Wandering Timing Magical Mystery!

You can RANT and RAVE to your hearts content here instead of clogging up the Q&A Technical Forum!
Report any offensive posts to [email protected]
Post Reply
User avatar
Major_Tom
Posts: 9094
Joined: Mon Jul 28, 2008 8:21 am
Car(s): 2.0S

Wandering Timing Magical Mystery!

Post by Major_Tom »

..here's a funny one for you. I can't understand this at all.

My ignition timing wanders. Over 3000 - 6000 odd miles, it creeps from 8 btdc to the point it wont start at around 12 - 14 degrees btdc!

Everything is tight.

New distributor.

New auxiliary shaft.

It was doing this before the new parts too. It's really weird as I can't see how this can happen. Has anyone ever had or heard of anything like this?
I'm the one who leaves all those shoes in the carriageway.
B@fink
Posts: 72
Joined: Thu Mar 18, 2021 4:43 pm
Car(s): Fiat Tipo diseasel (daily driver)
Audi A8 luxobarge (high days, holidays and general waft)
Ford Capri 1.6 Laser (former daily driver, stored 15 years, rebuilt in lockdown, done, but in dire need of paint)

Re: Wandering Timing Magical Mystery!

Post by B@fink »

Yeah, that is unusual :shock:

Just to check..Are you timing it and checking it with the vacuum advance removed? It will move under vacuum as normal so would give different readings when checked.

If it’s changing and the distributor body is tight (and it’s drive gear is correct) then thinking about everything that might jiggle the timing all I can think is either, the cam belt is stretching over time changing the timing (don’t see how but that would move the timing) one of the cam toothed pulleys is moving independent of the actual cam belt (again, they shouldn’t but…) or that the internal plate that allows vacuum advance/retard to move is loose in some way so it’s flopping about and changing the timing?

Other than that I don’t see how the timing can move? And since it was doing it before new parts it makes it even more of a magical mystery to be sure!
User avatar
pbar
Posts: 7420
Joined: Thu Jun 07, 2012 6:29 pm
Car(s): Capri 2.0 Laser, frequent driver.
Location: North-West

Re: Wandering Timing Magical Mystery!

Post by pbar »

As with the previous reply, I'm also thinking of something odd with the timing belt Tom. Is that new also? If not it may be worth changing it as they're cheap enough.
Mc Tool
Donator
Donator
Posts: 2358
Joined: Sat May 17, 2014 8:34 pm
Car(s): 1980 mk3 capri 2l ohc T9 , Toyota Blade Master 3.5l V6, Paso , 850T,rd400, 900ss
Location: Invercargill New Zealand

Re: Wandering Timing Magical Mystery!

Post by Mc Tool »

End float on th aux shaft ? If it was able to move in and out it would alter spark timing . Im assuming cam timing is constant. 6 deg aint much ....enough to cause starting issues , specially if there is a bit more compression than usual . Its just about gotta be somewhere around the aux shaft or dizzy drive gears .
Sometimes I talk to myself ... and we both have a good laugh
Mr B
Donator
Donator
Posts: 635
Joined: Fri Dec 09, 2016 9:07 am
Car(s): Four 3 litre Capri's and 2 Mark 1 GXL's

Re: Wandering Timing Magical Mystery!

Post by Mr B »

Major_Tom wrote: Sat Jan 15, 2022 12:48 pm ..here's a funny one for you. I can't understand this at all.

My ignition timing wanders. Over 3000 - 6000 odd miles, it creeps from 8 btdc to the point it wont start at around 12 - 14 degrees btdc!

Everything is tight.

New distributor.

New auxiliary shaft.

It was doing this before the new parts too. It's really weird as I can't see how this can happen. Has anyone ever had or heard of anything like this?
Points and condenser or leccy ignition?
If an honest man is wrong and after demonstrating that he is wrong he either stops being wrong or stops being honest
User avatar
Bug
Posts: 3756
Joined: Sun Jan 04, 2009 3:52 pm
Car(s): Some

Re: Wandering Timing Magical Mystery!

Post by Bug »

How tight is the belt tensioner?
I had one once where the numpty before me had levered the tensioner as tight as they could, rather than letting it settle into a natural position.
It held the belt tight against the top pulley for too long and gradually would lift the belt out of the tooth and into the next one.
Given my assumption that you still have your tendency to utilise the full rev range ( ;) ) it may be that the belt is slipping?
Supercharged Nat
Donator
Donator
Posts: 5474
Joined: Mon Jul 28, 2008 4:13 pm
Car(s): Supercharged 2.1 (daily driver- when it works)

Re: Wandering Timing Magical Mystery!

