New BMW owner and need some advice

Hello, I am new to the forum just purchased a 2003 BMW 325i from an individual about 2 weeks ago for my wife. Car was really clean and looked to have been taken care of. Exactly a week later the expansion tank cracked. So I ordered a tank and put it on and bled the coolant system. The car was still overheating. So I took it to a local import mechanic. Mechanic says engine compression is getting into the cooling system. And that I have either a blown head gasket or cracked head or block. So I am looking at replacing the engine. I am more used to working on american hot rod type rwd vehicles, so I am kinda in the dark on a newer model BMW. How much trouble is it to swap the engines out myself? Any specialty tools necessary for swapping out the engine? Or will it be better to just pay the extra money and let him do it?


Thank you!

First things first....

Was a compression/leakdown test performed ? If yes, what exactly was indicated ?

Originally Posted by SirFatCat

Mechanic says engine compression is getting into the cooling system.

You probably do not know how many times this has happened in just the last six months alone ... so ... I painstakingly created this set of comprehensive links for the E39 crowd (most of which apply to the E46) just for folks like you!

- Summary advice to provide users who suspect a major engine repair due to overheating (1) (2) (3) (4) & how to test an engine for a blown head gasket, cracked heads, a warped block, stripped head bolt threads, cam seizures, contaminated bearings, coolant hydrolock, or piston, ring, or valve damage (1) (2) & what are the major factors in deciding whether to rebuild the engine, replace the engine, or sell the car (1) & a DIY for replacing the I6 M54 head gasket (1) (2) & replacing the V8 M62TU head gasket (1) & why these engines are so prone to heat-related damage in the first place (1) & welding the crack between cylinder #3 and the water jacket on the exhaust side (1) & what engine swaps are most recommended (1) (2) (3) & where to obtain a new or rebuilt head (1) replacement short block or long block (1) (2) & how to lift & remove the engine (1) & the most recent real-world results from the last 50 people faced with similar blown engine problems from which this advice came from (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (18) (19) (20) (21) (22) (23) (24) (25) (26) (27) (28) (29) (30) (31) (32) (33) (34) (35) (36) (37) (38) (39) (40) (41) (42) (43) (44) (45) (46) (47) (48) (49) (50)

If there is a question you have that is "not" covered in these threads, then please let me know and I'll make a link to the solution you find.

Yes a compression test was done. It pegged out the gauge. Way too much pressure in the cooling system.

Originally Posted by SirFatCat

Yes a compression test was done. It pegged out the gauge. Way too much pressure in the cooling system.

OK, Mr. Hotrod, I think what Fast Bob was asking was has a compression test of the engine cylinders been done?

No. A pressure test was done on the cooling system. Not a compression on the cylinders.

Originally Posted by SirFatCat

No. A pressure test was done on the cooling system. Not a compression on the cylinders.

If your "mechanic" makes that kind of diagnosis without a compression/leakdown test (the industry standard for this type of problem), RUN, don`t walk, to a different shop....

What else could cause that much pressure in the cooling system?

I found it odd as well. There is no coolant in the oil or exhaust.

Originally Posted by SirFatCat

I found it odd as well. There is no coolant in the oil or exhaust.

Well, if your tstat was stuck closed it would cause overheating and peg the gauge on a coolant pressure test. Tstat is $60 and a 30 min replacement