Dashpot on the back of the head

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Highlander
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Joined: Wed Mar 12, 2008 8:22 am
Location: Nederland, CO

Dashpot on the back of the head

Post by Highlander »

The newest of our '85s (YoTrois) has a dashpot on the back of the head (which has been disabled). Yesterday I was adjusting the valves for the first time and noticed that it seems to actuate some rotary valves just above the intake runners in the head. The FSM has no reference to such. anybody know what the H*** it is? This terc pings no matter how far I retard the ignition timing- any thoughts as to whether these are related? This is the first time I've been into this engine, so I'm at a loss- at least its got a new timing belt now.
BTW this car originally came from the left coast- it still has a Sammamish High School parking permit on it- Any Left-coasters seen anything like this?
Last edited by Highlander on Mon Nov 24, 2008 4:40 pm, edited 1 time in total.
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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: Dashpot on the back of the head

Post by Petros »

I have never see it, but it sound like it might be a different type of EGR valve? When these are disabled there is a tentency to ping. But if timing does not affect the ping, it might also be something else.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
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