Author Topic: Somethings wrong. (Read 18898 times)

elementskater_xx · « **Reply #45 on:** June 13, 2008, 01:59:53 PM »

Quote from: nomad;51211

for reference:
http://www.esatclear.ie/~bpurcell/318istimingchain.html

Cam gear bolts are not centered, when it is all put together right they will be centered.

Use the trick I posted to hold your cams with the rear flats even. In the photo your exhaust cam is off, not flat, it looks a bit anti-clockwise and the intake cam looks a tiny bit clockwise, see how it's not even with the valve cover mounting surface?

All you have to do is take off the cam gear bolts and let them slide off the cams, then realign. I did the same thing you did the first time and puzzled over it, then adjusted it, tried again and it was right.

What is really important is if you have the cams themselves in the right position to begin with: front lobes pointing towards each other

When the cams are in this correct position
and
When the flywheel is at TDC
and
When the flats of the rear lobes are clamped firmly in a perfectly flat position
and
The tensioner is not applying force to the chain
then
The cam gears will go on in a perfect alignment with the cam gear bolts truly centered in the cam gear elliptical holes.

15 rivets inclusive from arrow to arrow is correct, but remember that you may be one tooth off on both cam gears if they are not lined up correctly.

BTW
The head looked nice to me and the block seems ok. Not sure if you bent rods as mentioned before from having the coolant in the cylinders. Other than that I hope it goes well.

Post pics when you get it all timed up.

EDIT:
I think you may just need to loosen the cam gear bolts, reposition and lock the cams and you may be good to go.

So you want me to loosen bolth cam sprockets. Readjust my exhaust counter clockwise. Then adjust my intake cam clockwise a hair? When i put a pencil on the cam squares it looks straight. And should i turn my sprockets a tooth clockwise or counter clockwise?

nomad · « **Reply #46 on:** June 13, 2008, 02:34:42 PM »

EDIT
If it is just the photo that is making it look off and they are indeed totally straight then you are off a tooth.

The more I look at it the more I think your exhaust cam is anti-clockwise by a fraction.
Loosen the exhaust cam gear but leave it on, use a wrench on the square flats and adjust it clockwise a bit. You may be able to get the bolts centered then.

The intake cam is only a tiny bit off so you may be able to do the same.

elementskater_xx · « **Reply #47 on:** June 13, 2008, 02:40:09 PM »

Ok i just moved the cams a bit and the holes lined up good. I am not sure if i am tooth of. It looks identical to the book. It's hard to tell with pics you posted cause they are taken off to the side. There is still a noise when i turn it. Like something is under preasure. I am going to mess with it a little more hen i will get back to ya.

peerless · « **Reply #48 on:** June 13, 2008, 03:02:29 PM »

Maybe this picture will help out. What I have noticed is that when you have one of the cam bolts centered the others are not centered.

This was assembled with a cam locking tool. On the second M42 I just did I got the same result, even after playing with it. I would not worry if the bolts are not all exactly centered as I don't think its possible.

Element, if your sure your cams are dialed in and the chain is on tight with no slack between the gears and from the intake to the crank, you should be fine. All slack should be on the tensioner side. As a side note, I use locktite on all the cam gear bolts.

First M42

Second M42. You can clearly see 2 cam bolts are centered where the others are off-set.

nomad · « **Reply #49 on:** June 13, 2008, 03:02:34 PM »

pics needed element.

Great pics peerless. Where'd you get those fancy "blue camo" gears?

Noise is probably normal.
Everything in there is under pressure. You've got pistons sliding in bores, bearings, valves, springs, cams etc.

I highly suggest you drop the oil pan and take a look at the rods to see if anything looks strange down there before firing it up.

If you have the rear flats even and the front cam lobes pointing towards each other and the bolts centered in the cam gear slots then you're in good shape.

