I’m chasing compression and trying to eliminate ticking. Can you help me adjust my valves? EFI SBF roller block
I just replaced head gaskets, lifters, rocker arms, and pushrods on my 331 stroker SBF and I had a tick coming from the motor. So in an attempt to adjust the rockers/valves I am now chasing compression(I can't seem to line the cylinders up within 15% difference of each other). Most are around 130-140psi on a cold test but I have #1 at 70 and #5 at 185, I can't raise #1 or lower #5 for some reason. I need help getting this car to run properly and it's driving me crazy!! I need good compression with zero to minimal valvetrain noise….please help!! Can you get this valvetrain sor
Experienced mechanics share their insights in answering this question :
Hello. I would need to know more about the engine like what types of parts are being used. It simply sounds like the lifters were not bled off prior to setting the lash. If this was not done then that needs to be done prior to doing anything else. If it has been done then you may have some faulty lifters.
How to Identify and Fix Common car Problems ?
Our sources include academic articles, blog posts, and personal essays from experienced mechanics :
To adjust hydraulic lifters two fingers spin the pushrod as the lock nut is gently tightened. When resistance is felt on the pushrod, that`s zero lash. The adjuster is tightened to specs then the setscrew locks it in place. When changing valvetrain components always check rocker arm geometry.
Valve clearances are checked and adjusted when the crankshaft/piston of the cylinder you are adjusting are at top dead center on the compression stroke.
The effect of setting the valve lash too tight can result in the valve not fully closing on the seat. This will allow cylinder pressure to escape along with high-temperature combustion gases. It is possible then for the temperature of the valve head and valve seat to become so high that rapid burning can occur.
How Can You Quiet Your Car Engine? Once you verify the lifter ticking is not caused by a worn-out lifter or some other damaged part, the best thing to do is change the oil. Get rid of all the oil currently in the engine and flush it out before adding new oil.
Engine position for adjustment: To adjust the intake lifter/rocker, rotate the engine and watch for the exhaust lifter to be on the low portion of the cam (valve closed) and continue rotating the engine until the exhaust lifter just starts to rise (valve just starting to open), stop and adjust the intake.
To do that on a four-cylinder, eight-valve engine, use the rule of nine. Counting from the front of the engine if number eight valve is fully open, subtract eight from nine and the answer is one, so adjust the clearance on valve number one. If number six is closed, then adjust number three and so on.
To set the lifter preload, turn the engine in its normal direction of rotation until the exhaust lifter just starts to travel upwards. 2. Adjust the intake valve to zero lash and then turn the rocker arm adjustment nut 1/4 to 1 turn. This additional turning of the adjustment nut sets the lifter preload.
To adjust valve lash, loosen the locknut (10mm), and turn the tappet adjusting screw until the drag on the feeler gauge is correct. Then while holding the tappet adjusting screw with the screw driver, tighten the locknut, then recheck the clearance. Repeat the adjustment, if necessary. Reassemble and reseal.
If you notice that your engine is losing power when you start it or if you hear loud tapping or clicking sound when you start it, your valves may be out of adjustment. A rough idling time, especially before the car warms up, is another sign that your valves are out of adjustment.
Exhaust valves and air intake valves at the top of the cylinder can also get overheated, and leak gas or the valve seals can become too worn to seal the gas in properly. Either way, the result is often low compression. Several valve problems can lead to low compression.
Regurgitation (or insufficiency)
This is when your valve flaps are `leaky` and don`t close properly. This lets blood leak back through your valve and can make your heart work harder to circulate blood around your body.
Simply changing your oil can also get rid of the tapping sound, as over time an engine that is neglected of maintenance will begin to clog up its oil filters meaning that a build-up of grime can again lead to a lack of component lubrication.
Adding more oil will make the noise go away, but it won`t solve the underlying cause of the noisy engine – the oil leak.
In most cases, a faulty hydraulic lifter will simply need to be replaced. You might be able to get away with replacing a single bad hydraulic filter depending on the make and model of your vehicle.
Tick increases speed with increase of rpm – Motor Vehicle Maintenance & Repair Stack Exchange. Stack Overflow for Teams – Start collaborating and sharing organizational knowledge.
Globe valves are considered the industry standard for control valves because they are good at regulating flow, whereas ball valves are better for on/off control without pressure drop.
Remove the adjustment screw access cap located at the base of the cylinder on the flow control. Turn the cap counterclockwise to remove it. Use lock-jaw pliers if the cap is tight. Turn the adjustment screw in a counter-clockwise motion to increase the airflow to the cylinder.
The size of a burn can be quickly estimated by using the “rule of nines.” This method divides the body`s surface area into percentages. The front and back of the head and neck equal 9% of the body`s surface area. The front and back of each arm and hand equal 9% of the body`s surface area.
Rule of nine
With any given valve open, count what number valve that is from the front. Subtract that number from nine. Whatever number you`re left with is the valve you`re in position to set. So, with number 1 rocker opening its valve, you`ll be setting clearance on (9 minus 1), number 8 valve.
