KitCarlson
Well-Known Member
If you think electronic advance control at this point will fix your problems .....
Checking TDC better plan.
Checking TDC better plan.
Only runs 40 Degrees advanced
- Thread starter mr65cuda
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yellow rose
Overnight Sensation
Then you SHOULD have turned the engine over 1 turn more (180 degrees) and LOOKED and VERIFIED that the cam is where it SHOULD be.
It's simple. You were half way there. You looking at the dots or what ever doesn't make me feel warm and fuzzy.
Do like I said and VERIFY by valve opening on crossover (overlap) and post a picture of what the rockers are doing. Then you'll know if the cam is straight up, advanced or retarded.
OK OK by popular demand I have made a piston stop out of up a spark plug and I am in the process of trying to crank the engine over and see where it lands it’s hard because I only have a couple inches between the crank pulley and the radiator I will report back. And no I don’t want any automatic timing advance at this point all the timing is in the distributor now
I’m waiting for the “AH HA” moment. Its got to be a stressful situation.
I know it would make me absolutely batshit crazy.
I know it would make me absolutely batshit crazy.
Internal combustion engine, so simple, yet so hard. Have you eliminated possible cam timing, fuel distribution, or ignition timing problem. I keep a points distributor and a good carb on hand just for occasions like this.
cam timing is easy to verify. follow the advice given
cam timing is easy to verify. follow the advice given
I would like to present a scenario if i may.
If you had a stock type ignition system and could install it,disable efi.
Then rough set timing and check while cranking engine.
Perhaps the timing would be ok,for a carbed engine.
Throw a shot of gas in throttle body and see if it fires.
If i diagnose a fuel injected car for a bad pump,i give it a snort of gas and crank it. If it fires i know im on on the right track, be it a pump or delivery issue.
If you had a stock type ignition system and could install it,disable efi.
Then rough set timing and check while cranking engine.
Perhaps the timing would be ok,for a carbed engine.
Throw a shot of gas in throttle body and see if it fires.
If i diagnose a fuel injected car for a bad pump,i give it a snort of gas and crank it. If it fires i know im on on the right track, be it a pump or delivery issue.
KitCarlson
Well-Known Member
With efi engine, pull injector power relay, efi connector, or injector connectors, disabling injectors. I wire my cars to make it easy.. Then crank for testing ignition. Also ground plug wires, or coil to cap wire. Clamp-on timing lights trigger on current, not voltage. It is a way to get around an electrical noise, and safety issues. The timing lights can be used on distributor to observerify rotor and pickup/reluctor positions. There will be 4 cylinder observation per engine revolution, with cla,p at coil hv, but you can visually sort out @ #1.
MSD CDI often generates electrical messing with efi measurements and ignition triggers. Recently a member had problems with coils, and found balast resistor addition helped. It helped likely, when current reduction reduced electrical noise. I am sure by the time noise is reduced, an inductive hei would be superior.
Please be safe, do not repeat hand spinning, with sparks and fuel spurting....
MSD CDI often generates electrical messing with efi measurements and ignition triggers. Recently a member had problems with coils, and found balast resistor addition helped. It helped likely, when current reduction reduced electrical noise. I am sure by the time noise is reduced, an inductive hei would be superior.
Please be safe, do not repeat hand spinning, with sparks and fuel spurting....
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OK guys the answer we all been waiting for. I finally got the piston stop in and cranked around enough to determine it is off by 5° I wish this was the aha moment but I don’t think it’s my problem. Now I will try the valve crossover thing that another member suggested. And yeah I did disconnect the fuel while I was testing ignition so I didn’t have to constantly flood the motor when I was trying to just look at the timing. Or trying to find top dead center I have cranked it over a lot.
yellow rose
Overnight Sensation
So your 40 degrees is really 35. Glad you found it. I can't tell you how many times guys will just set the timing and think it's good rather than tune for power and then see what the number is.
5* of what? Crank or cam timing?
When I measured the damper real top dead center Mark was 5° advanced Instead of the TDC Mark
yellow rose
Overnight Sensation
Crank timing. His 40 was really 35.
I can tell you I've seen many "pro" engine assemblers who can't find and verify (and correct) TDC or degree a cam. They almost never check P/V clearance and if they do, they do it wrong and give up compression and leave way too much clearance.
