Timing 4.6 2V positions

[CS2JZ]

Hello all,

I am new to the forums, but I have been lurking around for a while, ever since I got my 2003 Mustang GT. I bought it in non-running condition, and after a fuel pump and fuel filter change, she was running! So I replaced all fluids and put in new coils and plugs, started driving her around town. After about a week of driving, all of a sudden I started hearing this loud ticking noise and my oil pressure gauge kept dropping to zero and going back up. I was right next to my house anyway so I was able to get it in the drive way. I discovered the timing chain guides were completely destroyed and the LH timing tensioner had zero resistance, I know they should be somewhat hard to squeeze. So I ordered a new pump, and timing kit.

I looked through many forums and the best I could find was to set the crank with the hole facing straight down (6 o’clock) and the key is about 10 or 11. The cams are at their proper positions, I had the black links on the chains on the timing marks on the cams and crank. So after its all put back together, I try to crank it and it just will not run. It’ll start but runs very poorly and seems like its misfiring like crazy. I checked the compression and had zero pressure on a couple cylinders I checked on the drivers side. I take it all apart again and discover a few rocker arms had broken and fallen off, they are just laying there (on the driver side head). SO I obviously didn’t do that right.

I ordered a freshly rebuild an great condition set of heads from eBay, I’ve been talking the the seller a lot and he seems very knowledgeable on these cars. He’s been great help so far. But before I install these new heads and set the timing components all back up, I really need to make sure I get it right this time.

I’m learning there’s a TDC for power stroke and exhaust stroke, could I have gotten this wrong? I want to set the crank at the proper position and set the cams at their proper position before I install the heads.

 

[wmburns]

I’m learning there’s a TDC for power stroke and exhaust stroke, could I have gotten this wrong? I want to set the crank at the proper position and set the cams at their proper position before I install the heads.

FWIIW IF the motor were timed with the left and right cam banks exactly 180 degrees out of phase to each other what would happen?

• There would be no piston to valve contact (not the case here)
• The motor would pass a compression test
• The motor would run poorly (or not at all) and not make good power.

The fact there was PTV contact "proves" that the motor was not timed correctly (or skipped timing).

Also note that as far as the crank is concerned there is no difference between #1 TDC compression or exhaust. It's the position of the cam that makes the difference.

Bottom line. The modular 4.6 can be a difficult motor to time IF you decide to "do you own thing". That's why I would recommend using the Real Ford service manuals as the PRIMARY reference when working on modular motors. Resist the urge to rely on the forums as a primary source of knowledge. The cost of failure is pretty high for wrong information. Use the forums to "fill in" the gaps in your understanding.

If interested in getting a full copy of Ford service manuals with wiring diagrams for yourself I maybe able to help. PM if interested.

But. If looking for some insurance and a different way to time a 4.6 here's one. Remove all of the roller follows before installing the heads. Then all of the valves will be closed. It will not matter what order the work is done bolting on the heads as long as in the end, the motor is in correct time before the roller followers are re-installed.

Note, I have helped more than one person time their 4.6 that confused the left hand cam sensor "bump" for the timing mark (it's not).

I have also helped more than one person deal with the damage done after installing one chain and then turning the motor. NEVER turn the crank or cams with the roller follows in place and a chain removed.

Recommendation. ALWAYS take a picture of the crank and both cams when you think you are done. The picture should show the colored link on the chain as well as the dot on the crank gear. The picture should also show the colored link and the dot on the cam gear. ALWAYS turn the motor over by hand before putting the timing cover back on. Remember that the colored links will not line up after the motor is turned.

 

[CS2JZ]

Thank you for that information. I did find a Ford instruction PDF that has all the steps and where to put all the gears. Basically if I have everything set up just as those pictures show, and the motor spins freely and doesn't resist, it should be correct? I didn't use that bump you mentioned on the LH camshaft gear. It was pointing down.

So with the #1 cylinder at TDC, this is basically right at the end of the compression stroke and now the piston is on it's way down, which is the power stroke? So no valves should be opening up until the piston is on it's way back up, to push out exhaust. That's what I am seeing based on where the camshaft is for the #1 cylinder. At it's correct position for setting timing, both of it's valves are closed.

 

[wmburns]

I'm not sure that I understand your question. Have the new heads already been installed?

Just because the motor spins freely by hand does NOT necessarily guarantee there won't be PTV contact when the motor is running. Especially at higher RPM's. This is kind of thing that might happen if the timing is off by a tooth or two.

 

[CS2JZ]

It looks like I need to get ahold of a tool, # 303-448 that will make sure I'm at TDC, just putting the timing mark on the crank sprocket at 6 o'clock position doesn't seem to be exactly right.

The heads are not on the engine, they're actually still in the mail. I'm trying to get all my research done before they get here so I can do it right.

