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danimal |
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#1
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Newbie ![]() Group: Members Posts: 4 Joined: 18-September 04 From: Monrovia, CA Member No.: 2,780 ![]() |
havent had the car for long, it was backfiring so I figured I'd adjust the valves.
Pretty sure I did everything right. I re-checked 4 times. Now it runs ok but it's really loud. I know some valve clatter is ok, but it sounds like a diesel rabbit. I know it's hard to recreate a sound on a forum post but it sounds like something is pounding. Is this normal or did I miss something. |
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SGB |
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#2
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just visiting ![]() ![]() ![]() ![]() Group: Members Posts: 4,086 Joined: 8-March 03 From: Huntsville, AL Member No.: 404 Region Association: South East States ![]() |
Do you have any idea if it is a stock cam. I replaced mine with a hydraulic one made by Webcam. It is (or was) a fairly common improvement at one time, although there is now greater debate on the value provided. The idea is to eliminate or reduce valve adjustment every 3k miles. They tend to be noisy for a few seconds if the engine has been sitting for more than a day or two before it is started. More importantly, they are hard to set properly. I messed mine up tightening 'em up too much, trying to make 'em "quiet", but now I finally did get them set right. Do a compression test. When I did I found out I had low compression in two cylinders- my intakes were to tight and what I thought was valve noise was actually combustion leaking into the intake manifold. If you think yours are hydro, the important thing is to commpress the oil out of the lifter bfore adjusting. Each lifter has a little oil chamber that is held open with a light pressure spring inside. I went round squishing each pushrod down, then tightened the adjuster screws about 1/4 turn past when I felt the spring in the lifter start to resist. Then I ran the engine at 2000 rpm for about 30 sec. I went round to each valve again, checking to see if the oil chamber in the lifter had pumped full. With hydro valves there is no "clearance". The oil in the little chamber pushes the pushrod up against the rocker even when cold, so if there was any "clearance" I tightened the screw about 1/16th turn. After another "pump-up" run to 2k rpm for a bit, I checkd again. Then I did a final compression check to make sure there were not ant too tight. I can't really tell you how to determine if yer car has this cam and lifters except to see if you can compress a pushrod and it feels squishy or pull off a rocker assembly so you can take out a pushrod and pushrod tube atleast far enough to get a lifter out and see if it has holes in it...
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