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By oldcarmark - 15 Years Ago
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I am STILL working on my "won't idle in drive"problem.Think I might have found something.If I set the initial timing at 8 BTDC with all vacuum DISCONNECTED that should NOT change if it is put into drive? Yes or No? It is idling at around 700 which should not bring the centrifugal advance into play.Put it into drive-timing drops to 2 BTDC.Hook up the fulltime vacuum line idling in neutral timing is 18 BTDC.Runs good.Drop it in drive-dies.Increase speed on carb so I can at least check timing in drive.It has dropped back to about 13 BTDC.Engine vacuum has dropped from about 18 to about 13.This distributor was an exchange 57+ last year.If the timing is retarding as I slow down at a light for example as it is doing at idle-would this likely be the cause of my poor idle in drive?Going to pull the distributor for a look inside.What should I be looking for?This change in initial timing does not seem to be normal I don't think?
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By charliemccraney - 15 Years Ago
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If the timing and vacuum dropped from 18 in neutral, to 13 in drive then that indicates that the vacuum advance is working properly. Lower vacuum = less vac advance. More vacuum = more vac advance, to a point.
I don't remember if it's been mentioned yet. Are you sure that your damper has not slipped and the timing marks are in the correct position?
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By oldcarmark - 15 Years Ago
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Charlie1 I know the vacuum advance is working.The initial advance once set should not change regardless how much it advances as its being driven?This is what appears to be happening.I checked the timing marks using some info that Hoosier told me.They seem to be correct on the damper.Also added a timing tape so I can see whats happening as speed is increased.
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By charliemccraney - 15 Years Ago
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If the engine is running at a higher speed than idle, and/or the vacuum advance is active, then you will find the timing to be higher than initial. If you're running manifold vacuum to the advance, then you should see higher than initial timing when idling. If you're running ported vacuum, then you should see initial advance when idling as the vacuum should not be active. So you have a problem if you're running ported vacuum. If you're running manifold vacuum, then it's running right.
Does the initial advance stay at 8* if you disconnect the vacuum advance? Does the timing advance smoothly as the engine speed is increased?
Again, I don't remember, which carb are you running with the 57 up distributor?
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By Speedbump - 15 Years Ago
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You need to look for small(aftermarket) or weak/sloppy springs holding the weights on the centrifugal advance plate. You're right, 700 rpm shouldn't start the advance unless someone did it on purpose or that part of the distributor is just worn out. I have found the key to idle in gear with lots of cam is lots of initial timing with the advance coming in pretty early, by 2,600-2,800 rpm or so. That also means you have to change the advance stop bushing so there is not too much advance put in at full advance rpm. IMO, you only want 36-40 total. sometimes you can use manifold vacuum to help, but in many instances it does exactly what you said.....goes in gear, rpm falls, vacuum falls, advance goes away, engine dies. As an example, the last one I did had 24 degrees of initial with 18 degrees of mechanical, all in at 2,600 rpm and the advance stop set for a total of 38 degrees. With a cam lift of .580 and 238 intake degrees @ .050 it will idle at 1000 rpm in neutral and 750-800 in drive. I do use a 2500 stall converter with the AOD....it sounds like a hot rod and I love it! It took three tries to get it right and I cheated this time and used an MSD distributor which is made to tune this way, but it can be done with a ford unit, just more work. Good luck.
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By oldcarmark - 15 Years Ago
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I have a stock cam.I just took the dist apart and cant see anything obviously wrong.If I set initial timing at 8 btdc that should stay constant regardless of what vacuum or cent advance does.Still looking.390 Holley and with the idle speed set at a reasonable 700 approx even the ported fitting in the carb is active.Not as much as the non-ported obviously.
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By charliemccraney - 15 Years Ago
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oldcarmark (5/13/2010)
If I set initial timing at8 btdc that should stay constant regardless of what vacuum or cent advance does.Still looking.390 Holley and with the idle speed set at a reasonable 700 approx even the ported fitting in the carb is active.Not as much as the non-ported obviously.
