| Ignition timing issues [message #262955] |
Sun, 28 September 2014 21:31  |
kwharland
Messages: 246
Registered: November 2005
Location: Central Florida
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I'm going to start a new thread about my problems getting my engine running correctly since the focus has changed. I realize there's also a recent thread on this same subject but don't want to hijack it.
To bring everyone up to speed, I was having a problem with the engine bogging down badly when the throttle was partially opened and after having gone through the carb multiple times, was suspicious of a possible clogged exhaust. That was disproven as a problem and the last suggestion was to try fresh fuel. That proved of no benefit either although I did find the old fuel was foul.
I had previously disassembled the distributor and both cleaned and lubed all components, insuring that both the vacuum and centrifugal advances worked freely. I had set the initial advance at 12* with the vacuum advance disconnected.
I have a dial-back timing light that I've never trusted too much and I find I'm not alone with many professional engine builders preferring timing tape. This timing light was showing far less advance from both vacuum and centrifugal than I was expecting so I decided to go the timing tape route.
Prior to this, my research indicate that the correct vacuum advance unit was supposed to be a VC1847 that provided 12* of advance and that the centrifugal should add 20*. As it turns out, the vacuum advance is only 8* and centrifugal is 12*. So it's no surprise I have no power at 1500 to 3000 RPM. I have no idea where the PO had the initial timing set but I now suspect it must have been much more than 12* considering it ran fine previously.
I've removed the vac can and find that it's not correct, in fact it's actually stamped with the numeral '8' in addition to a '609'. I'm sure I can find a correct can but I'm not sure what's restricting the mechanical advance. I need to find another distributor and compare parts. I do see that the distributors built by Dick Paterson have 18* so I just have to figure how to correct mine.
1978 Eleganza II
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