Question1987 Toyota 4x4, standard cab, R22 engine, manual transmission.
I have just replaced the oil pump front seal which was leaking. After taking several days and much frustration I completed the job. When reassembling, I noticed that the large and small gears which make up the pump, have arrows stamped on them. I couldn't see where it made a difference how these arrows were lined up. After I finished and started the motor, I could hear a rattleing noise from the engine front. Before I go any further, could you please tell me where these arrows should be placed when the gears are set back in the housing, this may be the problem. I hope nothing was damaged. I only ran the engine for about a minute. Thank You for your assistance.
AnswerI have replaced many front oil pump seals and never paid any attention to these arrows, they are irrelevant, my best guess is that they were used for some assembly reason at the factory when new, again, whether they are lined up or not doesn't matter and it is not the cause of the rattling noise.
The noise is probably caused by a worn timing chain which needs oil pressure to pump up the tensioner to take up the wear of the chain, try running the engine a few minutes longer and see if the noise gets quieter as oil pressure builds up, if so, the timing chain may be worn and is making contact with the inside of the timing cover.
