2long Posted January 10, 2022 Report Share Posted January 10, 2022 Symptom: heading uphill, shift from 2nd to 3rd a little prematurely, and I am hearing a bit of clattering from my motor. If I keep at higher rpm it does not happen. I suspect valve gear or something at the top end. Any suggestions? It has been a bit of a developing issue on a motor rebuilt a few years ago. Cheers Dan Quote Link to post Share on other sites
Hamish Posted January 10, 2022 Report Share Posted January 10, 2022 Sounds like it’s “pinking” or “knocking” this is a detonation, timing, fuel quality issue not really mechanical. Try a tank of the best fuel and check your timing. Quote Link to post Share on other sites
Lebro Posted January 10, 2022 Report Share Posted January 10, 2022 +1 try retarding the ignition timing Bob Quote Link to post Share on other sites
BlueTR3A-5EKT Posted January 10, 2022 Report Share Posted January 10, 2022 (edited) Slacken the fan belt and…..Wobble the water pump pulley and the dynamo pulley. Plus check security of the dynamo. Also check mechanical fan security. may not be the issue but will eliminate them before you start tearing into the engine. Edited January 10, 2022 by BlueTR3A-5EKT Quote Link to post Share on other sites
Motorsport Mickey Posted January 11, 2022 Report Share Posted January 11, 2022 Hi Dan, As Peter states the mechanical fan area is a good area to check for rattles. When the motor was rebuilt was the front pulley torqued up to at least 120 lb ft ? The manual says 140 lb ft but in deference to it's age I use 120 and in the many I've built they don't come loose at that. If they come loose the woodruff key in the crank batters at the keyway like a mini impact driver and can cut it's own slot there sideways into the pulley (worst I found when stripping made about 6mm !) bugger to get the pulley off until I sussed it. Mick Richards Quote Link to post Share on other sites
2long Posted February 13, 2022 Author Report Share Posted February 13, 2022 To follow up on this thread, it has been sorted! Case of “pinking”. Fresh high octane fuel was the first attempt - with little joy. Retarding the timing a bit did the trick. And I learned (by watching) how to use a timing light, twist the dissie a smidge after loosening the (whtiworth?) securing bolt, and also listen for the slightly lowering rpm. Thanks for the help guys! cheers Dan Quote Link to post Share on other sites
RogerH Posted February 13, 2022 Report Share Posted February 13, 2022 Well done Dan. Roger Quote Link to post Share on other sites
Hamish Posted February 13, 2022 Report Share Posted February 13, 2022 55 minutes ago, RogerH said: Well done Dan. Roger +1 nice to get a diy result. Quote Link to post Share on other sites
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