Make sure to put a dab of medium locktite on the bolts so they don't loosen up. That's what i read and did, not sure if it's critical though.

elementskater_xx · « **Reply #50 on:** June 13, 2008, 03:21:17 PM »

I would love to take some pics. But my girlfriend has stolen my camera for the beach. But my head looks just like your pic. Only sideways. And what do you mean by pointing each other? Slightly pointing at each other? Or directly dead point of lobes facing at each other? Like your fingers on each hand facing each other?

nomad · « **Reply #51 on:** June 13, 2008, 03:37:12 PM »

I mean just like the pics I posted with the red circles on them.
That's from the website I put a link to.

You're probably good to go. Check that bottom end though.

peerless · « **Reply #52 on:** June 13, 2008, 04:02:34 PM »

Nomad wrote:

Quote

Great pics peerless. Where'd you get those fancy "blue camo" gears?

LOL, those are brand new cam gears from BMW. The 'blueing' you see is from the hardened steel. The 'camo' effect you see is from my oily fingers.

elementskater_xx · « **Reply #53 on:** June 13, 2008, 04:11:37 PM »

Ok so it looks identical to the pics posted above. I even got a second opinion, just cause my eyes hurt from looking at this all day. Thanks for your help. What do you mean look at the bottom end?

nomad · « **Reply #54 on:** June 13, 2008, 05:11:35 PM »

I'll quote myself.

Quote from: nomad;51223

I highly suggest you drop the oil pan and take a look at the rods to see if anything looks strange down there before firing it up.

elementskater_xx · « **Reply #55 on:** June 13, 2008, 07:57:34 PM »

Ok well after messing with it some more. I am kinda back to where i was. The back squares are def flat and the front lobes are def looking in the right spot but the holes are not lined up. I am at a loss. I am wating for my girl to show up so i can get my damn camera. Will take some pics soon and send em your way thanks again.

nomad · « **Reply #56 on:** June 13, 2008, 08:28:46 PM »

If the bolts are totally to one side of the slots on each cam gear then you have them off by one tooth, both should move and you'll be good

elementskater_xx · « **Reply #57 on:** June 14, 2008, 07:56:17 PM »

Well I am almost posotive i got it. The center bolts are not completely centerd but close. I also put the pencil on the back squares and it's flat. Also the #1 piston lobes are facing each other. Well kinda mora like a triangulaur shape. But it looks just like the pictures i have seen. I have it all back togethor> I have to wait till tommarow to fire it up tho. I cut my exhaust to get the manifold back on on. So i gotta get some pipe to fit it. I wish i could get some pics on here but i have not been able to locate my camera. Thanks for everyones help. Maybe someone can post a pic of what thier back cam suares look like with a pencil across the, and maybe a frontish pic of thier #1 piston lobes. That would be great.

elementskater_xx · « **Reply #58 on:** June 14, 2008, 09:53:49 PM »

I am also wondering on the exhaust cam should the arrow sit right in between the 15th and 16th link or dead on #15 from the intake cam arrow? That will def clear up alot of confusion i have. In my Haynes manuakl it shows right dead on the 15th. In the pic above it shows it dead on. But in a couple of other pics i have viewed it shows it in between.

Cobra Jet · « **Reply #59 on:** June 14, 2008, 10:03:36 PM »

before you start it up (again), I would definitely check and recheck (even if you are getting a headache) just so your are 100% certain everything is in place, torqued and aligned appropriately BEFORE firing it up.

Try contacting bmwpower on here via a PM, he reassembled my M42 and can probably help out as well. I think I recall him stating the same that the cam gear bolts were not 100% "centered" - I could be wrong or right, so do PM him as he surely would be able to check out this thread and possibly assist (if he's not too busy). In fact, I'm pretty sure he has digital pics of my M42 as he was assembling it too... probably another version or possible same or better than those already posted (based on angles, etc).

One other thing, did you determine what the "pressure" was when manually cranking over the engine? You mentioned it a few times and I'm just wondering if you checked all areas as recommended by others before you fire it up - have you found out why you have a slight "squeak" or "pressure" - if so, what was the problem?