 Gasoline - 90 Octane, Ethanol Free (89), or additives, How to reduce valve knock |
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| dcecc1968 |
 Feb 6 2019, 07:46 AM
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Member  Group: Members Posts: 255 Joined: 31-December 12 From: Concord, NC Member No.: 15,313 Region Association: South East States  |
We are having some Spring weather this week in Charlotte, NC (and no rain!) so I've been driving the 914 and noticed that after about 20 minutes of driving, the valves intermittently knock from "normal" to very loud for no apparent rhyme or reason.
Outside of the obvious that it may be time for a valve adjustment, I wondered what Gasoline grade folks are using. What Petro are you using in your 914? |
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| dcecc1968 |
Feb 6 2019, 02:17 PM
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Member Group: Members Posts: 255 Joined: 31-December 12 From: Concord, NC Member No.: 15,313 Region Association: South East States |
Thanks for your suggestions. I will definitely check the timing on the engine. Little is known about the engine historically other than I've been driving it for 4 years. Was told it was a 1.8L when purchased, but the stamped engine code says it should be a 1.7L.
The engine knock sometimes is more like a rattle/clatter. I'm running dual weber carbs IDF40's with the air mixture screws @ 1.5 turns out. I didn't think of the engine running lean... that may be part of the problem. |
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Posts in this topic
dcecc1968 Gasoline - 90 Octane, Ethanol Free (89), or additives Feb 6 2019, 07:46 AM
TheCabinetmaker Check your timing Feb 6 2019, 07:54 AM BeatNavy A well-tuned stock engine (with stock compression ... Feb 6 2019, 07:58 AM porschetub Loose valves are a clatter/rattle not a knocking,i... Feb 6 2019, 12:34 PM
914_teener
Loose valves are a clatter/rattle not a knocking,... Feb 6 2019, 12:55 PM Dave_Darling If it really is valve noise, the probable causes r... Feb 6 2019, 01:13 PM wndsrfr
Thanks for your suggestions. I will definitely c... Feb 6 2019, 03:34 PM bbrock At what compression should you start thinking abou... Feb 7 2019, 10:21 AM Dave_Darling
Side question: Anyone know why they raised the oc... Feb 7 2019, 03:52 PM Mark Henry
Side question: Anyone know why they raised the o... Feb 8 2019, 12:21 PM 914Sixer Check around at Pure Gas.com and see if there is a... Feb 7 2019, 01:12 PM Mikey914 I only run ethanol free and additive for lubricati... Feb 7 2019, 02:22 PM jfort this thread is close to my question so I'll co... Jul 11 2019, 02:17 PM FlacaProductions @mikey914 - what additive do you use?
this car is... Jul 11 2019, 06:58 PM |
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