Guest RonJar Posted May 3, 2012 Share Posted May 3, 2012 Tried to use a timing light to check my ignition timing and found out the fly wheel wasn't installed in the correct position.I set the timing by ear, moved the distributor to where I had the smoothest idle. It seemed to run pretty nicely.When out on the road, I advanced the timing to try to get it to ping when accelerating from 20mph in high gear. No ping. I advanced it a bit more, still no ping but now the idle was getting rough from too much advance I guess. Engine cranks good, doesn't act like it has too much timing.Should I be able to advance the timing enough to get a ping under load?Should I leave the distributor where it gives me the smoothest idle?Sure wish the flywheel was on right ...... Thanks in advance .... RonJ Link to comment Share on other sites More sharing options...
hchris Posted May 3, 2012 Share Posted May 3, 2012 Another method of setting timing is to use a vacuum guage, dont know if you have a fitting where you can hook one up to the inlet manifold, but if so use this to find the highest stable vacuum indication ( approx. 20 inches) at idle as you move the distributor to and fro.Failing this go back to your on the road method where you achieve both good idle and acceleration; no definitely dont go to pinging under load!! Link to comment Share on other sites More sharing options...
Guest Grant Magrath Posted May 3, 2012 Share Posted May 3, 2012 Is it possible to pull No1 spark plug and poke something like a straw down there, turn the engine by hand, find TDC, then make a mark on the flywheel? It would give you something to go on. Have you tried hooking the light onto some of the other leads to see where you're at with the flywheel?The vacuum gauge can go on the fitting for the wiper on the intake manifold.CheersGrant Link to comment Share on other sites More sharing options...
Guest RonJar Posted May 3, 2012 Share Posted May 3, 2012 @ hchris, I've used a vacuum gauge, I can advance past the smoothest idle and get a higher reading but the engine picks up a "tremour" while idling at this point. Sounds like too much advance but no ping inder load and cranks good when hot. Do you think I should leave it where the idle is smoothest?@ grant magrath, are you saying the timing marks will be in the correct position for one of the other cylinders? Some engines were made to be timed with a cylinder other than #1. Be easy enough to try, for sure. I'd thought of remarking the flywheel like you suggest, but there is such a long "dwell" period where the piston is stationery at TDC and the crank can swing a few degrees either way. Split the difference I guess.Thanks to both of you! .... RonJ Link to comment Share on other sites More sharing options...
Steve_bigD Posted May 3, 2012 Share Posted May 3, 2012 Because the compression ratio is only 6.2:1 these engines will almost never ping on today's regular gas even when the timing is way advanced beyond limits. I set mine with the vacuum gauge method. I did try to advance it as much as possible together with smooth running and found that with 15 degrees or more advance over the 4 degree spec the engine became hard to start when hot. I wound up somewhere around 10 degrees total initial advance. This is on the 248 engine as I have a series 40-41 model.Steve D Link to comment Share on other sites More sharing options...
DonMicheletti Posted May 3, 2012 Share Posted May 3, 2012 With the flywheel in the wrong place you probably cant go to another cylinder with a timing light unless it is on 180 degrees off, in which case you can use #8 cylinder - but if Murphy is working you wont be that lucky. I had the same problem with my '38 Roadmaster and did exactly the same thing you are doing. I finally straightened it out when I replaced a clutch. Link to comment Share on other sites More sharing options...
DonMicheletti Posted May 3, 2012 Share Posted May 3, 2012 Oh yes - there are 6 mounting bolts and 8 cylinders - so it usually does not match up Link to comment Share on other sites More sharing options...
DonMicheletti Posted May 3, 2012 Share Posted May 3, 2012 Wait - I have that all wrong!! Link to comment Share on other sites More sharing options...
hchris Posted May 3, 2012 Share Posted May 3, 2012 @ hchris, I've used a vacuum gauge, I can advance past the smoothest idle and get a higher reading but the engine picks up a "tremour" while idling at this point. Sounds like too much advance but no ping inder load and cranks good when hot. Do you think I should leave it where the idle is smoothest?@ grant magrath, are you saying the timing marks will be in the correct position for one of the other cylinders? Some engines were made to be timed with a cylinder other than #1. Be easy enough to try, for sure. I'd thought of remarking the flywheel like you suggest, but there is such a long "dwell" period where the piston is stationery at TDC and the crank can swing a few degrees either way. Split the difference I guess.Thanks to both of you! .... RonJYes leave it where it is, sounds like you have it pretty close; as also mentioned ,because of the low compression rating of engines of this era you dont have to be too precise Link to comment Share on other sites More sharing options...
Guest RonJar Posted May 5, 2012 Share Posted May 5, 2012 I ended up using a vacuum gauge and ear method.Idle is decent, lot's of low end pull and no pinging.Thanks for all the input.RonJ Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now