Sudden loud engine noise!!!, Help me diagnose.. but be gentle! |
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Sudden loud engine noise!!!, Help me diagnose.. but be gentle! |
bondo |
Dec 3 2005, 07:27 PM
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#1
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Practicing my perpendicular parking Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California |
Ok, I've got a 914, with an unknown engine (serial is for RoW 1.7) that was rebuilt "several years ago". Just now I was shuffling cars... started it up, backed it down the driveway. I let it warm up for a couple minutes and shut it off. Then I went to move the MG so I would have toom to park the 914 next to it. The 914 was off for maybe 5 minutes. When I went to start up the 914, it immediately had a loud clack/knock. I drove it up the driveway and parked it next to the MG, and it made the noise the whole way. (about 75 feet) I shut it off, went to get the camera to record some videos. Then I started it up, and recorded these videos:
First is idling at about 1400 RPM, for 30 seconds. Second is idling with a few blips of the throttle, also for 30 seconds. The videos are 2.7 megs each. Thanks! |
Katmanken |
Jan 9 2006, 01:40 PM
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#2
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You haven't seen me if anybody asks... Group: Members Posts: 4,738 Joined: 14-June 03 From: USA Member No.: 819 Region Association: Upper MidWest |
If the oil is dirty, those VW lifters can bleed down and not repressurize after you start the car, move it in the driveway, and shut it off. Only use synthetic oil, change regularly, and use a good filter.
Hydros aren't great for air cooled and the overheating stretchy valve before breaky/valve seat fall from head issues. When you have solids, you go into the engine, adjust the valves and have a clue if the valves are stretching or the valve seats are moving. If the valve starts stretching or constantly changing, stop running it, it's time for a rebuild. With hydros it's set and forget. They sorta run ok, and adjust for a stretching valve or a seat as it loosens up until....BOOM, you got an engine fulla broken parts. Vanagons are water cooled and don't have as many overheating head issues so they hydros sorta work. As per swaping them out, if it ain't broke, don't fix it. I have heard of one or two lifters being replaced on an old cam, but it's a risk. After rebuilding air cooled engines and looking at the parts, those old cam lobes are usually all different sizes and lifts from lobe to lobe. All new hydros means all new cam to me. Hope that helps |
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