With vacuum disconnected and the engine idling, the initial should always be at 8. If you rev it and let it return to idle it should return to 8. Because you have vacuum at the ported and manifold ports, with the vacuum advance connected, it will be advanced from 8 at idle. In the case of manifold vacuum, this is normal. In the case of ported vacuum, it is not. If you disconnect the vacuum advance while idling, it should return to 8.
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By PWH42 - 15 Years Ago
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Mark.......I'm sure not an expert,but try going back to the basic setup that Ford intended when they built it.Connect the vacuum to a ported source,not manifold vacuum,set the timing at 6 degrees with the vacuum disconnected,make sure your distributor clearance is correct,make sure valves are set .019 clearnce and idle speed is around 550.Try all this and see what happens.My nearly stock engine does the same thing yours does if I run manifold vacuum to the distributor.
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By oldcarmark - 15 Years Ago
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Thanks Guys! Been playing with this all afternoon.Set the timing higher+manifold vacuum.Set it back from 12 to 6 +manifold vacuum.Set it higher than 12.Speed ingreases ,still dies in drive.The result is the same.Idles great in neutral.Drop it in drive-dies.One thing I dont understand.Before this rebuild the motor would idle fine in drive and the ported vacuum fitting was not activated.Now I have had to increase the carb speed to the point that the port is active and the idle transfer slot is starting to show which I understand as much as possible should be covered by the throttle plates at idle.rI have spent the last 3 weeks trying everything I can think of or was suggested.Has not improved my trouble one little bit.I am lost at this point.I may take it to someone who has a scope and see if SOMETHING shows up when it goes into drive.Maybe a fresh set of eyes and hands would be good idea at this point.Hi Paul! I have tried it with stock setting of 6 BTDC.The ported vacuum outlet is slightly actice-less than full manifold vacuum.The ignition is Accel points replacement.I reinstalled the points last weekend to try it.No better.Reinstalled the Accel.I have reset the valves 3 times.Tuesday I tried the 1/4 turn method.The rockers were not redone when I did the motor.I cant set them hot.I have the old style locknut adjusters and with the mod to the camshaft groove and good oil pressure I have oil running over the edge of head within about 30 seconds of starting it.Thank you for the suggestions.One other thought I had was possible transmission or TC problem.Talked to a transmission guy this mornig who has experience with Fordos.Doesnt see how this could be a tranny problem.
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By Speedbump - 15 Years Ago
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You can buy or make an in car TDC checker to make sure that timing mark hasn't slipped and you're getting bogus timing info from the light. While apart, lightly lube the weights on the pivots with thin film of grease. Make sure the rotor shaft rotates, by hand, as far as the stop lets it(against the springs) and comes back to the same spot when released....and it should be smooth and easy. In a stock unit, there should be NO slop at all when the the shaft is in it's non advanced rest position. If there is, that could cause your timing to be irratic with changing rpm's.
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By oldcarmark - 15 Years Ago
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Hey Speedbump. I asked Hoosier about verifying camshaft position to crankshaft TDC.On either #1 or #6 turn motor until both intake and exhaust are dead level(i.e open same amount).Crankshaft should be at TDC or very close to it.I did this and as far as can tell the damper is still accurate.Also wanted to verify that I did not install the timing gears incorectly.They are correct.16 BTDC marking is about centre of the wide spoke which was something that was posted on a topic awhile ago.I think my marks are still correct and as I said I added a tape when i assembled the motor for more accurate timing past the old useless marks on the damper.
