Timing problem

[2Blew2B]

All,

I am working to get my mustang back on the road after a long winter.

Background: 200 Engine rebuilt with Yella Terra Full Roller Rocker lifters from mike + performance cam + 2BB Holley rebuilt + DuraSpark with control module


It all began with a hard to start problem at any temp

I reset the carb, got electric choke, and still had a hard time getting it started. Once started it idle ok but if you hit the gas you get hesitation. Runs rough in 3 or 4th if you are going too slowly.

I started playing around with the distributor. I advanced it and it started up with little to no problem but it was idle around 1000 rpm. I tried turning down idle screw but it had no effect on bring down the rpm. Although it ran great. No stumbling on takeoff or coming out of 2nd gear like before. Ran great in 3 and 4th going slow. I put timing light on it and found the timing was way off. The mark was set at rebuild it is now showing about inch past the 14 degree mark. I'm pointing the timing gun from the driver side and the make is past the 14 degree toward the passenger side.

As I said, at that setting it runs good. No hesitation but cant lower rpm below 1000.

Steve

 

[FalconSedanDelivery]

Was the Balancer checked for slipping ( a common deal on the Falcon 6 ) that would explain the problem

 

[2Blew2B]

Its was a new balencer

 

[MPGmustang]

did you time it with the vacuum to the dis un-plugged?

the vacuum changes timing, unplug it and retime, make sure it's at 12*-14* (where ever it's supposed to be) then add vacuum for the test drive and see if she pings.

the idle depends on your cam, I've found my cam 264/274 110 likes +850rpm, it's all trial and error.

remember to adjust the throttle position screw and the AF ratio screw for your idle.

 

[FalconSedanDelivery]

Its was a new balencer

Still Did You check it to verify that TDC is where its supposed to , Ive seen it before even new ones ,

 

[2Blew2B]

I did check with vacume advance disconnected. I have seen way to check for TDC but not sure of the best one.

Steve

 

[FalconSedanDelivery]

That last post tells me NO ( vacuum adv has nothing to do with checking TDC ) read up ! you need to verify

 

[2Blew2B]

I repainted my timing marks and spun her around until they were almost lined up with TDC and pulled the disto cap and sure enough it was at the contact point for #1. I got a new Holley 500 cfm...It works like a champ (See 350 vs. 500) so that has been ruled out. I think i will pull the plugs tomorrow but still confused. I can get her cranked it just takes a lot. i want to get in and just start it up.


Steve

 

[bubba22349]

I repainted my timing marks and spun her around until they were almost lined up with TDC and pulled the disto cap and sure enough it was at the contact point for #1. I think i will pull the plugs tomorrow but still confused.

Yeah but the other half of the puzzle is to find out were the position of the # 1 piston is when the damper timing mark is at TDC!

 

[2Blew2B]

All,

Another development. I have test drove 3 times with 500CFM and there are no problems with performance at all. It runs smooth. I did discover yesterday that after I warmed it up that I had a great chance of success cranking it up with holding the pedal all the way to the floor while cranking. I thought vapor lock but this also seems to be the case from a cold start as well. I'm not blowing off the timing marks but even if the balancer has slipped, I am advancing the distributor and having better success. Any thoughts

Steve

 

[CobraSix]

If you are advancing and getting better results, Think it lends more credence to the timing mark not properly aligned with TDC.

Starting it with the pedal down may just be helping correct improper timing which may be causing some flooding due to unburned fuel during the starting process. Could also indicate that the carb's needle valve is not seating properly and causing fuel to drain into the head while the car isn't running. This will cause two problems. Empty fuel bowl (meaning hard starts) and flooded cylinder head (meaning hard starts cleared by pedal to the floor).

But, you really need to determine the TDC mark is correct first. Honestly, it's not a huge deal if it's off, but you need to mark TDC somehow. What I did on an old block is just use a paint pen to mark TDC on the balance once I set it. Works great, especially with a timing light.

The way I determine TDC is simplistic, but works. Get a yard stick and a telescoping magnetic pick up wand. Pull #1 plug. You do need to determine the compression stroke. Two ways. #1 is to pull the VC off and watch the valve When both valves are closed on the upstroke, that's your compression stroke. The other way, is to put your thumb over the spark plug hole while you rotate the engine (by hand). When you feel pressure pushing your thumb, that's compression stroke.

Once you've determined that, get the piston within sight of the plug hole. Put the magnetic wand into the cylinder to rest on the piston. Extend the other side of the wand out. Place the yardstick perpendicular to the block towards the end of the wand. The further out you can put it, the more accurate the results of the process will be. When I do this, I use a 2x4 across the top of the engine to inside of the fender lip. Using a wax pen, I mark the spot the 2x4 is on the fender. I clamp the yard stick to the 2x4. This allows me to do this solo and with consistent results.

