Ignition Timing Q

[visionguru]

I hooked up a timing light at idle (I didn't disconnect the vacuum advance YET). The timing marks looks like this:
http://img497.imageshack.us/img497/4003/timing7qr.gif (http://imageshack.us)
The pointer is lower than the red mark and the mark below it.
Can anyone explain to me? Is this advanced or retarded? My car shakes a bit at low idle, do you think I can correct it by adjust timing?
Thanks.

[A20A1]

Check how much vacuum you're pulling...

You're supposed to disconnect the vacuum advance to rule out a vacuum problem or a bad advancing unit.

If the base timing is right but the advance is off then there is something wrong with the advance.

If the base timing is off, then it could mean an engine problem somewhere... or you simply need to turn the dizzy.

advance would make your car idle rpm go up a little... at least I think thats how it'll react. So thats one way can tell what rotating the dizzy is doing.


is one of the pointers cold advance perhaps.

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[shepherd79]

you timing is retarded a little. you need to advance it.
when you advance it, the engine will sound faster and smoother. don't do it too much or you can cause backfire or dieseling after shut downs.

[Honda-Master]

Check how much vacuum you're pulling...

You're supposed to disconnect the vacuum advance to rule out a vacuum problem or a bad advancing unit.



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I totally disagree with you,,,,,,,

,,if you pull off the vacc hoses at advance diaphram than your timing will be retarded,, you are supposed to chk timing with hoses connected altough only the inner hose matter because it has vacc, the outer hose only has vacc when engine is cold,,,,,,,,
the proper way is to,, first off ,make sure you got vacc on the inner hose ,, if not you should fix the source,, if you got vacc ,with hose disconnected ,,, get a vacc gauge and apply vacc at the inner hose diaphram ,make sure it holds vacc ,,if it does then, reconnect hose and you can set timing properly, if diaphram leaks you won't be able to set the right timing , it will be retarded ,you should replace the vacc advance diaphram, and depends how bad the diaphram is leaking you could have an erratic idle ,,

if you cannot set timing by just loosening up the distr and turning it,,most likely cam timing is off // ..
once timing is set,, when you rev engine up ,,you should see the timing advance , if not the distr advance weights could be frozen , i have seen a shit load of these, and it will cause slugginh take off ( hesitation ) from a stop ..,,

[Honda-Master]

one last thing i forgot to mention,, you set timing with engine hot, at normal idle ,, you got different marks on the flywheel,,, the white is top dead center, set it at the red mark , there are also 2 marks next to the red 1 on each side,, they are, 2 degrees advance and retarded ,, .

[A20A1]

I dunno, stock I've always set my timing to the "T" mark area with advance disconnected, then when I plug in the advance lines the pointer ends up in the right spot. It works every time so why is that the wrong way?

Maybe carb and efi are different.

I don't use the vacuum advance as a sure method anyways because I pull on average 10" - 18" with my current cam grind. Idle is steady at 800 rpm in gear (automatic)... I'll end up advancing the distributor just to make up for the drop in vacuum. If I could I would change out the spring inside the diaphragm.

[Honda-Master]

ok,, A20a1 ... i missed the part where you said to set timing at tdc with hose disconnected... my bad ..:) ,, if you set it at tdc with hose off i am ok with that ...

i feel disconnecting the hose and plug it up would take longer time to achieve the same results ,, and working flat rate you do jobs the shortest way possible but without compramising quality,,...

[kw_da]

Be careful when using the timing mark on the drive plate if the car has been worked on. When I had my clutch done, they replaced the drive plate with one from a carb engine (mine is fuel injected), which has different timing - had to buy a new timing gun to set the timing.

David

[visionguru]

Honda FSM is really confusing on ignition timing adjustment:dunno: . On the 86 Accord FSM, page 24-4, basically it says (skipping those vacuum checking stuff)

Disconnect and plug 2 advance vacuum hoses;
Adjust ignition timing to 15 degree BTDC (before TDC?) at idle in gear (for automatic transmission).


As far as I can understand, the RED mark is the 15 BTDC. The WHITE mark is the TDC or 0 BTDC.

Another confusing part is the "idle in gear", shouldn't it be "idle in park"?

OK, from the suggestions by A20A1, Honda-Master, the goal of adjusting timing (assuming there is no defective parts) is:
With advance vacuum hoses disconnected, the pointer should be aligned with TDC (WHITE mark);
With advance vacuum hoses connected, the pointer should be at the RED mark.

So, if there is no defective parts, what's the point of disconnecting the hoses? Why not simply adjusting to the RED mark with the hoses connected?

