hand crank and no compression


whitebroncoii87

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Hi, I put my engine back after changing out head gaskets and lifters. It won't start. I was trying to confirm it's not a firing order issue so removed all spark plugs and hand cranked it to find the compression stroke on 1st piston and then to use that to rearrange my plug wires. I hooked up a compression gauge from autozone into the 1 spark plug port and then 2 other ones and got no reading any of them - I guess no air entered the gauge.

1) Is it normal since it's a hand crank? If normal how do I find compression stroke? I watched the rotor when harmonic balancer points to tdc and it's at roughly 12'o clock and 6'o clock (one being compression the other exhaust, how do I know which is which?).

2) If not normal, what are some possible problems? Thank you very much!
 
What engine are you working on?
BII 2.9l?

You should be able to put a spark plug, or compression gauge, into one cylinder's spark plug hole, and assuming other spark plugs are removed, feel when compression strokes starts on that cylinder by resistance when manually rotating the crank, clockwise(for most engines), if you go counter clockwise there would be no compression stroke.

There is only 1 TDC mark on crank, that is when #1 piston is at TDC, top dead center, the Valve Timing(cam position) decides if that is #1 TDC compression stroke or #1 TDC Exhaust stroke, but TDC mark will be at the same position for both, there is no 12:00/6:00 positions.
4-stroke engine means each complete cycle of a cylinder requires 4 strokes of the piston, intake(down stroke), compression(up stroke), one full rotation of crank has now occurred, power(down stroke), exhaust(up stroke), 2nd full rotation of crank is complete, cylinder has completed one cycle.

Cam only rotates one full turn for each 4 strokes, if you look at a time belt or timing chain you will see the crank gear will have 15 teeth and cam gear 30, or 10 teeth and 20, or 20 teeth and 40, so crank turns 2 times for 1 full cam rotation.

The rotor in distributor is running off the cam, and distributor must be timed for the cam position not crank position, BUT(big but).......
Assuming timing chain has not been changed/altered you can use the TDC mark to time distributor.
As you have surmised you do need to find when compression stroke for #1 is occurring, OR, you can just time it one way and if it doesn't start change it, it is a 50/50 shot and won't hurt anything.
Put Crank so TDC mark is at 0 deg
Pull out distributor and put it back in so rotor will be pointed at #1 spark plug wire, rotor will move as you lower distributor, so allow for that movement
Snug up distributor
Follow this firing order for 2.9l(half way down the page): http://www.therangerstation.com/tech_library/2_9_Page.shtml

Try to start engine, if it fires up, you guessed right, remove SPOUT connector and fine tune spark timing.
If it doesn't start, pull off distributor cap and mark the exact location of the rotor, you can "bump" starter motor so rotor is point at something.
Now pull out distributor and rotate rotor 180deg, from where it was before, opposite direction exactly.
Snug it up, put on cap and it will start now.
 
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yes, 2.9l bii. i meant the rotor points to 12 o'clock and then 6'o clock when the timing cover passes tdc.
 
I would not really expect to see any action on a compression tester if you are turning the engine by hand.
 
I would not really expect to see any action on a compression tester if you are turning the engine by hand.

Exactly...or very little as in you can feel a slight pressure against your thumb...
 
yes, 2.9l bii. i meant the rotor points to 12 o'clock and then 6'o clock when the timing cover passes tdc.

Yes, that would be correct, in that distributor rotor(and Cam) rotate at 1/2 the speed of the crank, so if TDC was when rotor was at 12:00 then next time TDC came around rotor would be at 6:00.
Or 9:00-3:00, 11:00-5:00.

If you don't want to pull out the distributor, then remove spark plug wires
Put #1 wire at 12:00 on cap, #4 wire at 2:00, #2 wire at 4:00, #5 wire at 6:00, #3 wire at 8:00, #6 wire at 10:00

2.9l Firing Order 1-4-2-5-3-6

Try to start, if it doesn't start then pull off the spark plug wires and start again BUT............start with #1 and 6:00, #4 at 8:00, #2 at 10:00, ect....

Distributor cap doesn't have a starting place for firing order, even if it is labelled, although if there is a label it is just easier to get everything lined up for using that, but it certainly isn't required.