Now slowly rotate the crank in the normal rotation direction until the wand appears to change direction. Don't worry about getting it dead on the direction change, just when it appears to change direction. Now, keep rotating the engine until the wand is about 1" (or pick a value, doesn't really matter) below the spot you saw the direction change on the yard stick. Mark this spot and do NOT move the yardstick or wand. Now, rotate in the opposite direction (counting the number of rotations) until the wand is on the same marked spot on the yardstick. When I do the rotation, I try to do it in 45* increments as best I can. Say it took 4 45* rotations (just pulling it out of thin air) Now, go back the normal rotation 4 rotations and you should be back at the same mark. If so, now go backwards half the rotations (so 2 for this example) and you will be at TDC. Check your timing mark. If it's not at 0* on the indicator, then use a paint pen to mark the balance where the indicator's 0* mark is located.

One of these days (likely when I put my new dizzy back in) I'll take some pictures of this process and post them.

 

[2Blew2B]

All,

Updates + one more problem

Ok I fur sure made sure it was TDC. I could see the #1 piston come all the way up and it blew out the napkin I put in #1 spark plug hole. The mark was dead on. Things I did today. I bought another Accel Super Stock coil. I had the same one before but it was several years old. I replaced the spark plugs with Acdelco 46 gapped it at .50. I put new spark plug wires and reset timing to 10 degree and she has started up in every situation (cold, hot, hot after sitting 10 min, and on the cool down around 160) so yea

The strange part: as part of my testing I cranked up and pulled each spark plug wire off one at a time and the first 3 (starting at #1) made the engine idle down a great bit. The next 3 seem to have no effect. I did put my timing light on each wire and got a strobe on each one. ??? Is that normal??

She drives well with no stuttering or power loss. The idle is the only issue now. It not really smooth but not horrible rough?? It idles at 0900 - 1000.

Any ideas?

 

[bubba22349]

This is not normal, time for you to do a compression test! All cyl.'s need to be close in compression within 10 psi is real good up to 15 or so will work okay, much more than 20 and it won't idel smooth

 

[CobraSix]

Well, If you put the inductive sensor on each wire, yes, you will get a strobe flash for each cylinder. However, it would not show the balancer mark at TDC, except for #6 (I can never remember the firing order, which ever one is 180* out of #1).

But if your question was about the idle change while pulling wires, then no, that's not normal. The engine will usually droop a little for each pull.

Check a couple of things. Check your spark. Could be you have weak spark on those cylinders so pulling the wires won't have a big impact. Pull the plugs and slowly move the wire back towards the plug. See how far away the spark jumps the distance. Compare that distance to the others. If the spark is weaker, replace the wires.

I would agree with bubba, sounds like you may need a compression check, or double check your valve adjustment. Make sure those valves are seating.

On the off chance, verify your wire order on the dizzy. Make sure you have them correct. Not that I've ever messed that up. No, not me...

 

[2Blew2B]

Cobra Six,

I did make sure the #1 is TDC...no question. My timing is now in the normal range...not sure what was going on there. It did the same thing with the old wires ad it did with the new ones I just made, I swapped wires on #3 and 4 to check the wire and it checked good. I will try the spark trick but I am leaning toward a valve adjustment. I purchased the Yella Terra Full Roller set from mike and I think maybe it needs to be adjusted on those three. I am going to see my machine shop guy next week. I also going to spray some carb cleanner to make sure there are no Vac leakes and do a compression test.

 

[2Blew2B]

All,

I did of a lot of testing today. I did a conpression test and got around 200 psi on all cyclnders. one was 195 and on was 203, so all about the same. I tested each spark plug wire with a bolt to engin black and got a spark on each one. I put each matching spark plug in the wire and tested those as well. All good. I even moved my coil to the fender well to keep the heat down. she cranks up great just fine now and the idel is pretty good just not as smooth as i think it should be. Could it be the agressive cam i have in it?

Steve

 

[MPGmustang]

all I saw was "performance cam" about your cam what cam do you have?

like I mentioned, my 264/274 110* cam idles rough, even sounds like one of them bent-8's with an agressive cam.

I can't get mine to idle smooth unless I aim for 800rpm, with AC it sits 500-550 but it's rough and shakes the whole car, sometimes I think I hear bolts falling off the car when this happens... so I turn off the ac @ idle... lol

 

[2Blew2B]

All,
Here is the deal now. I crank it up and it does idle rough but if i push in on the clutch it smoths out...any ideas

Steve

 

[redxm]

Oil too thick in the gearbox, tight bearings...

 

[2Blew2B]

Wow....I would have never considered that but to be honest it makes a lot of sense. I have not changed the oil since the rebuild and my engine guy had me run 20w50 VR1 with zinc for the cam break-in. I haven't put a lot of miles on the car but it has been a while since the rebuild. Additionally, I rebuilt the Toploader 4 speed and used that bearing goop and never drained it out. I would be so ecstatic if that was the issue. I will change both this weekend and report back.

Question though: what type and grade is everyone running? I guess I need thinner oil?

Steve