Andrew
07-10-2005, 05:57 PM
The car finally seems to be running well thanks to all of your help!
I torqued the bolts down to 58 ft lbs + 40 degrees.
I am still not 100% sure what I was smelling from the rear of the engine, but after driving around town for a long time (and drilling a hole in the thermostat to help me bleed the system) there is no more steam from behind the cylinder head.
As for the steam in the exhuast, I think it was just water vapor from the cool weather we were having. It DID NOT smell sweet and the check engine light went away when I re-sat the connection under the intake manifold.
A few notes about the process and the result:
You guys told me 100x to avoid bouncing the head off the timing rail guide. Well, when I got in there, it turns out that someone or something already destroyed the top 2 inches of it or so. I plan to eventually replace the plastic guide, but the car runs fine without it. I would have replaced it while I was in there, but I was not 100% sure the car would ever start up again. (This was my first HG job.)
The new cylinder head from headsonly.com arrived promptly and in good condition. It was missing intake studs, exhaust studs, and oil spray bar, and the rear cam plates and seals... so just factor in another $45 if anyone ever purchases a head from this place in the future (or reuse your old parts.) So far the engine runs VERY smooth and pulls hard... there is a little valve tick but I am going to re-check the clearances and change the oil.
I have no idea how long my old head gasket was blown. The car always drank a little coolant (maybe just from hose leaks). I used a NAPA block tester kit to convince myself that either the gasket was blown or the head was cracked. Also, the coolant level would always rise SIGNIFICANTLY when opening the expansion take cap in the morning (cold). (This could also be a symptom of a bad cap.)
The process of replacing the head was not too difficult at all. It took me about 2 weeks with just working on the car for about 2 hours each day. I am by no means an expert mechanic but most of the procedure was unbolting things and remembering where things connected. (Pictures and lots of labeled plastic baggies helped a lot!)
My father helped me do the physical lifting of the head and intake manifold out of the car. It is possible for an average person to get them both out of there without a) killing their back and b) destorying the fender on the car!
When disassembling the engine, I held up the chain and sprocket with a rope from my garage ceiling. I never removed the tensioner piston like the manual said. A tip when installing the head is just to make sure that your head is as close to TDC as possible or make sure that the dot (dowel) is slightly off in the counter-clockwise direction (if at all) so you can rotate the cam with the head on the block. (The cam does not rotate CCW) I lucked out when the sprocket lined up with the cam perfectly as I already torqued the head down the first stage!
Remember to install the exhaust manifold gaskets and spark plugs BEFORE dropping the head into the car. I left the exhaust manifolds bolted to the down pipes and made the mistake of trying to put the gaskets in after the head was down... it took 2 people, a crow bar, and an hour to get the rear gasket on (i.e. squeezing it onto the exhaust studs between the head and manifolds) And then the spark plug threads seemed a little dirty or damaged... luckily all 6 plugs are tightly in the head now but threading them into a new head for verification purposes could be a good idea.
I also destroyed two distributor rotors when trying to mount the cap. I am not sure what I did wrong, but remember to have patience and gently bolt the cap to the timing cover... I think the pin in the center of the cap cracked the circular opening on the rotor when I was lining them up.
When starting the car for the first time, I lightly lubes the cam lobes with black "Moly EP Grease" that I bought at Autozone. I also dowsed the cam in a quart of motor oil.
I replaced my fuel injectors with the 19lb Bosch "Ford" units from eBay. So far, so good.
Well, I hope I fixed my cooling problems. And, I hope some of these notes will help people replace the head and/or head gasket on their M30s... They are the least I could contribute to this forum after it helped me so much!
Thanks
Andrew
'90 535i
I torqued the bolts down to 58 ft lbs + 40 degrees.
I am still not 100% sure what I was smelling from the rear of the engine, but after driving around town for a long time (and drilling a hole in the thermostat to help me bleed the system) there is no more steam from behind the cylinder head.
As for the steam in the exhuast, I think it was just water vapor from the cool weather we were having. It DID NOT smell sweet and the check engine light went away when I re-sat the connection under the intake manifold.
A few notes about the process and the result:
You guys told me 100x to avoid bouncing the head off the timing rail guide. Well, when I got in there, it turns out that someone or something already destroyed the top 2 inches of it or so. I plan to eventually replace the plastic guide, but the car runs fine without it. I would have replaced it while I was in there, but I was not 100% sure the car would ever start up again. (This was my first HG job.)
The new cylinder head from headsonly.com arrived promptly and in good condition. It was missing intake studs, exhaust studs, and oil spray bar, and the rear cam plates and seals... so just factor in another $45 if anyone ever purchases a head from this place in the future (or reuse your old parts.) So far the engine runs VERY smooth and pulls hard... there is a little valve tick but I am going to re-check the clearances and change the oil.
I have no idea how long my old head gasket was blown. The car always drank a little coolant (maybe just from hose leaks). I used a NAPA block tester kit to convince myself that either the gasket was blown or the head was cracked. Also, the coolant level would always rise SIGNIFICANTLY when opening the expansion take cap in the morning (cold). (This could also be a symptom of a bad cap.)
The process of replacing the head was not too difficult at all. It took me about 2 weeks with just working on the car for about 2 hours each day. I am by no means an expert mechanic but most of the procedure was unbolting things and remembering where things connected. (Pictures and lots of labeled plastic baggies helped a lot!)
My father helped me do the physical lifting of the head and intake manifold out of the car. It is possible for an average person to get them both out of there without a) killing their back and b) destorying the fender on the car!
When disassembling the engine, I held up the chain and sprocket with a rope from my garage ceiling. I never removed the tensioner piston like the manual said. A tip when installing the head is just to make sure that your head is as close to TDC as possible or make sure that the dot (dowel) is slightly off in the counter-clockwise direction (if at all) so you can rotate the cam with the head on the block. (The cam does not rotate CCW) I lucked out when the sprocket lined up with the cam perfectly as I already torqued the head down the first stage!
Remember to install the exhaust manifold gaskets and spark plugs BEFORE dropping the head into the car. I left the exhaust manifolds bolted to the down pipes and made the mistake of trying to put the gaskets in after the head was down... it took 2 people, a crow bar, and an hour to get the rear gasket on (i.e. squeezing it onto the exhaust studs between the head and manifolds) And then the spark plug threads seemed a little dirty or damaged... luckily all 6 plugs are tightly in the head now but threading them into a new head for verification purposes could be a good idea.
I also destroyed two distributor rotors when trying to mount the cap. I am not sure what I did wrong, but remember to have patience and gently bolt the cap to the timing cover... I think the pin in the center of the cap cracked the circular opening on the rotor when I was lining them up.
When starting the car for the first time, I lightly lubes the cam lobes with black "Moly EP Grease" that I bought at Autozone. I also dowsed the cam in a quart of motor oil.
I replaced my fuel injectors with the 19lb Bosch "Ford" units from eBay. So far, so good.
Well, I hope I fixed my cooling problems. And, I hope some of these notes will help people replace the head and/or head gasket on their M30s... They are the least I could contribute to this forum after it helped me so much!
Thanks
Andrew
'90 535i