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By GREENBIRD56 - 15 Years Ago
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Mark - Regarding the Holley carb You shouldn't have to open the primary throttle to the point that the ported vacuum is active at idle. The throttle stop should hold the primary butterfles so that the idle transfer slot shows as a "square" viewed from underneath. I believe you've got the mixture needles all set-up by now, they should be withdrawn from "stop" a full turn or more - correct? I don't know about you - but it is very hard for me to keep myself from playing with the primary throttle stop - but it will screw up the transfer slot / primary butterfly relationship every time. And you will get what you've got - other carburetor circuits are becoming active and defeating your opportunity to tune it. On the carb, viewed from the bottom, there is a small set screw located beneath the vacuum secondary pot that functions as the "stop" for the secondary butterfly shaft. There is a "fixed" idle fuel supply available to the secondary and opening the butterflies a slight amount will provide fuel/air to the engine. Because the little inverted set screw is a pain to access - I usually resort to bending the little sheet metal tab above it with needle nose pliers a tiny amount. Often - this will allow setting the primary stop screw where you want it and provide idle air/ fuel to run the engine. Using this technique - leave the distributor vacuum line open and the two carb vacuum points that might feed it, plugged. Another "air supply" for the engine is the PCV - it should be regulating itself as far as air flow - but the carb has to supply fuel for that air source as well. If you plug that PCV port on the carb - and fully tune the engine, hooking up the PCV to the valley later on will screw up your idle tuning - so it needs to be on there and working. Also make sure the choke system is out of your way and not providing a false "stop " for the primary - holding it open. Tweaking the tab under the secondary should make it possible to get the engine running - with the primary stop located as desired - and get the engine speed into a useful idle set-up range. And you should be able then to unplug and "test" the ported vacuum source and find no vacuum. The distributor should be able to hold your "initial" advance and always return there - if not - there is a mechanical reason that must be found.
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By Pete 55Tbird - 15 Years Ago
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Mark You wrote" am STILL working on my "won't idle in drive"problem.Think I might have found something.If I set the initial timing at 8 BTDC with all vacuum DISCONNECTED that should NOT change if it is put into drive? Yes or No? It is idling at around 700 which should not bring the centrifugal advance into play.Put it into drive-timing drops to 2 BTDC." CORRECT. The timing should NOT change at all. If it is changing with ALL vacuum advance eliminated then it MUST be mechanical advance. How about if you switch the two springs on the mechanical advance and try it? What do you get then? Then lock the weights in a fixed position and try it. Seems to me that the loss of the extra 200 RPM from FOM in neutral to FOM in drive is causing a decrease in ignition advance and might be a big part of the problem. If you can find someone with a distributor machine that would be worth checking. Pete
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By oldcarmark - 15 Years Ago
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Steve! Sent you a PM.Let me know if you did not get it.Seems to be an awful lot of PM's getting lost lately.
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By oldcarmark - 15 Years Ago
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Hi Pete! When I took it apart today I was looking for anything obviously wrong.Looked OK.Now the weights are the triangle shaped setup.18L on both weights which I assume means 36 at the crank plus whatever initial advance would give total advance available IF all advance can be activated by engine RPM?How would I lock the weights?And yes the loss of RPM when put into drive is opart of the problem.Should be more like 25-50 as per shop manual.By the way I am getting real good at re and re the dist and getting it running again!
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By charliemccraney - 15 Years Ago
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Mark,
The next time you have the distributor apart, take a closer look at the weights. One side is most likely marked 13L. If it is, flip the rotor around so that the corresponding 13L slot is engaged. Try that for a while, play with the initial timing, and see if you like it. This shouldn't affect the current situation so there's no need to dig back in at this moment.
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By oldcarmark - 15 Years Ago
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Thanks Charlie?!This is something I am interested in doing once I get it straightened out.
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By oldcarmark - 15 Years Ago
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Steve.Sent another PM.Let me know if you did not get it.Thanks
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By GREENBIRD56 - 15 Years Ago
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Mark - this shows the slots in the upper rotor shaft that control the total amount of centrifugal advance. When the pin shown in the 18L slot is switched around to the 13L slot it reduces the advance 10 crankshaft degrees. 
Don't pay a whole lot of attention to what is stamped on the weights themselves.
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