To set preload, merely tighten the adjuster nut another half-turn after zero lash. If you are setting the lash on a mechanical lifter camshaft, use the appropriate feeler gauge between the valve tip and the rocker arm and adjust the lash until there is a reasonable tug or pull on the feeler gauge.
If you add excessive preload, the engine will run rough at idle. So finding the exact point of zero lash is critical. It demands a deft feel when you can`t see the lifter. Hope this helps answer your question.
If there`s too little valve clearance, the valves won`t fully close, causing excessive heat, and the engine will lose power.
Major camshaft manufacturers recommend setting valves cold, to avoid erroneous adjustments on lifters that may be “pumped up” If you are setting valves on a fresh engine that has not been run, everything should be well lubricated before you begin.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
I’m chasing compression and trying to eliminate ticking. Can you help me adjust my valves? EFI SBF roller block
ANSWER : Hello. I would need to know more about the engine like what types of parts are being used. It simply sounds like the lifters were not bled off prior to setting the lash. If this was not done then that needs to be done prior to doing anything else. If it has been done then you may have some faulty lifters.
Please help me figure out where my PCV valve and PCV Hose is!!!
ANSWER : Hi there. The PCV valve is located on bank 1; the valve cover closest to the cabin. It is usually found under the intake plenum towards the passenger side of the vehicle. The hose will be attached; or loose. Please understand that a code retrieval and an internet search is not a proper diagnosis as there are several other possibilities that can cause the code to set. Some of the possible causes could be spark plugs, ignition coils, intake manifold leaks, intake plenum leaks, vacuum hose leaks, failing airflow meter, failing O2 sensors, exhaust manifold leaks, low fuel pressure, failing ECU, faulty wiring harness, failing injectors, etc… As you can see, the list of possibilities runs on and on. This is where the expertise and experience of a qualified technician with the proper diagnostic tools and procedures becomes invaluable. I strongly suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts and determine the exact cause of the code. Your Mechanic has several available technicians that can assist you with a check engine light inspection.
What’s wrong with my manual Jeep if I’m driving at 5th gear but it sounds like I’m driving at 3rd or 4th?
ANSWER : Since the car is still new, the vehicle should be taken back to the dealer to be checked under warranty. You may need a repair or replacement of the engine assembly. The engine may have an imbalance causing the problem. There is a technical bulletin that may pertain to this vehicle and call for engine replacement. The TSB is 09-008-16 and is dated June 16, 2016.
Engine shaking while in neutral and park
ANSWER : It’s possible you may have disturbed a vacuum hose while you were doing the job, check for that first. But I’m concerned about the valves because If you get the valve clearance too tight, it may develop a miss at idle. This is because the affected cylinder cannot get enough compression to fire at low engine speeds. I recommend you re-visit the valve adjustment right away, because driving with a valve adjusted too tight can quickly lead to a burnt valve. If you don’t find a problem in the valve adjustment, then it’s time to look at other possible causes. If you’d like to have another pair of eyes look at this to be sure, contact Your Mechanic to have a technician come to your home or office to check your valve adjustment and your misfire for you.
Intermittent ticking sound from front of engine
ANSWER : If the ticking sound seems to be dependent on temperature, I might suggest taking a look for an exhaust leak somewhere. Small exhaust leaks will normally begin when cold and diminish as the engine warms, but in my experience, I have seen exhaust manifolds and pipe connections that will respond in the opposite, like you are describing. I’m not sure if this is the case in your situation, but it is another credible place to look.
Car won’t start and immobilized light flashes
ANSWER : Try using an alternate key if you have it. If it starts easily with another key, then the first key is faulty and has to be replaced. If it behaves the same with any key, then it is possible it has a bad ignition switch or possibly a bad pcm – Power Control Module. Use the fuse box diagram and search for PCM fuses. There are two of them I believe. If either is blown, then that’s a sign there is either a bad connection or short at the pcm connector(s) or the pcm itself. If you would like, a certified technician from YourMechanic can come to your home or office, and make possible replacements to your ignition switch and inspect your wiring.
Ticking noise in engine does it need valve adjustment??
ANSWER : Hi there. The valves make a ticking noise as they wear, and in order to do any kind of valve adjustment you would need to have the valve clearance checked. If it needs adjustment, then the valve lash adjuster (also called a valve lifter) would need to be replaced. This is a major repair and depending on how may valves are in need of adjustment, your costs may rise close to or more than $1500. The labor for a valve adjustment in manual calls for 13.8 hours labor plus parts. If you are serious about the car, have a certified technician from YourMechanic conduct a pre-purchase inspection in order to have this corrected.
Are my steel lines broken on my radiator if they keep spinning when I’m trying to get them off? 2003 GMC Envoy
ANSWER : Hi – rather than broken oil cooler lines, I believe the problem is that the connections to the radiator for these lines are either compression nuts on the lines, or quick-connect fittings on the lines. In either case, the steel line can turn a bit – giving the impression the line is broken. Look more closely, and you should be able to see which of these two alternatives is implemented, and can removed them appropriately.