That's why it's so expensive to assemble an engine. I've done some engines on their first build that need to be mock assembled 8-10 times to check and verify and correct things. Everything SHOULD be written down, on paper so there is a record of it, and when the engine comes back it, the sheet pulled and all the numbers verified on disassembly.
Time is money and it costs to do it right. I feel bad because the OP spent a ton of time getting this sorted and it should have been done on assemble. So in the long run, the time and frustration was way more than the cost of doing it correctly.
Again, I'm glad the OP got it sorted out and found the issue. But it's a bummer how much time and energy he spent getting it done.
The *5 does not solve the program
My suggestion is. Get it started at the *40 setting on #1 idle. Then move the timing light to #6 and read the timing advance. Is it at *40? This will answer the twisted cam idea. Yes cams twist it's just a fact of "lift" or life. 1969 indy race engine twisted cam you could check with Ike Boyd but he's dead. Check with some of you guys idol hughes.
Ask why he doesn't check timing between 1 & 6. Plausible deniability of the difference from the front and the rear of the camshaft.
I'm not saying this engine has a twisted cam, I'm just saying check it.
Good point, I just remember they used a timing light. They did have the valve cover off tho.
Could ask hughes "he may charge you for the answer or deny he ever checked it".
Use a piston stop to confirm TDC on #1 cylinder and to properly index a timing tape marked every 90 degrees. Take the valve covers off to check rockers to see that the valves are closed on each cylinder at TDC on each cylinder.
I was 14-15 at the time. My attention was on girls and cars so wasn't paying attention to everything being said or shown.
But the main thing would be #1 at top dead center to start the show. Then checking for tdc on #6 without changing the initial setting of The harmonic balancer and cam relationship.
All he's done at this point is determine the balancer "or something" on the crank is off 5*. He still doesn't know "where everything else is" "in relation to". So, this is only one small puzzle piece. At this point, I am going to sit back and enjoy the entertainment.
Correct the five Degrees off wasn’t any big deal. That didn’t fix anything but it was a good thing to check it could have been. I won’t have time for a few days to work on it I feel like yanking it but I’m gonna try a few more things mostly your guises suggestions because they are all good
It’s been a quite a while since I started this post just so people don’t have to go back and read the whole thing the very short version is the starter turns the crank crank turns the Kam the Kam turns the distributor distributor was locked up so the starter made it jump out of its timing slot to a three times and it hasn’t ran right sense. new intermediate shaft new Distributor
Don’t know why it sent. but anyway. so I took the timing cover off check the timing chain it is still dot to dot and keyways are still intact so it seems like only thing left is the Cam somehow twisted which I think is impossible but I’m still trying your guys suggestions before I yank it.
MobileCustoms
You can twist perceptions, reality won't budge
I think I would pull the timing chain off and set everything back to where it is supposed to be using a degree wheel and then go from there making sure the distributor is phased correctly, the reluctor is right side up, the plug wires are in the correct order and on the correct plugs and it is not 180 degrees off. Pretend that you are setting it up for it's first run.
If there is any of that which you are not familiar or comfortable with doing yourself, then look for someone who experienced is to help you do it all. and do all of it with the proper tools and measurements... no more shortcuts!
If there is any of that which you are not familiar or comfortable with doing yourself, then look for someone who experienced is to help you do it all. and do all of it with the proper tools and measurements... no more shortcuts!
KitCarlson
Well-Known Member
Seems checking valve timing on #1, and #8 could verify cam twist or not. They should be identical, but 90 crank degrees apart. # 1 at front of cam, #8 at rear, firing order 1,8,....
Me still thinks wrong polarity on pickup sensor, offsets rotor phase enough, that huge timing advance lets rotor, line up to cap terminal. Sounds like at desired timing 13-15 deg, no spark at plug, you said that.
Tried to give info of how to verify rotor and reluctor position based on spark event. Never got strait answer. You could swap polarity on pickup wires, static time it to 13 degrees give it a try. I'm out.
Me still thinks wrong polarity on pickup sensor, offsets rotor phase enough, that huge timing advance lets rotor, line up to cap terminal. Sounds like at desired timing 13-15 deg, no spark at plug, you said that.
Tried to give info of how to verify rotor and reluctor position based on spark event. Never got strait answer. You could swap polarity on pickup wires, static time it to 13 degrees give it a try. I'm out.
yellow rose
Overnight Sensation
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