Assuming there is something wrong with the advance, if set to WHITE mark (disconnecting the hoses), when plug back the hoses, the timing will not be at the red mark. But if setting the to the RED mark, the timing is correct even though there are problems. No? Still confused.

[Honda-Master]

[QUOTE=visionguru]


So, if there is no defective parts, what's the point of disconnecting the hoses? Why not simply adjusting to the RED mark with the hoses connected?


QUOTE]

that is the point i was trying to make...

if with the hoses connected you are not on the red mark ,and if you cannot obtain the correct timing by loosing up the distr and turning it a bit,, if you have to totally get distr to one side to get to the red mark then something is not correct , when properly timed distr should be almost smack in the middle of the adjustment slots,,,,, if timing is off... chk to see if ,,first of all you get vacc at the inner hose, 2 apply vacc to diaphram make sure it holds vacc,,if ok,, you need to chk the cam timing make sure the bottom and top ends are timed properly ..

[88Accord-DX]

I never seen any freaking red marks when timing my Accord. I just see the "T" mark & the 15 degree BTDC marks. My shit was bouncing around (timing gun flashing at the flywheel) at one time when I was timing it before I broke into the engine.
Has anyone had the timing marks bounce around erractic while vacuum lines disconnected and plugged while timing it with an inductive timing gun?

[Oldblueaccord]

I dunno, stock I've always set my timing to the "T" mark area with advance disconnected, then when I plug in the advance lines the pointer ends up in the right spot. It works every time so why is that the wrong way?

Maybe carb and efi are different.

I don't use the vacuum advance as a sure method anyways because I pull on average 10" - 18" with my current cam grind. Idle is steady at 800 rpm in gear (automatic)... I'll end up advancing the distributor just to make up for the drop in vacuum. If I could I would change out the spring inside the diaphragm.

changing the mechanical would help your idle vacuum. If you can soften the spirngs it will advance in at lower rpms.
If ours can be adjusted.

wp

[A20A1]

Okay I'll try that.

[Oldblueaccord]

http://chevyhiperformance.com/howto/97438/

http://go.mrgasket.com/pdf/29014.pdf


http://www.4secondsflat.com/Ignition.html

this place does this for a fee

http://go.mrgasket.com/AskTechResults.aspx?BrandID=12&ID=108152

million more on google. Im hoping ours is the same basic setup as others are. I forgot to look in the book and I'm at work atm.

wp

[Oldblueaccord]

Helms p 24-18 and 19 they call them govener springs on the govenor weights.

wp

[2oodoor]

Are these cars different than others that use vacuum advance? Other makes of cars that use VA :the timing procedure is remove and plug the lines at the vacuum adv. on the distributor. Then set the base timing at whatever the spec says such as the example ...15 degrees in drive with ac off, etc. Then reconnect the vacuum advance hoses. To test the vac. advance connect timing light, tach, or just listen to the motor and connect an outside vacuum source like a mighty vac tool to juice some vac to the servo. If the motor speeds up or moves up in time then the vac advance servo works. The vacuum advance is only supposed to work just off idle, part throttle to full throttle to "lead in" some advance before the centrifical (or weights/springs) kick in and move the pickup plate in the distributor thus full advance. Most FI motors use electronic advance. Some smog (post 78 to 88 year model) motors or electronically controled carbed motors use vac advance wierdly like the vaccum advance actually retards because the vacuum is being applied at idle or manifold vacuum instead of ported vacuum, then a thermo swithc or electronic solenoid cuts off the vacuum to vac. advance can.

[2oodoor]

Ok, any takers on my question . Are these cars A20 , different than most other cars regarding the ignition timing check procedure in that you leave the vacuum advance connnected and set the mark to spec. Thus correct ign timing is achieved at idle with vaccuum being applied to dist. (not just hooked up, but hooked up and pulling the vacuum can on the dist.)

[Oldblueaccord]

No your correct in the operation.

BUT my FI A20 has 2 vacuum advance moduals(2 vacuum lines) in it. What exactly they do is kinda a mystery. The Helms manual and a search here might better explain it to you.


wp

[bobafett]

on an efi 86 (and probably 87-89 as well) there are supposed to be 2 vaccum lines going to your dizzy.

the inner one is your normal vaccum advance port. the outer one is COLD ADVANCE. this should pull vaccum as your car is warming up to help keep it running smoother by advancing the timing for you.

this is why the manuals always say to adjust timing on a warm car. with the COLD ADVANCE out of the equation you just need to figure out the normal advance which is the inner vaccum line, and the only one that really actually matters.

i dont know if i am making any sense, or if you guys were even asknig something.... lol...

[Oldblueaccord]

Ill take a look at that when I get around to checking the timing on my baby. I got a long trip to take to NY in October.



wp