Please help with camshaft synchronizer!!

[Tsestak45]

So I've read about 100 times that when replacing the camshaft synchronizer use the "special" alignment tool and all that. That's great and all IF your old one was assumed to be placed correctly. What I can't find anywhere is an article explaining from scratch. Once you have the engine at TDC where does the flag on the top of the synchro need to be in regards to the "opening" on the top that it spins around, and also does that angle you put it in at really matter as long as that flag is in correct placement with regard to the camshaft position sensor? Been struggling with this for like 3 weeks so any help would be greatly appreciated. Also if I have no CEL does that mean my timing isn't off at all. I have slightly low vacuum (16-18) and surging after warm up?

 

[fastpakr]

This video explains it as well as anything I've seen:

 

[RonD]

Needs to be at #1 TDC compression stroke, there are two #1 TDCs on a 4-stroke engine, compression and exhaust strokes

Its the same as timing a distributor, the "rotor" needs to be timed to #1 compression stroke TDC

Cam synchro also has a "rotor" that needs to be timed to #1 compression stroke TDC

Distributor has a Cap that only fits onto the housing one way
The Cam sensor only fits onto the housing one way

The housing on either can be turned to match up "rotor" to #1 compression stroke TDC, on the Cap or Cam sensor
But you have to install the housing so "rotor" is within a few degrees of correct #1 TDC Compression stroke or you won't be able to turn the housing far enough to get it in correct position
This is the "gross" alignment
Once housing is lowered down to engage the cam gear gross alignment is done
Then you can fine tune alignment

The tool for Cam sensor makes it much easier to fine tune
The computer does have leeway to self adjust cam sensor timing based on Crank Sensor timing, which is why you don't need to use a Timing Light like with a distributor
Computer just needs to know which stroke #1 is on, compression or exhaust, which can't be known with crank sensor pulse, so cam sensor is used to set injector opening time to coincide with intake valve opening so less wasted fuel, and also helps fine tune spark timing


Heads up
A distributor or Cam synchro also drives the oil pump shaft, this usually has a Hex drive
So when you lower the housing down it may not drop all the way down, this is because the oil pump shaft is not aligned with the housings drive
If crank is at #1 TDC mark then use a socket to manually rotate crank 90deg left and then right of TDC mark
The Housing should drop down on its own once shaft is aligned
Then turn crank back to #1 TDC to finish gross alignment and fine tuning

 

[Tsestak45]

Thanks both of you. Some of that info I had already known but it helps me explain my next question. So when I'm at TDC the missing tooth on my harmonic balancer is inline with the triangular mark on my water pump cover correct? Because I have also heard 5 teeth before it? Also when at TDC my "flag" inside that the tool holds still is at 0° with the center line. I would imagine that as long as the sensor is screwed on perfectly inline with the "flag", like when he uses the tool in the video, the that should be all the matters I would think? Not as to whether or not it's at 15° or 0° as long as the sensor and "flag" are inline when the engine starts up from TDC?

 

[Tsestak45]

Oh also, if my timing is off wouldn't I have a CEL or is there some gray area between?

 

[Tsestak45]

When I'm at TDC this is how mine looks on my truck but that video is saying it needs to be more where the red line is correct!?

 

[Tsestak45]

No I'm 99% certain that my camshaft synchronizer is correct. So what else can explain a low vacuum (usually around 16 or 17) and surging after truck warms up and then throttle is hit? Usually it idles fine until the first time any throttle is given. It never really comes back to idle and surges progressively to stall. IAC is new and tested. Have had this problem since my brand new remanufactured (Power train Products) engine was put in. Did the first one myself and it blew a rod so the second time I had a mechanic do it because I didn't have a garage anymore and it hasn't run correct ONCE since I've gotten it back. He hadn't put a wrench on a single bolt hand to God, just hand tightened everything. I think because he knew I was mechanically inclined (though I in no way would consider myself a mechanic) and he could do less work. So now I've been going over literally everything he touched and can't track down this last problem. This has been a 1 1/2 year process and I love my truck and want to drive it again soooooo bad. Hoping to one day makeitrunlike it did after the factory. I've replaced like 80% of the stuff under the hood but I'm so close to giving up on it because it is extremely draining. Sorry for the rant, no therapist, send me a bill!

