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-   -   WTF am i doing wrong. Rocker issue (http://forums.pelicanparts.com/911-engine-rebuilding-forum/999082-wtf-am-i-doing-wrong-rocker-issue.html)

Tori 06-09-2018 05:16 PM

WTF am i doing wrong. Rocker issue
 
Putting my 3.2 back together after re-ring, and head rebuild.

At the point of installing rockers. Cam timing is done, and started with #1 exh. rocker so i could measure valve to piston clearance as per Waynes book.

Once #1 exh. rocker is installed, engine will not turn over as that piston starts hitting the valve. Engine rotated fine prior with just the #1, #4 intake rockers installed.

I've installed #4-5-6 exhaust rockers with no issues and engine rotates fine. I've measured the valve to piston clearance on 1-2-3 intakes, (4.25mm-4.75mm)

Where should i start looking ? I don't know what would cause this. I have to assume cam timing is not correct.

snbush67 06-09-2018 06:46 PM

It’s got to be the cam timing.

Just take a pause, and then come back to it.

I’ve been there.

boyt911sc 06-09-2018 07:08 PM

Cam timing procedure.........
 
Quote:

Originally Posted by Tori (Post 10067770)
Putting my 3.2 back together after re-ring, and head rebuild.

At the point of installing rockers. Cam timing is done, and started with #1 exh. rocker so i could measure valve to piston clearance as per Waynes book.

Once #1 exh. rocker is installed, engine will not turn over as that piston starts hitting the valve. Engine rotated fine prior with just the #1, #4 intake rockers installed.

I've installed #4-5-6 exhaust rockers with no issues and engine rotates fine. I've measured the valve to piston clearance on 1-2-3 intakes, (4.25mm-4.75mm)

Where should i start looking ? I don't know what would cause this. I have to assume cam timing is not correct.




Tori,

How did you do the cam timing in the first place without the intake and exhaust rockers installed for #1 & #4 cylinders? Did you have the crankshaft set @ Z1 TDC for Cylinder #1? Keep us posted. Thanks.

Tony

Tori 06-09-2018 08:36 PM

Hi Tony, I had an old timer, retired Porsche mechanic help me do the timing. To my understanding, you only have to have the intake rockers in place. Is that incorrect ?

Ollies930 06-10-2018 01:54 PM

First thing I would do, is to double check that TDC actually lines up with your timing mark on your pulley. Use a piston stop if possible and remember not to spin it over too fast(do not slam into the piston stop).

Tori 06-10-2018 02:07 PM

Thanks, i will verify that, but the case was never split and AFAIK it never has been. Should still be the way ole' Ferdinand built her.

Flat6pac 06-10-2018 03:33 PM

Just look at the 930 marks on the cams. Z1 on pulley, both marks should be up or down depending on TDC for 1 or 4.
Are the cams on the correct side. The right cam has intake and exhaust lobes pretty much together so you can tell visually with out the rockers in
Bruce

Tori 06-10-2018 06:14 PM

Maybe this is where we went wrong. With #1 at TDC, this is the mark that lines up with the seam. I think we timed off the square notch to the left (white) - what is this other notch?http://forums.pelicanparts.com/uploa...1528679616.jpg

Flat6pac 06-10-2018 06:34 PM

Usually 35 degrees BTDC. Make sure the crank pulley pin is at 9 o’clock
Bruce

Tori 06-10-2018 06:49 PM

Pin looks to be more in the 10 o’clock position.
http://forums.pelicanparts.com/uploa...1528681728.jpg

Tori 06-10-2018 06:57 PM

Quote:

Originally Posted by Flat6pac (Post 10068698)
Just look at the 930 marks on the cams. Z1 on pulley, both marks should be up or down depending on TDC for 1 or 4.
Are the cams on the correct side. The right cam has intake and exhaust lobes pretty much together so you can tell visually with out the rockers in
Bruce

My pulley does not say Z1 (as far as i can see) I know the cams are correct, tagged each one as they came out. Plus i just verified the right side having the lobes close together.

Flat6pac 06-10-2018 07:15 PM

Crank needs to be with the pin locator at 9 o’clock The pulley will have the notch for TDC located near centerline. Mark pulley for TDC so there is no mistake
I use nail polish for all the marks with an extra large mark for TDC
Bruce

Tori 06-10-2018 07:41 PM

Just to make sure, are we talking about this as the pin?
http://forums.pelicanparts.com/uploa...1528684835.jpg

lrodri64 06-11-2018 03:45 AM

No, that is not the pin.
It is closer to the center covered by the bolt washer.

Mark Henry 06-11-2018 06:15 AM

Borrow a properly factory marked pulley and then index your pulley.
I index my pulleys with several timing marks by cutting notches (file or hacksaw), then I dab a bit of red paint in each notch.
Makes life much easier.

Tori 06-11-2018 06:26 AM

Ok, thanks. I will remove the bolt and confirm. I already have the current notches painted 3 different colors.

Flat6pac 06-11-2018 03:05 PM

That is the proper pulley for Carrera
Bruce

Neil Harvey 06-11-2018 10:40 PM

Just another good reason to use a degree when performing cam timing.

If you do use the simple common lift method, fit the crank pulley before you fit the cylinder heads. Use your dial indicator and holder, touch down to the Piston and find true TDC. Then mark the pulley.

That way you will not be confused about which notch is TDC.

rwest 06-12-2018 02:09 AM

Quote:

Originally Posted by Neil Harvey (Post 10070448)
Just another good reason to use a degree when performing cam timing.

If you do use the simple common lift method, fit the crank pulley before you fit the cylinder heads. Use your dial indicator and holder, touch down to the Piston and find true TDC. Then mark the pulley.

That way you will not be confused about which notch is TDC.

Great tip, thanks, I’m almost at that point and this will be a good way to make sure everything is perfect.

Tori 06-12-2018 02:45 PM

Borrowed the tools to run thru this again tonite. This time i'm going to do it by myself. I have the instructions printed out from this site, and i think i can pull it off with those, but does anyone know of a video showing the process on a 3.2 ? If i felt confident in doing it, i'd make one as i have not found one at this point.


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