Bad Cylinder Head - now good, but rod knock?

[rtwaits]

So I bought a car with a probable blown head gasket. 1989 325i Convertible. Engine overheated last month before I bought it - it was not driven since then (other than this video of it idling, and another time to get it on and off a transport)

http://www.youtube.com/watch?v=0OMFqEcwUF8

There is oil in water (grime in over flow tank) and water in oil (chocolate milkshake under oil cap, and on dipstick). White exhast. Coolant low. It can hold an idle but effectively stalls the second you blip the throttle.

There is also milkshake oil down the intake side of the engine, with tiny puddles in the freeze plugs of cylinder #1 and #2. No obvious leaks from the valve cover gasket. I havent removed anything yet (gathering parts and hopefully some knowledge)

I have done timing belts and wheel bearings, but never a clutch or head or engine. Figured I was advancing my knowledge a little bit. I am guessing the head could be cracked - I plan to have it checked and decked.

Some advice given was to inspect the rod bearings. Obviously I remove the pan, but what am I looking for?

I was hoping to get away with a simple head gasket replacement and a few (14!) bolts, but it's looking like I need to do a bit more

[Cabriolet]

you can do it right or you can do it cheap.
here a light over view if what i did.

http://www.r3vlimited.com/board/showthread.php?t=192482

do it right: pull the whole engine out.
heres a short list.
new water pump
new timing belt+ tensioner
ARP head studs
genuine BMW head gasket
full upper and low gasket sets.
all new V belts
new fan clutch
new thermostat
new spark plugs
new intake boot, breather hose
new water hoses
new fuel line
bmw coolant
5gal distilled water
2-3gal oil
2 oil filters
CLR
3gal of purple power or simple green max
200 man hours.
+maybe a new head if that one is bad, have it pressure tested/checked for flatness.

[rtwaits]

Nice rebuild! A bit beyond my means...

I am looking for both cheap and right! I had planned on upper gaskets, pump, timing belt and tensioner, new head bolts, thermostat, plugs, and assumed the hoses needed replacing for age, as well as contamination. Already bought BMW coolant (yikes!).

So my question is about the possibility of "rod knock". Is it possible to replace rod bearings without removing the engine? Or should I simply do the top, run it and listen? Will it be obvious?

[Cabriolet]

get stethoscope and listen to the block near the oil pan. you will hear it loud and clear if you do, it will be a scraping clunking noise.

[5KWattson]

R&R motor for used one out of crashed car...cheap, less time, less money. you know it ran when it was pulled due to...cars that dont run cant be crashed out hit(in traffic of course)

[rtwaits]

An update (of sorts, and rather lengthy - I may need to change the title of the thread to dumb-ass... see below - trying to take my time, but in retrospect I seem to be making some dumb mistakes or taking some dumb chances). I am in upstate NY, the car is nearby, but not in my garage - the place has a lift and some heat (no water!)

Anyway, I have largely been unable to find wrecked E30s. They must crush them all around here (I have called over a dozen junkyards).

So I get a rebuilt head and tear apart the car. Head bolts were surprisingly easy to remove. The old gasket looks fine, too. A minor chunk (1/4 inch) out of Piston #6. hmm. A friend said file the sharpness down - it was all on the surface of the piston. It is ok, move on.

In reassembling, the new timing belt was a bit stubborn but I did get it on. HOWEVER, I stupidly forgot to turn the engine 2 rotations! I did line up the cam shaft sprocket with the mark on the head, and the OT mark on the crank pulley with the timing belt cover mark. I went to do the valve adjustment (the new head had a note on it saying it was needed - the eccentrics were loose, so I adjusted them (.012 inches (12 thousandths)). I rotated the engine with a wrench on the crank (no spark plugs) and there did not appear to be anything binding. I followed the firing order. As I did each pair of valves, the lobes were pointing down and the rocker was not pushing on the valve. In doing the Math (I was always good at algebra but not geometry), by definition would I have rotated it twice since I did all the valves? I know that may be moot since I didnt recheck the marks - aggh

After (finally) reassembling everything else, I filled with 10w30 oil and straight water and fired it up. It cranked for about 30 sec - getting fuel I presume, then fired up. Ran reasonably smoothly (I have a bad intake boot) for a few minutes - the valve noise was very loud, however. There was also some light smoke wafting from the exhaust manifold area ( I will double check the mounting studs/nuts, but was told it was "burn off" and it continued a little after shutdown). I then shut it off (voluntarily - it didnt stall) and drained water from radiator and block (probably only 6 of the 8 quarts I added came out however). The sludge leftover from the previous problem oozed out at the end. It was late and I had ignored my family all weekend so I went home.

I am very concerned about the loudness. Brother in law says it is not a rod bearing (he's worked on cars a very long time; not BMWs though). I did not see anything obviously bad when I removed the oil pan (but I did not remove the rod end caps - yes I should have checked the bearings for play, bluing or scorching).

Did I bend a valve? that would be horrible on a new head!