 

[broncc]

-- message deleted I thought this was the 4.0 not the 3.0 forum oops --

 

[RonD]

TDC Mark is a line on the crank pulley(0 deg) and there is a pointer on front cover, looks like this: https://www.explorerforum.com/forums/attachments/4_0-synchro-4-jpg.168693/

You were describing the Crank sensor and its tone wheel(missing tooth) that's behind the pulley and as seen in picture missing tooth is NOT aligned with crank sensor at TDC

But there are still TWO TDCs you have to be on the correct one, #1 TDC compression stroke

Cam sensor timing shouldn't cause low vacuum

 

[Tsestak45]

Thank you. Yes I noticed my mistake with the mark last night and corrected it to the right one. Man what a difference on start up! Barely even got the key completely turned and it fired up! Not since I got it has it started that fast. Unfortunately still starts at about 17-18 in and settled at like 15-16 in. Keep getting "O2 heater circuit bank 1 sensor 2" and it's the second brand new sensor I have tried. Bad wiring maybe? Also I e read exhaust and emissions can lower vacuum but I find it hard to believe it could lower if that much? Thank you all for your help and knowledge as well. The last 2 years I've pretty much learned everything from reading these forums but finally got to the point I had to post something. I was afraid it would take forever to get a response but you guys are all super quick. I appreciate it

 

[RonD]

O2 Heater circuit code means one of the 2 heater wires on that O2 sensor is broken/not connected

All O2 heaters are powered by fuse 13 in engine bay fuse box, it also powers other things
Each O2 heater has its own Ground wire to computer

Fuse 13--------light blue/orange stripe wire-------------O2 Heater---------------computer

When you turn on the key, fuse 13 gets 12v(1998)
The 12v goes to the O2 heater and then OUT of the heater to the computer, if computer "sees" the 12v then it grounds that one heater to get it to warm up that one O2
If no 12v then it sets the "O2 Heater Circuit" code

All 2, 3, or 4 O2s share the light blue/orange wire as the 12v source(1998)
Unplug the 4 wire connector for that one O2 sensor and test the light blue/orange wire for 12v with key on
If you have 12v then that wire is OK, if not then wire is bad
Other wire is harder to test but IS the issue, its wire color depends on position of O2 sensor
What is the exact code shown, that will tell you wire color to computer?

O2 sensor wires often get too near exhaust pipes so can melt/break
Or in the case of upstream O2 wires the wires get pinched between engine and bellhousing after engine or transmission work, so get damaged



Yes clogged exhaust will lower vacuum
Easy test for that is to use the vacuum gauge
engine idling
Vacuum steady at say 16"
"Blip" the throttle, quickly open it all the way and then let it snap closed
Vacuum should drop to 0" then pop back up quickly to above 16" then settle back down to 16"
If vacuum doesn't drop to 0" and only slowly comes back to 16" then could be clogged exhaust

Then do this test
Raise RPMs to 2,000(approx.) and hold
Watch vacuum gauge, if its slowly dropping you have clogged exhaust

Pull out both upstream O2s
Start engine, its loud, lol
Test vacuum, if higher then looks like clogged exhaust is the issue
Repeat above tests to confirm better vacuum now

Engine is a self powered Air Pump
If you limit Air IN or Air OUT then pump can't run efficiently

 

[Eddo Rogue]

One of the more difficult things my swap was getting the oil pump drive to stay centered so the synchro would drop in over it. I leveled the truck in both directions and then dabbed some grease around it with one of those wooden bbq skewer sticks. Still took some finesse and a few tries, but I got it.

 

[RonD]

I thought there was a slide on thin "washer" that kept the oil pump drive centered in the hole, but might have been a different engine

 

[alwaysFlOoReD]

I thought there was a slide on thin "washer" that kept the oil pump drive centered in the hole, but might have been a different engine

There is on a 460. I couldnt figure out what it was for and whether it needed to be up or down... I ended up losing it somewhere in the oilpan. I was still able to button up the motor.

 

[dvdswan]

There is on a 460. I couldnt figure out what it was for and whether it needed to be up or down... I ended up losing it somewhere in the oilpan. I was still able to button up the motor.