Can a hot exhaust valve cause a seat to loosen?
Can a hot exhaust valve cause a seat to loosen?
Anything that causes the exhaust valve to run hot may also cause the seat to loosen. The sound rule of thumb is to use .005˝ press fit when installing seats in cast iron heads, and .007˝ minimum in aluminum heads regardless of what type of valve seat inserts they are installing.
What happens when a valve seat comes out of a Ford?
Some of the earlier 1.9 and 2.0 Ford engines had what they called; powdered metal inserts that would actually break or just explode. When a valve seat comes out of it’s counterbore, it shatters or explodes into tiny pieces from impact.
Can a valve seat be finished after installation?
Seat Finishing After the seats have been installed, they can be finished as required. The guides must be reconditioned or replaced before doing this, however, because all seat work is done by centering off the guides. Seats should be as concentric as possible for a tight compression seal and proper valve cooling.
What happens when the valve seat comes out of the counter?
Some of the earlier 1.9 and 2.0 Ford engines had what they called; powdered metal inserts that would actually break or just explode. When a valve seat comes out of it’s counterbore, it shatters or explodes into tiny pieces from impact. As a result, those pieces from the valve seat may get lodged in the intake or exhaust manifolds.
Anything that causes the exhaust valve to run hot may also cause the seat to loosen. The sound rule of thumb is to use .005˝ press fit when installing seats in cast iron heads, and .007˝ minimum in aluminum heads regardless of what type of valve seat inserts they are installing.
When do you need to replace a valve seat?
For that reason, replacing valve seats is often necessary when reconditioning aluminum or cast iron cylinder heads. Another reason to replace a seat is if a valve has broken because the seat is not concentric with the guide. Misalignment between the seat and guide causes the valve stem to flex every time the valve closes.
Which is the best valve seat to install?
He says the 30000 Gold Series seats are easily machined and offer good wear and heat resistance for naturally aspirated and turbocharged engines. For high performance, heavy-duty and dry fuel applications he recommends the higher temperature 70000 Diamond Series inserts.
What happens if you have a leaky exhaust valve?
A leaky exhaust valve means the valve is not closing properly, failed compression stroke and a burnt valve. In some engine types, this burnt valve and the piston can hit bending the valve and causing major engine damage. If you suspected the thermostat, you should remove it and you can drive the car.
