There are several reasons for replacing valve springs without removing head. These can include replacing valve seals, a new spring, breaking in your new cam without an inner valve spring installed, or to replace a broken valve spring.
Such a job could mean you need to take your vehicle to a machine shop to get the job done. However, you may be surprised to find that you can do the job in about an hour once you have all the right tools.
In our guide, you can learn more about what would be a complex job, yet with the aid of some air pressure and a valve spring tool, you can change valve springs at home. By the end, you’ll be changing valve springs in a shorter time than expected, and you can do this on your own or with little help. (Learn How Long Does It Take A Mini Fridge To Defrost)
How Can You Replace Valve Springs Without Removing Head?
You might need to replace the TDi valve seal without removing the head.
You can look up how to accomplish this, but a man from a machine shop devised a tool that performs it for you instead, saving you the trouble. Without removing the head, valve seals can be changed.
- Two things to consider are whether you pull away after the engine has been idling for some time and depressurize it before fastening the valve or valves springs. It’s bad news that these could fall to the bottom of the cylinder bore.
- The second reason is that installing the new springs takes time.
Additionally, without completely disassembling, you can use this tool to replace damaged valve springs, install high-performance springs, and remove and replace valve guide seals.
You can accomplish it quicker by replacing your magnet with a socket extension. Here, you place a rag under the valve and strike the extension or socket with a dead blow hammer, and you’ll see them pop out.
This is accomplished by applying air pressure to the cylinder ain via an adaptor and a compressor (via the spark plug hole on an air engine).
You can use a compression tester adapter to fill the cylinder with compressed air; it has a valve on it, so you don’t have to leave it hooked to the compressor because it only takes a few moments to do all the plugs valves.
Using an air compressor, air hose, and other necessary equipment will speed up replacing valve seals without removing the head cylinder.
New valve stem seals are required if the spring seats are being replaced.
First, you will need to obtain an attachment for your compressed air that can be threaded into the spark plug hole, and when used, it will maintain spring pressure as you work on your engine.
Can Only Valve Springs Be Swapped?
You can use a set of standard pliers if a valve seal remover is not available. You can ask around about changing your valve seals without removing the head, and everybody could tell you it is almost impossible.
They will not just come off with your hands, although it is possible. You can also use rope; if you use air and loose pressure, the valve can drop.
However, if you can roll the engine, so the piston is up and put the car in gear, then put the emergency brake on, that works with the air.
If your car is an auto, you put the air on the piston as it is forced down. Here, you can tap on the valve keepers and then pop the valve off its seat.
The valve spring seats are inserted first, then your valve seals. In a gas engine, this is accomplished by forcing air into the cylinder through the spark plug hole while utilizing an adaptor powered by a compressor.
You can use it to replace faulty valve springs, install high-performance springs, and remove and replace valve guide seals, all without entirely dismantling.
New valve stem seals are required if the spring seats are being replaced. (Learn How To Bury Extension Cord)
If Changing Spring Seats, You’ll Need New Valve Stem Seals.
You can use it for fixing damaged valve springs, installing high-performance springs, and replacing valve guide seals with no need to completely disassembling the motorcycle.
The valve seals in your car’s cylinder head deteriorate over time and become brittle. So I started looking around and came onto this guy who invented a tool that removes the valve seals without removing the heads.
Simply said, it’s one of the coolest tools you can find. Although, the valve or valves can drop to the bottom of the cylinder if you depressurize it before securing the springs.
Assemble The Spring, Retainer & Keeper
There are one or two alternatives to lifting the head to replace the valve spring.
Although it’s about 10 times more difficult than removing it on an engine stand, this procedure is probably the best way to remove valve springs while the engine is still in the car.
Make sure to compress the spring on one cylinder at a time using the required tools.
The V-Twin On-the-Engine Valve Spring Compressor is one of the most effective instruments for doing this.
Without completely disassembling the motorcycle, you can use it to replace faulty valve springs, install high-performance springs, and remove and replace valve guide seals.
All you need to do to get started is to remove the gas tank and rocker box assembly.
