Bought a 2004 330ci with about 120,000 miles that had been severely overheated. I got it from a BMW shop and he explained to me that there is a chance the threads in the block have been damaged due to being strained by the thermal expansion. I tried to pressure test the cylinders but they couldn’t hold pressure. I think it was like 100psi in and 30 psi in the cylinder. Could hear hissing out the other cylinders.
Through my research it was stated that all the head bolts need to be broken loose and retorqued then 90 degrees and another 90 degrees to check the threads.
my question is can I do this with the already yielded head bolts or do I need to get a new set? I’d get new ones if I replace the head for sure.
My thoughts are if they check out good, just replace the head. That is if the block deck is good and if there isn’t any coolant in the oil. That would cost around $450 for the head.
Otherwise, get an engine from the auto salvage is SoCal for about $1200-1500. I’d be doing all the work in my garage
I’d appreciate your feedback.
Thank you,
Bob
If memory serves the torque on those is torque angle. Certain lbs plus 1/2 or 3/4 after turn Or percentage . Some specs on some cars use percentages. Which just makes us need to buy more tools. This stretches the bolts or studs. ARP studs are meant to take this and be reused. Original bolts are meant to be discarded and replaced after use.
I would get another engine.
Thank you for your input Yaser. I think it might be easier and reduces a lot of risk.
Once again thanks,
Bob
You're welcome Bob. Good luck.
I would remove the head and have it rebuilt. I would try to fine ARP head STUDS, not bolts. Get a bottoming tap to clean up the threads in the block and put it all back together.
Doc, thank you for this suggestion. It is something I wasn’t even aware could be done.
I am leaning on just swapping the whole engine out which will leave me am extra engine, this over heated one. I was thinking of rebuilding it then put it in my other 2005 330 Bi convertible, possibly supercharging that one.
I appreciate the feedback. It is increasing my knowledge of possibilities.
Bob