72 3.0CS 3.5 Engine rebuild

m5bb

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So it begins.
I've been collecting parts for over 3 months getting ready to start this project.
Hoped to start sooner but some parts took longer to arrive.
I was going to start a month ago but then the trip to Amelia Island Concours came up and decided to wait.

Drove car last time on Friday to move to garage bay with drive on lift.
Yes, I'm spoiled I have a lift. But I'm also 65 and crawling under cars is just not fun any more.
I have some pictures but did not detail every nut and bolt. If you need that much detail you probably shouldn't tackle this job.
Started underneath with down pipes from exhaust manifolds. Sometimes you can get stopped right there when rusty nuts won't come off. PB blaster is your friend.
Next was drive shaft. Center bearing needs to be loose to allow drive shaft to flex in the middle to get it out of the end of the transmission. Of course the flex joint (Guibo) has to come loose. Pay attention to the way it is oriented so you can put it back correctly.
Let me just say right here that a camera or cell phone camera is great to document how things are before you take them apart. I also buy Zip Lock bags that have a white space on them to write on so you can label all the nuts and bolts you will have. If it's too big for a zip lock get some small boxes. Remember my 65 year old memory is not as good as it once was.
Next was removing the bolts in the bell housing that hold it to the block.
I elected to take the engine out without the trans and bell housing.
I did my M5 engine 5 years ago with the trans attached. The engine was almost vertical when I lifted it up and then had to use a come-a-long to pull up the trans to get it over the fender. Whew, that was hard work.

You will need to loosen the support bracket for the trans to lower the back of the trans to get access to the shifter linkage. Couple different ways to take this apart. May depend on which trans you have. I have 265 5sp.
Now comes one of the hardest parts. Getting the bell housing bolts out.
IIRC I had 5. Remember you lowered the trans to get the shifter out so now this will allow you access to get the top bolt. It's 17 mm and takes about a 3ft long extension and some muscle to get loose. Usually you can see it from the top at the back of the cyl head. My grounding strap was attached there.
Now if you notice the bell housing/block of the engine is resting on the long tie rod that goes across from wheel to wheel. This is ok and won't hurt anything.
But once the bell housing separates from the block the transmission will want to fall towards the floor at the front. So be prepared to put a block or something under it or it may swing down and the tail may bend your trans tunnel near the shifter.
You will also have to take the clutch slave out of the bell housing. You can just let it hang or use a tie to attach it.
The throttle linkage may be easier to disconnect from the bottom.
Motor mounts need to unbolted.
You can take the AC compressor loose from its bracket and it will remain in the engine compartment, this way you will not lose the freon.
Same way with the PS pump. I took the alternator out because I had trouble getting the PS pump out with it there.
Back up top you will have to remove the radiator (good idea to do this outside before you even bring the car in. I hate the smell of antifreeze)and disconnect everything else.
Battery cable, connection to alternator, connection for oil pressure sender,
conn. for elec chokes, fuel line. Hoses to heater core.
Probably more but you get the idea.
Once you get the hoist hooked up it's a little tricky getting the lifting angle just right so the engine will separate from the bell housing.
It took a couple tries here and a big screw driver helping the separation.
Please, put a board or something substantial in front of the AC evaporator so you don't ram the front pulley into it when the engine comes loose and swings forward. You can see one in my photos.
Once you lift it off the motor mounts you will have to do some pulling and wiggling forward to get it to come loose from the bell housing.
Once it's loose I found it helps to swing it ccw so it will lift out of the hole and not scar up your firewall.
Once I got it out I went and got the engine stand I had purchased a month before and had to put it together only to find it was missing one wheel.
Oh crap!
The engine is on the stand anyway because I was not going to leave it hanging from the hoist.

Picture time. Cell phone quality for tonight. Sorry the garage is a mess. I now have 3 motors at different stages.

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Stevehose

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Thanks for starting this thread, based on your knowledge of rebuilding your m5 engine, it's going to be a most excellent read.
 

BimmerBud

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My hat's off to you, my fellow 65+ Blue Coupe homie from the Big A. I'm impressed you're tackling this job by yourself and can only aspire to be able to learn from your expertise. I'll agree with E911 in that you're fortunate to have such a wonderful workspace. Thanks for your offer to get dirty...be careful what you ask for.
 

m5bb

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I've gotten a lot done and behind on my picture posting but thought some eye candy might be nice.

My 10.5:1 pistons arrived.
Thanks Paul Burke.

Pistons_zps7e0663f9.jpg
 

Dave G

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Great summary!

I am preparing to begin restoration of my drivable 69 2800 CS and have been debating what to do with the engine and carburetors.
- Are you adjusting the stroke and bore on your 3.0 to bring it to a 3.5?
- What carburetors are you using?
I can use all the inspiration I can get and any part specs and details you are able to share.
 

m5bb

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m5bb

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Any Dyno or performance #s?

No dyno yet. But I will get there later.
Still tweaking the Webers.
Had to go up in size and chokes.

Running a wideband AFG gauge to get my numbers.

Yes, no muffler in the video but the iphone kills the sound.
 

HB Chris

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Gary, entered in the Concours? I would love to see how many cars in each category, the listing is limited to registered members only.
 

m5bb

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No Chris, my car is a project and certainly not Concours quality.
It was painted years ago but lousy paint job with many issues. Yuck.

I see there are only 13 cars entered to be judged and 82 for display including mine.
This is totally my opinion but clean car contests are not really much fun.
You could bring a Toyota and if it was clean enough it could win. This isn't really true but I think you get my point.

Working on all the mechanicals on my car and then will disassemble and do the body right. Maybe next winter before I run out of energy and enthusiasm.

Are you coming? Didn't cruise the list very carefully. Over 500 people are signed up. That's great for Ofest with no track.
 
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