

| Subject: | <No subject> |
| From: | John Rodgers |
| Date: | Fri, 12 Nov 2004 18:56:54 -0600 |
Don Williams wrote: > I did an overhaul this past summer on an 84 1.9 waterboxer engine. It > seems > to run like a charm but is gutless. I had an aircraft engine rebuilt once. Everything was good, compression, ran good, etc. Problem was, in spite of the engine running smooth like a champ, it was gutless. Would barely produce enough power to even get off the ground, much less fly away anywhere. This engine did not have hydraulic lifters, but solid lifters, so I had the mechanic perform what was know as a "Hot Valve Timing Check." That is with the engine being in a cold state, the engine valve clearances were set as if the engine were hot. The valve cleearance specifications for this were provided by the engine manufacturer. Once that was done, the timing and the valve opening and closing was checked using a degree marked device mounted on the crankshaft. Turned out the valve timing was wrong, and therefore the cam timing was out one or more teeth. . The intake valve was opening late, and the exhaust valve was closing early. The significance of this is that the fuel air charge going into the engine was less than it should be, and the scavenging of the exhaust gases from the cylinders was less than it should be. The final consequence of this was a power loss. There are a number of causes for power loss, if the compression is good. Cam timing could be the problem here. Hope this helps. Regards, John Rodgers 88 GL Driver
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