Road Test, Slow acceleration and valve chatter |
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Road Test, Slow acceleration and valve chatter |
VA_914 |
Oct 25 2020, 01:12 PM
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#1
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Newbie Group: Members Posts: 4 Joined: 31-March 08 From: Hampton, VA Member No.: 8,873 Region Association: MidAtlantic Region |
I am finally road testing my 2.0 restoration and haven't quite got it right yet. It starts fine, runs smooth idling or revved up in the driveway but on the road test it accelerated slow, with what sounds like valve chatter when I give more gas to accelerate. It wouldn't go over 3000 rpm in 1st, 2nd or third. I tweaked the timing a bit and it seemed to get better, less chatter and almost up to 4000 rpm. Suggestions, comments; am I on the right track?
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Superhawk996 |
Oct 25 2020, 01:53 PM
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#2
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914 Guru Group: Members Posts: 5,806 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
sounds like valve chatter. (IMG:style_emoticons/default/welcome.png) I'm going to suggest what you're hearing is detonation or "ping", that could maybe be described as a clatter or chatter sound. Never heard of the term valve chatter that could be put in the context of acceleration. What freqently happens is that as you tip in on the throttle the mixture goes lean and/or you're running way too much timing advance and that induces detonation. Detonation will damage an engine very quickly. Maybe you can describe the nose a bit more if you don't think it matches my description. The fact that you can't rev to more than 3000 RPM under load says something is very wrong. Likewise that it got better and the "chatter" decreased when you tweaked it says something. When you say you tweaked the timing what does that mean? There is a timing specification that needs to be set with a timing light. Is that what you did or are you just moving the distributor and quessing? Way to many factors to guess at. Also depends on whther engine is still Fuel Injected, running carbs, and whether or not it even still has the proper distributor in it. Need more information and and folks will try to help. |
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