Here are the steps to replace broken valve springs on your bike:
- First, shift the transmission into gear with the front wheel locked and the rear wheel firmly planted on the work area.
- Disconnect the negative battery terminal and remove the rider’s seat from the vehicle.
- As directed by the manufacturer, remove the gas tank.
- Remove the rocker box to fully reveal the broken valve springs, including the lower rocker arm cover.
- Remove any additional brackets that would prevent the Valve Spring Compressor plate from being mounted.
- Install the cylinder head base of the valve spring compressor. The two threaded studs should point at the same angle as the valve stem when the big hole is placed over the valve spring.
- Tighten your fasteners in place.
- Using a typical shop air hose and compressor cylinder of 90 to 120 PSI, fill the cylinder through the spark plug hole using a valve tool. You do this to prevent the valve from falling.
- Compress the spring using the special tool and remove keepers and retainers using ordinary wrenches. Now You can change the valve spring or seals.
- Continue doing this until you change valve springs or seals on all the cylinders.
Use Rope to Replace Broken Valve Springs
Here is a bit more detail on the compressed air method, although some users do the same with rope as their spring compressor. (Learn How To Clean Brake Rotors Without Removing Wheel)
Keep your Valves in Place
Typically, the sparkplug for the cylinder you are working on is removed. Instead, an adaptor is threaded into the sparkplug hole, with a constant supply of compressed air passed through to the cylinder using an adaptor.
It would help if you kept everything in place to remove the valve springs without removing your cylinder head.
When changing a spring while the head is still attached to the motor, it is important to ensure that all of the valves in the bore you are working on are closed.
You can do this by using pressurized air fitting through the spark plug hole to keep the valves closed and in place while you remove the retainers and spring.
You can find there will be some air leaking past the piston rings; thus, you can see why you need a continuous supply of air to compress the springs, or they will drop.
Without a compressor and the right tool for the job, you can try this method to prevent the valves from entering the cylinder.
Simple Tools and Rope
All you need is a hammer, ratchet & socket set. Along with this, you need a valve spring compressor that has been designed to be used with the head installed.
A set of screwdrivers and a magnetic pickup can help make things easier.
Working Through the Sparkplug Hole
To access the cylinder, the sparkplug must be removed. Take caution, as the porcelain end of the sparkplug, is relatively brittle.
You can easily damage this if the socket is not kept straight on the plug (specialty sockets are available that minimize this possibility).
Rotate your Crankshaft
The piston must now be rotated in the cylinder’s direction’s base. Use a socket on the bolt that is facing the front balancer or pulley to do this manually.
Rotate onward to continue until the piston reaches or is close to BDC (Bottom Dead Center).
If the piston cannot be seen via the plug hole, insert a plastic straw or another flexible probe until it contacts the top of the piston, then turn the crankshaft. Where the piston is at its lowest position can be felt.
Make sure the length of your probe prevents it from falling into your cylinder.
Remove Your Rocker Arms
To ensure the valves are closed, remove the rocker arms unless you are doing this because of a broken valve spring.
Tap the valve spring retainer with the bottom of a hammer handle to loosen the seal between the retainer, compress the spring, remove the keepers, and you’re done.
Fill Space Above the Piston
Feed a rope composed of a material that won’t shed fibers through the sparkplug hole into the cylinder.
Continue feeding the rope into the cylinder, filling it as loosely as possible.
Rotate the Engine
Once more, manually turn the engine until you encounter resistance (the rope pressed between the piston and valve).
Keep some upward pressure on the valve if the valve spring is damaged and the valve does not entirely close to prevent the rope from becoming tangled between the valve and seat.
Valves Are Held in Place By Your Rope
When the valve spring is compressed, remove the keepers (a little magnetic pickup will help) and the spring using a valve spring compressor made for use with the head installed. Complete any required repairs. (Read Impact Sockets Vs Regular Sockets)
Removing Your Rope
Once the rope and valves are no longer under pressure, reverse the engine’s rotation and remove the rope retainer.