You would certainly feel resistance when turning crank manually with compression gauge installed, when you were on the compression stroke of the cylinder with gauge, assuming no spark plugs in other cylinders
 
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I did that with #1 wire over 6:00 and then 12:00 no start. that's when I pulled the spark plugs out and stuck compression gauge in the #1 spark plug hole and got no reading. I removed the main coil wire and unplugged fuel pump relay and turned the key with gauge remain in #1. Still no movement on the gauge needle. Either gauge is broken or something is amuck..
 
remove 5 spark plugs, so only one is remaining
turn over engine with starter motor, should go fast then "wump", go fast then "wump".
Wump is the compression stroke of the cylinder with spark plug.

no Wump means lifters or rockers are not right, unless you removed timing cover and messed with the timing chain
 
no, i didn't mess with timing cover. I'll go check tomorrow with #1 spark plug in and rest out. I changed out the lifters and readjusted the lashes so that could be problematic. Now, will I be able to see the rocker arms bob up and down when I hand crank over each piston? (How would I test my lifters and lash adjustments are correct?)
 
If you have access to a squeaky doggie toy...

Remove the whistle in it and find out direction of air flow in it.

Get a length of rubber hose and put one end in spark plug hole, other end will have the whistle.

Turn engine by hand with all plugs removed and coil disabled.

When whistle makes sound that cylinder is on compression stroke.

Ray
 
no, i didn't mess with timing cover. I'll go check tomorrow with #1 spark plug in and rest out. I changed out the lifters and readjusted the lashes so that could be problematic. Now, will I be able to see the rocker arms bob up and down when I hand crank over each piston? (How would I test my lifters and lash adjustments are correct?)

You may have over tightened rockers so valves are not closing long enough or under tighten so they are not opening enough.

2.9l should have hydraulic lifters, which means there is no need to set valve lash as you would for solid lifters.
You can do it, but there is no real need to do it.

With valve covers off and spark plugs out watch #1 intake valve(intake valve lines up with intake port on the head, exhaust valve lines up with exhaust port)
Turn crank clock wise until you see #1 intake valve start to open, continue turning crank and #1 intake valve will close.
After #1 intake valve closes continue turning crank clockwise to 0deg TDC
You are now at TDC for #1 when spark plug will fire(so you can also set up distributor at this time.)
Loosen #1 intake and exhaust rocker nuts until rockers are loose
Tighten nuts until there is 0 lash, rocker is against valve and push rod with no gap.
Now tighten nut 1 full turn, 360deg, then tighten another 1/2 turn, 180deg
What you are doing is pushing down push rod to the center travel of the hydraulic lifter, when engine starts oil pressure will pump up lifter so valve open/close timing will be correct.
With solid lifters you need to adjust valve lash, and you need to adjust it over and over as parts wear, hydraulic lifters shouldn't need any adjustments once they are setup.

So #1 intake and exhaust valves are done, time to do the next cylinder.
Use the Firing Order 1-4-2-5-3-6
We know the crank turns 2 full rotations(360 x 2 = 720deg) for 1 complete cycle, and there are 6 cylinders, so...............
A cylinder will be at its TDC(firing) every 120deg, 1/3 turn of the crank, clockwise.
Rotate crank 1/3 of a turn, close is fine since intake and exhaust valves have been closed awhile on the next cylinder.
Next cylinder would be.....#4 according to firing order, adjust rockers same as above.
Rotate crank another 1/3 turn, time for #2
Rotate crank another 1/3 turn, should be back on TDC mark :) and time for #5......
1/3 turn #3
1/3 turn #6

Make sure you tighten each rocker nut the same, 0 lash then 1.5 turns more.
Some use 1.75 turns, driver's choice, but they all need to be the same
 
ok 1.5 turns after 0 lash, got it. I did 0.5 turn.. I will go redo that. Thank you so much for the detailed explaination.

Also, do I need to bleed out these new lifters? I didn't. (Something like sticking a needle/paper clip into a hole in the lifter?)
 
Generally with new lifters you just soak them in oil for a while before install. It helps to compress them before dropping them in the oil.

You can also run the oil pump drive shaft with a drill and a 1/4" socket for a bit to prime the system. Should get the oil to the lifters a bit faster after starting.
 
what is the function of soaking them in oil? I dunked one end in oil in my egg crate for about 5 seconds then flipped it around to dunk the other end. So I achieved coating the entire lifter well in oil but not sure how much got inside. Is that crucial?

Where do I access the oil pump drive shaft? Thank you!
 
The point of soaking the lifters is the same as letting your dollar-store squirt gun. Air out, fluid in.

Oil pump rod is accessed through the distributor hole.
 

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