996 3.4 Head Installed..Need clarification on cam timing...
#1
996 3.4 Head Installed..Need clarification on cam timing...
Hey Folks, I'm sure Ill be here often...I'm a tech at Highline/Exotic shop here in houston...My background is Audi, Lamborghini, Ferrari/Maser., BMW, MB, and now with my new shop....Porsche!
This is my first head-off for any porsche new or old and I'm running into an issue with the cam timing...
2001 996 3.4 5 Chain
I have the factory paper manual in PDF and all of the special alignment tools but here's where I'm running into an issue.
I can't find any clear indication of where it want's the crank in relation to the number 1 or number 4 hole when hanging the chain for the 4-6 head.
If you read the OE manual line by line, it says to rotate the crank 360 before installing the 4-6 head. Now if you started with the 1-3 head first, as the manual would have you do, then do your 360 that would put your number 4 hole at TDC compression and number 1 at TDC exhaust.
That's all fine and good, valve cover and chain installed, rotating the motor over by hand is gravy, Im even making compression....Well, 30psi is all i can get cranking it by hand....but the 'final alignment tool' will not install on the 4-6 head when the crank is at #4 TDC Compression. Now if I flip the motor to TDC on #1, it fits just fine but then my guidelines (Reluctor notch in relation to motor) for for cam position are out 180degrees according to the manual.
I've read the manual over and over and over, then hit pelican/google, and I'm getting conflicting information.
So to simplify my question...where in the hell does it want the crank when hanging the chain for 4-6, and where does it want the crank when doing the 'Fine Timing Adjustment'? Sorry, just loosing my patients a bit.
Makeshift Table-jack. My 'real' table-jack is holding the powertrain for a mercedes at the moment.
Any insite would be most helpful...I'm sure I'm missing something simple but there's so much data out there on these it's getting discombobulated in my head.
This is my first head-off for any porsche new or old and I'm running into an issue with the cam timing...
2001 996 3.4 5 Chain
I have the factory paper manual in PDF and all of the special alignment tools but here's where I'm running into an issue.
I can't find any clear indication of where it want's the crank in relation to the number 1 or number 4 hole when hanging the chain for the 4-6 head.
If you read the OE manual line by line, it says to rotate the crank 360 before installing the 4-6 head. Now if you started with the 1-3 head first, as the manual would have you do, then do your 360 that would put your number 4 hole at TDC compression and number 1 at TDC exhaust.
That's all fine and good, valve cover and chain installed, rotating the motor over by hand is gravy, Im even making compression....Well, 30psi is all i can get cranking it by hand....but the 'final alignment tool' will not install on the 4-6 head when the crank is at #4 TDC Compression. Now if I flip the motor to TDC on #1, it fits just fine but then my guidelines (Reluctor notch in relation to motor) for for cam position are out 180degrees according to the manual.
I've read the manual over and over and over, then hit pelican/google, and I'm getting conflicting information.
So to simplify my question...where in the hell does it want the crank when hanging the chain for 4-6, and where does it want the crank when doing the 'Fine Timing Adjustment'? Sorry, just loosing my patients a bit.
Makeshift Table-jack. My 'real' table-jack is holding the powertrain for a mercedes at the moment.
Any insite would be most helpful...I'm sure I'm missing something simple but there's so much data out there on these it's getting discombobulated in my head.
#2
Since you have the engine out, it would help to have the engine on a stand so you can rotate it. I think its much easier that way. Looks like you still have the trans on it though. Dont forget to secure the chain. You should have secured those guides against the chain while waiting. Cant see timing mark well enough in pic to see where you have it but assume you had it at #1 TDC for 1-3 side then rotated 360 to install 4-6 head? #4 Should be at firing position. Did you put it together then disassemble again? Can you post pics of cam bore hole and also flywheel side to show cam position? BTW, what repairs were you doing?
Last edited by KrazyK; 06-05-2014 at 01:23 AM.
#3
Rennlist Member
If the cam timing notches on the cam are properly aligned for bank #1-3 at TDC then you need to turn the engine over clockwise 360 degrees.
Bank #1 cam notches should now be perfectly upside down & 180 out. If this is the case you are ready to set cam timing for bank #2, cyl.# 4-6.
Bank #1 cam notches should now be perfectly upside down & 180 out. If this is the case you are ready to set cam timing for bank #2, cyl.# 4-6.
#4
I figured it out....The 'Key' on the special tool was reversed when it was assembled apparently....
I took the tool apart and flipped it 180 so now the notch is offset the correct way. This is why nothing was making sense. Now everything works as intended. I even started with 1-3, not that I needed to make any adjustments. rolled it 360, lined up my 4-6. Looks great....Ill have it in the car by the end of the day.
Here's my notch, facing down on 4-6 with the crank locked at tdc,
I took the tool apart and flipped it 180 so now the notch is offset the correct way. This is why nothing was making sense. Now everything works as intended. I even started with 1-3, not that I needed to make any adjustments. rolled it 360, lined up my 4-6. Looks great....Ill have it in the car by the end of the day.
Here's my notch, facing down on 4-6 with the crank locked at tdc,
#5
By chance did you buy this tool set off eBay? There's been previous posts about the eBay tool sets being 180 degrees off. I think they all come like that which is a huge error on their part.
#6
Former Vendor
"They" don't know because they never assemble engines. You get what you pay for with these tools.