Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Injection Timing Device: Notes
With the distributor injection pump stopped, a pre-loaded injection timing spring holds the injection timing piston in starting position. The pressure control valve, in conjunction with the spill orifice, keeps the fuel pressure in the pump's inside chamber proportional to the engine speed during operation of pump. See Fig 1.
From a certain speed the inside chamber pressure will be greater than the spring force and move the injection timing piston. The axial piston motion is transmitted by a slide and pin to the rotating roller ring. This changes the arrangement between cam and the roller ring so that the turning cam will be lifted to advanced timing by the rollers of the roller ring. This means that the position of the distributor piston in regards to rotary movement compared with the crankshaft or camshaft is displaced by a defined angle.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
Rather have a pro handle this?
A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.
No obligation. See pricing before you book.