engine and drivetrain Head Removal Help

[jimk]

Air nozzles were in earlier than the 72's with the 121 head and single barrel carb.  The 72's with the E12 head and 2 barrel carb didn't have them.  I don't know if the air pump system came again later.

['76mintgrün'02]

Here is a good old thread where Pat Allen put a few manifolds on a flow bench to compare them.

 

http://www.bmw2002faq.com/topic/114012-myth-buster-exhaust-manifolds/page-2

 

I bought a tii manifold to replace the boat anchor on my 76.

I suspect the tubes have been removed on my existing header, but I hope not.

I say that, because I would stand to gain more with the swap  

I doubt I will notice much difference, but I  do prefer the look of the tii unit.

[mikethevilla]

Nice. And now I'm looking at headers...You guys are the worst...

 

In other news, those dimples on my pistons mean that I need to be measuring the valve/piston clearance. Has anyone done this? What's the preferred way to go about this?

['76mintgrün'02]

Noooooo.  The point of posting that old thread was to say maybe don't even bother with a tii manifold.

Unscrew the tubes and put it back on.

 

I read another thread a while back, which basically said the exhaust is one of the things BMW did well, right from the factory and you do not see much gain with headers, until you get up over 150 hp.

[FrictionTape]

Update on my head removal and while I don't know much, I have a feeling what I found isn't good.   Started out thinking I was at TDC due to the mark on the sprocket lining up with the oil bar....yeah, wrong.  Next is what you see here:

 

1)  Significant carbon, but that was to be expected

2)  There seems to be a small hole/chip in  #1 and it had small indentations (as did valves on that one)

3)  #3 can be wiggled ever so slightly and i see a shimmer of oil around the outer edge

4) #4 had a lot of oil around it

5) All of the bolt holes were full of oil, is that normal?

6)  The valves were completely scorched

7) Cylinders themselves didn't look bad, but #1 had some decent carbon in there.

 

It doesn't look much worse than Mike's, but then again, I don't really know what it should look like either.   How do you get all the carbon off...plastic scraper and crank away?   And how serious is that hole in #1...I assume pretty since I imagine that one would be down on compression.

 

 

 

 

Edited July 21, 2015 by Z3M

[jimk]

Cyl 1 had something pass thru, probably something dropped of a non-captive (and probably after-market or home grown) part come loose and pass in the carb.  You ain't bad off.

Oil in to bolt holes is normal spillage when the head is pulled.  Clean them out until a rag is dry.

Edited July 21, 2015 by jimk

[pmg]

Also heading down this road after I blew a gasket.

 

3M makes some fancy bristle disks that are good for alluminum heads. The nubs wear down as you get through it:

 

50 Grit for the initial gunk.

 

120 Grit for the details

 

and of course the disk pad holder

 

Video here:

 

GM issued a bulletin to not use ScotchBrite as the aluminum grit can get in the oil and ruin your day. Probably a good reason to do a full coolant flusha and oil change *after* this procedure.

Edited July 21, 2015 by pmg

[Mark92131]

Z3M:

 

That motor is setup for Dual Carbs or Lynx or Cannon Manifold with the intake manifold water jacket bypass.  Whatever you are running for Carb(s), they look like they are running rich.  If you are running duals, that's a lot of carb for flat-top pistons.  Your #1 piston will need to be set at TDC before re-assembly, You can get it real close by eye or feel, then use the timing marks on the front crank pulley to confirm.  There is a line on the front of the Cam, not the Sprocket that lines up with the oil bar.  Your machinist can do this for you when the head is re-assembled.

 

Good Luck,

 

 

Mark92131

[FrictionTape]

The car came with dual weber 45s so that more than explains the major build up of carbon. Am I still in good shape with #1, even with the small chip/hole in the cylinder head. Here is a better cleaned-off picture. The hole is around 7 o clock.

As for tdc, I have the car at home so I'll be doing that....didn't see any marks beyond what was on the sprocket the chain goes around.

Edited July 21, 2015 by Z3M

[mikethevilla]

It doesn't look much worse than Mike's, but then again, I don't really know what it should look like either.   How do you get all the carbon off...plastic scraper and crank away?   And how serious is that hole in #1...I assume pretty since I imagine that one would be down on compression.

 

 

 

I have a feeling that both of us need gifs of us holding a wrench and the engine head in our hands, staring into the engine bay with giant ?s above our heads. Haha.

 

Hopefully others are more helpful than I am!

 

Unrelated side note: My previous car was a M Roadster (Z3). 

[mikethevilla]

The car came with dual weber 45s so that more than explains the major build up of carbon. Am I still in good shape with #1, even with the small chip/hole in the cylinder head. Here is a better cleaned-off picture. The hole is around 7 o clock.

As for tdc, I have the car at home so I'll be doing that....didn't see any marks beyond what was on the sprocket the chain goes around.

image.jpg

 

Oof. This looks worse than mine. 

[mikethevilla]

Also heading down this road after I blew a gasket.

 

3M makes some fancy bristle disks that are good for alluminum heads. The nubs wear down as you get through it:

 

50 Grit for the initial gunk.

 

120 Grit for the details

 

and of course the disk pad holder

 

Video here:

 

GM issued a bulletin to not use ScotchBrite as the aluminum grit can get in the oil and ruin your day. Probably a good reason to do a full coolant flusha and oil change *after* this procedure.

This was massively helpful. Thanks!

[FrictionTape]

@Mike.....that'd be an awesome gif, need to get on that! It looks like I could be in for a rebuild....or maybe a swap?!

[thinksound_mike]

Yeah I was actually considering this simply because the think is so freaking rusty. Mine is a 1972, and the manifold certainly looks old enough to be original, but at some point the previous owner changed both the exhaust and head (maybe even the whole engine), so who knows what it came off of/if it's original.

 

I was looking at various IE headers and such, but wasn't which would be best. At the end of the day, any header replacement is going to come down to how much $$$ Ken needs from me for the head work

 

Mike, you can remove the air tubes and while the head is off, take the manifold and soak it. I put a tii manifold in apple cider vinegar for 5 days and it ate almost all of the rust off. I cleaned the rest with a wire wheel and small wire brush. A few coats of rustoleum bbq grill paint (high heat) and it was looking great. It's pretty amazing how some of this stuff cleans up. But if you want to get a shorty header from IE, I certainly wouldn't stop you

[TobyB]

Yeah, #1 has eaten its top compression ring.

 

Sorry.

 

t