll weld up no problem, seen a lot worse in my day 2 day job and a long as it's done buy a professional it'll hold no problem, you could even weld the mount in place for additional strength,

I dont know but Im not that comfortable with welding it. but as I said above I will change the block.

Originally Posted by HMN

Sorry to hear that. Since you're close by in Oman i'd advise you to contact Munich Motor Works in Dubai, see if they can give you advise on such a matter. If you can send it to them via recovery and see what they can do.
Good luck!

the car actually in Al sharjah.

Originally Posted by Salespunk

Based on the cracks still in the block I would not run it. Will be way more expensive when it blows a piston through the bottom of the motor.

Originally Posted by boredM

Personally, I wouldnt run it
BUT
Either way probably a good idea to check it before and after welding via magnuflux?

thanks all. will update you next week

[Archimedes65]

Crossing my fingers that this all works out for you. I agree with the decision not to weld.

[alhusam]

Originally Posted by Archimedes65

Crossing my fingers that this all works out for you. I agree with the decision not to weld.

It will work. If not i will find another solution. At the end I will drive this car every day and will enjoy it in a matter of weeks.

[Pimpsy]

Good call on how to proceed. Even if the block itself wasn't obviously cracked you have no way of knowing how stressed or tweaked it actually is. Considering you can see actual damage on the block, replacement is a no brainer.

Wishing you luck and success!

[alhusam]

Originally Posted by Pimpsy

Good call on how to proceed. Even if the block itself wasn't obviously cracked you have no way of knowing how stressed or tweaked it actually is. Considering you can see actual damage on the block, replacement is a no brainer.

Wishing you luck and success!

Many thanks bro. The only thing remains in my mind is it going to be as good as stock after opening the engine and changing the block. Is the workshop going to do it perfectly although the car is in one of the best workshops around here that only works in german cars.

[Pimpsy]

Originally Posted by alhusam

Many thanks bro. The only thing remains in my mind is it going to be as good as stock after opening the engine and changing the block. Is the workshop going to do it perfectly although the car is in one of the best workshops around here that only works in german cars.

No, it will never be as good as stock but hopefully it will be good enough.
Getting the right mechanic to do the work will push the odds in your favor.
GL!