So. after some searching the forums, I am writing again. I am guessing one of three things:

1) Mechanical problem - something misaligned or misadjusted
2) oil problem - everything lined up but there is no oil on the top end
3) something is broken, like a valve or rocker, or?

Next steps when I get back to the barn:

1) Check timing alignment ASAP. Rotate through 2 revolutions. If out of whack by a little, which way do I move it? What if out of whack by alot (180 degrees)?

2) Remove valve cover.
Check for evidence of oil on the rockers for the back cylinders - (the front two should have oil as I poured in 5 quarts and that's where the oil cap is)

3) check that the rocker spring clips are secure and pointing the right way (there is a thread on that but cannot readily find the link)

4) check that the bracket in front of the rocker shafts is in there -
http://www.r3vlimited.com/board/showpost.php?p=2480572&postcount=8

It seemed pretty easy to fit the 4 black rubber stoppers in the head - but I did not know about this bracket until I read that post. Are the front two difficult to put in?

5) re check the valve lash

6) check that I reconnected the oil pump drive shaft correctly so that I know I have oil pressure - http://www.r3vlimited.com/board/showthread.php?t=213362
This method turns the oil pump - does not say how to remove intermediate shaft
however.

7) Get an oil pressure gauge kit (Harbor Freight is my friend).

8) get a 4mm socket and drive that pump?

9) stick to oil changes?

[LJ851]

Leakdown test the engine and then check your timing marks.

[Cabriolet]

to start (.012 inches (12 thousandths)) is wrong. you need to me at .01" not .12" that's gonna make hella noise right there.

What if out of whack by alot (180 degrees)? thats ok. the car will run very poorly if at all if its 1 tooth off. the crank turns 2x for every time the cam rotates ones. so it will either be dead on or 180degrees off.

take a vid of the car running

[rtwaits]

I took an early lunch hour today. pulled the distributor cap and upper timing cover and valve cover. Rocker arm clips seemed secure. The little bracket at the front of the rocker arm shafts was in place. Only a little bit of oil was at the base of cylinders 1 and 2, the rest seemed dry. (?!)

Rotated the engine to TDC based on the cam sprocket. UH OH. The crankshaft sprocket was THREE teeth behind! I rotated it another 720 degrees (it did not seem to bind the entire time, though I am only turning 20-odd degrees with a long hand wrench.

Same result, as expected. Now what? I also saw my mistake with the valve clearance (warm vs cold), but the timing is the major cause of the problem!

At this point, I am guessing I broke something. I can really hope that I am just barely hitting something and just disconnect the belt, advance the crank three teeth and reassemble to see if the noise is still there. I will get a video/audio this time.

This does not explain that I have a tiny puddle of clean oil near Cylinders 1 and 2, but nothing in the others. I may have not re-assembled the oil pump drive shaft correctly, but it did seem to engage (by feel) befoire I bolted in the pump body.

I also used RTV on the oil pan gasket - is it possible that it clumped up and fell off and blocked the pickup? Can I find this out by draining the oil? I did spray the strainer out with carb cleaner and emptied the pan of sludge. Or is the evidence of oil in the valve area not completely obvious (yes I know this problem is secondary to my timing)

Thanks for your patience and help everyone!

Ross

[rtwaits]

New Update:
A friend and long time BMW enthusiast came by. Timing indeed off, by one-ish cam sprocket tooth. Also one eccentric was loose, and another one was well over the (incorrect) 12/1000ths that I adjusted it to. So we set the crank to TDC, peeled off the belt, advanced the cam and replaced the belt. Rotated it through several turns, readjusted the valves (10/1000ths!) and cranked it without the fuel fuse in it. Sounded VERY quiet. Then put the plugs in and started it up. Wonderful!

Oil (still a bit murky) was getting to all the cylinders from the oil pipe above the valves, and it seems that I finally am headed in the right direction. Might need to change the oil a couple times rather than once, and it may take a few coolant flushes to really get everything out.

[rtwaits]

OK, maybe premature - Can someone take a listen?

http://www.youtube.com/watch?v=okzx-xpNewk

http://www.youtube.com/watch?v=-FPNhp-dZpc

Ive been flushing the water out - I have not changed the oil yet.

[dnguyen1963]

Is that vapor coming out between the head and the block? It looks like the head is warped.

[rtwaits]

Head is brand new. Rebuilt by a local BMW shop. It is very pretty. Steam is from previous spill of water on exhaust it is the knock I am concerned about.

[rtwaits]

Latest update via you tube - advice appreciated!

http://www.youtube.com/watch?v=plFoQ42fMbg


After new valve adjustment (old was too tight) and compressing and reattaching a couple rocker clips. with a stethescope you can hear the that bit of knock, but it is not low pitch and is not louder when you go under the car and listen at the block or pan.

I am not excited about doing the rod bearings.

[rtwaits]

These sound like rod knock...

I found these examples on you tube. I would say they sound like rod knock. My engine does not sound like them.