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Cranks but no start -Misfire

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Diagnostic tools for testing and comparing  Camshaft Timing on Bank 1 vs. Bank 2

The whistle linked above does not work with the engine in the car while you work solo. It needs a 14mm spark plug adapter+1/4 barb fitting. I made one from  a spark plug Anti Fouler and a brass barb adapter + JB Weld. Think about how you will extract it if the hose spins on the barb ! Better is to use an extension/adapter tube.

See this thread for a link:

The Leakdown Tester works with a few tricks. If the hose for the leakdown tester x spark plug male threads is over 8" it will be tedious to fit. Mine was 18" .I made it work but 8- 12" would have been better. It all takes longer than you may think unless you have 2 long adapter hoses and run them into the passenger seat area.  Connect one hose to Cyl 1 and the other to Cyl 4. Now you can bounce back and forth with the leak down tester quickly. You need to rig the gauge via long air hoses to read while you are crunched up like a monkey behind the drivers seat to rotate the engine.


Caution = if your engine has good compression and you rotate it via the crankshaft nut (24 mm x 12 point) while under high air pressure it will really 'motor' just after TDC  ! Ideally you need high volume air and low pressure. Remember to 'set' calibrate your leakdown gauge before you start !

The other thing to remember is the cams rotate at 1/2 crank speed. So for any test you need to rotate the crankshaft 360 degrees X2 !

What you are looking for is  the TDC Compression/TDC Overlap situation shown in the color chart in a Post+link earlier in this Thread.

To identify a "180 degree out" mistake , what you need to do is this.

1. Set Bank 1 to TDC and lock in the basic timing position with the Bank 1 Intake Cam notch facing outward/toward the Cam Cover/away from the crankshaft. This is TDC Overllap for Cyl 1 (Bank 1) but TDC Compression for Cyl 4 (bank 2).

2. Measure and compare the Leakdown on Cyl 1 & 4 .

If your timing is "180 out' both readings will be roughly the same - very high leakage because both cylinders are at TDC overlap(or close to it).

3. If Cyl 1 shows high leakage (TDC Overlap = valves slightly off their seats) but Cyl 4 is TDC compression, it will show much,much lower leakage than Cyl 1. Don't worry if it isn't zero leakage(see later).

To get familiar with how the whole system works ,keep the air connected to CYL 1 and keep rotating the crankshaft to observe the change in leakdown rates. You will quickly feel when you are approaching TDC overlap(reduced leakage but fairly stiff to turn) with the next 360 degrees comes TDC compression -very stiff as you approach the TDC mark and it will whip the tool as you go past (power stroke).

Use the splendid color chart to turn the engine to TDC compression Cyl 1 . Then test Cyl 3 (mid of exhaust stroke) because it is easily accessible. It will have max leakage if you are doing the test correctly.

See Domiac's chart here -April 12, 2014 Where he has written "UP" , he means TDC Overlap. Where he writes TDC, he mean TDC Compression .That difference is the source of much confusion   :


If you think all this is excessive , tell me how else to test for TDC Compression vs TDC Overlap with the engine assembled and in the car. TDC is easy. It is that pesky Overlap vs Compression part that is the entire confusion ! The tests described would have reduced Domiacs epic thread to a one line answer.

Once my engine runs again, I post a simple one page cheat sheet so you can just check  both the Intake cam notch and the Exhaust Cam notches to confirm Overlap vs Compression at TDC. Way faster than what I've tediously described above ! But you need the 9612 puck to do that.

Baum/LN should send me one for the number of times I have plugged that tool.



Edited by Schnell Gelb
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Ahsai was correct. The timing was "out " on Bank 2.

Once I corrected the timing (camshafts r&r) it started immediately and ran well with no ticking Lifters  until............

That will be the next Thread !

I hope this Thread has been useful to gather in one place several hard to find resources .

Edited by Schnell Gelb
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  • 1 month later...

A small improvement to such a tool(I have the one Ahsai suggests) is to replace the cone with a barbed fitting that will thread into the spark plug hole. Just don't overtighten  it or you'll have an extraction/removal problem.This makes solo testing possible.

Better is to attach it to an extension tube that threads into the spark plug hole at one end and has a standard Amflo compressed air fitting at the other end. Innovative Products 7881


Even better is a kit like this and adapt it. But be sure you get the extension tube, not just a hose.


Then you can also do Leakdown and compression tests solo also.

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