I appreciate the responses, I'm not exactly good at writing down the thoughts in my head.

This engine isn't as forgiving it seems as my old 7M-GTE motor from my Supra. I could rebuild those all day long and they'd run fine. But this engine is hard!

 

[wmburns]

It looks like I need to get ahold of a tool, # 303-448 that will make sure I'm at TDC, just putting the timing mark on the crank sprocket at 6 o'clock position doesn't seem to be exactly right.

^^NO! you do not need a tool to determine the exact TDC. In fact the 4.6 modular's "safe" setting is just shy of TDC with all pistons below deck. If the dot on the crank gear is "about" 6 O'clock it is "close enough". In fact of the motor's I have done, the dot is normally about 6:30 when the chain is installed. Remember that things will move when the tensioners are released.

The Ford specific tool 303-448 is useful to be certain that no one moves the crank away from the "safe" position. But the tool is by no means required.

The initial position of the cam dot (or marking line) is also an estimate.

What is VITAL is the correct number of chain links between the dots.

Don't over think this. The chains should have two colored links. One goes on the dot of the crank sprocket. The other goes on the marked cam sprocket. That's it! The motor is correctly timed. Take a picture.

Of course this assumes that you don't turn the motor prematurely. Or that the inside chain doesn't slip while installing the outside chain.

A tool that does make the job easier is a cam holding tool. This will keep the cams from turning when the chains are removed. But this tool is most often used to hold the cam in position when just replacing just the timing chain. Again if wanting to be certain there's no valve damage during the installation, remove all of the roller followers before installing the heads.

OTC 6477 Camshaft Holding Tool for Ford
Amazon product ASIN B000K2KZIUView: https://www.amazon.com/OTC-6477-Camshaft-Holding-Tool/dp/B000K2KZIU/ref=sr_1_4?s=automotive&ie=UTF8&qid=1529244724&sr=1-4&keywords=ford+4.6+cam+holding+tool


If you want even more proof that you did the job correctly, then perform a compression test. This has the added advantage of confirming the valves and rings actually seal.

Knowing what I know now, I'm not sure that if faced with needing to do a head replacement that I would do the work with the motor in the car. I would seriously consider removing the motor and doing the work on the bench. This has the added benefit that it's easy to check the oil pan for debris (a difficult job on the Mustang with the motor in the car). The access is soooooooo much easier on the stand.

Did you ever figure out exactly what you did wrong the first time?

 

[CS2JZ]

The first time I replaced the oil pump and all the timing components, I probably didn't exactly have the the black links directly under the timing mark on the crank sprocket. So after that is when I discovered the broken followers. So I replaced the followers with new ones and I did the timing as best as I could, the black links lined up on the cams and the crank sprocket. But I think I already had bent valves by this time and it would run very very poorly. I did a compression test on the drivers side head and it didn't have any pressure at all. That's when I decided to grab some rebuilt heads, as mine needed to be rebuilt now.

 

[CS2JZ]

The engine back together but when I crank it, it will not start. I noticed my RPM gauge isn't moving and I hooked up a scanner and it shows zero rpms the whole time. I checked for spark and I don't have any. I'm stumped right now. I double-checked the crank and cam position sensors. Before the rebuild I had RPM signal.

 

[wmburns]

Just wondering. Did you remember to put the crank trigger wheel in before installing the timing cover?

Almost certainly it won't start until the PCM receives a valid CKP (RPM) signal.

 

[CS2JZ]

I did. When I first took it apart I was like what the hell is this thing. But I found the issue. The wiring harness for the crank position sensor was twisted and shorted out. I couldn't see this because it was covered by that wire tubing. I fixed it and it fired right up! Revs strong too.

 

[wmburns]

Congrats!!!!

It might help others if you included some of your experiences doing the work and "lessons learned".

 

[CS2JZ]

Congrats!!!!


It might help others if you included some of your experiences doing the work and "lessons learned".

Well, some things to take away from this:

I removed stock headers attached to the heads, that oil dip stick is a nightmare.

I reinstalled BBK shorty headers with the new heads I received from ebay, forgot about the oil dipstick, but I eventually got it in through some bending and rebending.

I placed the crank at a safe position before I installed the heads, once I aligned the heads, I rotated the crank into position.

I verified timing was perfect with the tool I got from amazon, Ford wanted $225 for it, but I got it for $30 on Amazon. Probably wasn't necessary to have, but it gave me piece of mind, and now my engine is running strong!

I lubed all parts in the head with a can of engine restore before I installed the valve covers.

I made sure to unplug the fuel pump and let it crank for a little bit to get the oil pumped back through the block.

I wish I had labeled all of the bolts, where they came from, would've cut time down sifting through the pile and trial and error.
The picture is what was causing my engine to not start and not have an RPM signal. Once I fixed the connector, it fired right up.