Hradec

Hi,

I am rebuilding my engine and getting close to finishing. I have a habit of second guessing myself especially when it comes to cam timing. I have been following the proceedure in the bently and 101 projects books. I started with 4-6 bank, pnned the crank at 1 tdc, installed cams as pictured, cam honlding tool in place no problem.

I continued to bank 1-3, pinned the crank dropped the cams in, locked the cams, everything just went too easy.

cam holding tool fits in both 1-3 and 4-6 bank with crank in same 1tdc position.

Was I suppose to turn the crank 360degrees after completeing installation of 4-6 cams before initiating 1-3 cam installation.

I am recalling when I initially took engine apart the cam plate did not fit in both positions with crank pinned at tdc, maybe chain was stretched/worn, or in fact was I was suppose to turn engine 360degrees before initiating installation of cams in other bank?

There is such little info on the 3 chain engines. neither of my printed sources mention turning crank 360 degrees

cant go any firther until I resolve this

Thanks

Glenn
2003 C4S M96 03
3.6 LN nickies

Ahsai

That is correct. Otherwise you'll be in for a surprise when you start the engine - only one bank will fire.

This should never happen -> "cam holding tool fits in both 1-3 and 4-6 bank with crank in same 1tdc position."

Hradec

I was suppose to turn the crank 360 degrees after 4-6 cams were completely installed and before 1-3 were installed? none of the printed material says to do this

Ahsai

Correct.

Actually it was printed in one of the older versions (3.4L engine) but in the later versions I couldn't find that. Jake Raby had mentioned multiple times about this easy mistake.

Hradec

Thanks so much for this info, glad I second guessed myself. To correct this, I need to lock the cams 4-6 and crank to tdc, disassemble 1-3 side, remove cam lock from 4-6,
turn engine 360 dgrees clockwise,
Pin crank at "tdc" line up cams 1-3, lock cams, bolt the sprockets

I turned engine gently through by hand no damage done

Ahsai

You can disassemble either side. No damage was done even with your current setup because each cylinder still have the correct 4 strokes. Just that bank 1 and bank 2 are 360 degree out-of-phase so instead of the normal one compressing cylinder every 120 degrees, you have two compressing cylinders simultaneously every 240 degrees.

Hradec

Actually it does matter, doesn't it ?

Hradec

If I reassemble the wrong side it will be on the exhaust stroke when the Piston is going up on number one, instead of compression?

Ahsai

Timing for a bank is correct if you can fit the cam timing tool with engine pinned at TDC #1. For the timing between the banks to be correct, you just need to add a 360 degree offset between them so only one bank will fit the tool at any time.

Hradec

Doesn't the reference for fuel and ignition timing need to be correct, does that come off of the cams or the crank

Youri Ko

Just undo that side and rotate the crank 360 - everything will be fine

Flat6 Innovations

Unless the crank is rotated CW 1 full 360* rotation between timing each bank. If this doesn't occur you'll end up with both banks timed the same, which will be an issue. One bank should be @ TDC at the exact same time the opposite bank is @ TDC overlap

Of course, we spend 6 hours on this in my hands on class, which is where Ahsai learned about it :-)

Ahsai

Yeah, in fact we learned the timing procedures for both the 3-chain and 5-chain engines.

It makes your head spin

Hradec

Thanks for all the info unfortunately the published material I was armed with leave bout the important step of rotating the crank 360 after the first bank is timed
Glenn

AWDGuy

I will be doing this as soon as the rest of my parts come in. Any other tips or tricks you can provide that will help with this?