rostig@fortune.UUCP (Grant Rostig) (11/12/85)
It appears that the old Toyota 18RC engines seem to ping badly
when they get old does anyone have any specialized information
on the problem? I have tried using 91 octange gas, *and* severely
retarding the timing. This still did not work.
The car does have 140K miles on it though.
--
Grant E. Rostig Fortune Systems, Redwood City, California
...!{ihnp4, ucbvax!hpda, sri-unix, harpo}!fortune!rostigahs@burl.UUCP (Spinks Albert H. ) (11/13/85)
> It appears that the old Toyota 18RC engines seem to ping badly > when they get old does anyone have any specialized information > on the problem? I have tried using 91 octange gas, *and* severely > retarding the timing. This still did not work. > > The car does have 140K miles on it though. > > -- > Grant E. Rostig Fortune Systems, Redwood City, California > ...!{ihnp4, ucbvax!hpda, sri-unix, harpo}!fortune!rostig *** REPLACE THIS LINE WITH YOUR MESSAGE *** Be very careful in how far you retard your timing. You can easily cause your exhaust valves to burn. As I picture it, retarding the spark causes the gas to burn later in the cycle. If this retarding is too far, the gas will still be burning when the exhaust value opens up. The hot, burning gas being forced out of the exhaust port at high pressure, etc. will get the value too hot--and presto--a repair bill. But this doesn't help on your pinging problem. Good luck on that. -- Albert H. Spinks
bcking@inmet.UUCP (11/16/85)
** head line ** If the head's never been off, one possibility is that there's a lot of carbon deposits built up in the combustion chambers. This is likely for an engine with this many miles, particularly if it burns a lot of oil. Two things can happen as a result of carbon buildup: 1. The deposits get so hot that they can ignite the charge before the plug has a chance to spark, thus causing detonation. 2. The chamber is so full of carbon that the compression ratio is actually increased due to decreased volume (I've only seen this condition for real in two-stroke motorcycle engines). R.M. Mottola Cyborg Corp. Newton, MA.
btl@mtunf.UUCP (Bernie Lee) (11/21/85)
> It appears that the old Toyota 18RC engines seem to ping badly > when they get old does anyone have any specialized information > on the problem? I have tried using 91 octange gas, *and* severely > retarding the timing. This still did not work. > > The car does have 140K miles on it though. > > -- > Grant E. Rostig Fortune Systems, Redwood City, California > ...!{ihnp4, ucbvax!hpda, sri-unix, harpo}!fortune!rostig *** REPLACE THIS LINE WITH YOUR MESSAGE *** Retarding your timimg too much can damage your engine. What model and year is your Toyoto. Does it have an air-pump?