Post by Supercharged Nat »

Check the dizzy end float too, they are not supposed to have much but ive seen them with 2mm or so
Image
Mc Tool
Donator
Donator
Posts: 2358
Joined: Sat May 17, 2014 8:34 pm
Car(s): 1980 mk3 capri 2l ohc T9 , Toyota Blade Master 3.5l V6, Paso , 850T,rd400, 900ss
Location: Invercargill New Zealand

Re: Wandering Timing Magical Mystery!

Post by Mc Tool »

I have a book here called "Pinto , the worst engine ever made" ,this sort of thing is probly just one of the reasons . :poke: :poke: :xd:
Sometimes I talk to myself ... and we both have a good laugh
User avatar
Major_Tom
Posts: 9094
Joined: Mon Jul 28, 2008 8:21 am
Car(s): 2.0S

Re: Wandering Timing Magical Mystery!

Post by Major_Tom »

Thanks gents, will report back when I can!
I'm the one who leaves all those shoes in the carriageway.
User avatar
Bug
Posts: 3756
Joined: Sun Jan 04, 2009 3:52 pm
Car(s): Some

Re: Wandering Timing Magical Mystery!

Post by Bug »

Major_Tom wrote: Mon Jan 17, 2022 1:34 pm Thanks gents, will report back when I can!
If you remove the belt cover (if you have one?) then slowly turn the bottom pulley using a suitable socket you may be able to see the belt riding up the top of the cam sprocket then falling back again. That's how I found mine.
That was on a GT4, wonder if there's any of those left now?
User avatar
Major_Tom
Posts: 9094
Joined: Mon Jul 28, 2008 8:21 am
Car(s): 2.0S

Re: Wandering Timing Magical Mystery!

Post by Major_Tom »

Bug wrote: Mon Jan 17, 2022 5:04 pm
Major_Tom wrote: Mon Jan 17, 2022 1:34 pm Thanks gents, will report back when I can!
If you remove the belt cover (if you have one?) then slowly turn the bottom pulley using a suitable socket you may be able to see the belt riding up the top of the cam sprocket then falling back again. That's how I found mine.
That was on a GT4, wonder if there's any of those left now?
I am thinking of a respray and adding the side decals from the GT4 actually, they look so fantastically 80s, I love it.
I'm the one who leaves all those shoes in the carriageway.
User avatar
Bug
Posts: 3756
Joined: Sun Jan 04, 2009 3:52 pm
Car(s): Some

Re: Wandering Timing Magical Mystery!

Post by Bug »

Major_Tom wrote: Tue Jan 18, 2022 11:12 am
Bug wrote: Mon Jan 17, 2022 5:04 pm
Major_Tom wrote: Mon Jan 17, 2022 1:34 pm Thanks gents, will report back when I can!
If you remove the belt cover (if you have one?) then slowly turn the bottom pulley using a suitable socket you may be able to see the belt riding up the top of the cam sprocket then falling back again. That's how I found mine.
That was on a GT4, wonder if there's any of those left now?
I am thinking of a respray and adding the side decals from the GT4 actually, they look so fantastically 80s, I love it.
Don't forget the bonnet ones too.
User avatar
Major_Tom
Posts: 9094
Joined: Mon Jul 28, 2008 8:21 am
Car(s): 2.0S

Re: Wandering Timing Magical Mystery!

Post by Major_Tom »

Wandering timing seems to have been intermittent sticking of distributor weights. Sorted now 👍 thanks for the suggestions gents.
I'm the one who leaves all those shoes in the carriageway.
User avatar
Bug
Posts: 3756
Joined: Sun Jan 04, 2009 3:52 pm
Car(s): Some

Re: Wandering Timing Magical Mystery!

Post by Bug »

Tom, are you having some kind of clear out? Answering all the replies you were given from years back?? :lol:
User avatar
Major_Tom
Posts: 9094
Joined: Mon Jul 28, 2008 8:21 am
Car(s): 2.0S

Re: Wandering Timing Magical Mystery!

Post by Major_Tom »

Getting my affairs in order Martin!
I'm the one who leaves all those shoes in the carriageway.
User avatar
Taff50ish
Donator
Donator
Posts: 694
Joined: Tue Nov 12, 2013 12:08 am
Car(s): Capri 2.8 Injection Special, every few days.
VW Tiguan for daily & boaring runs.
Triumph Speed Triple 1050, Now unfortunately gone...
Triumph 1200 Tiger XCA instead... Now also gone.
Tiger XRT instead... No, gone too...
BMW R1250RS Exec... Try this one out (old man syndrome).

Re: Wandering Timing Magical Mystery!

Post by Taff50ish »

Hey Tom,

Happy you got this sorted. Do you put a drop of oil on the felt pad under the Rotor arm every now n then? I have done this on all my cars as this lubricates the mech advance bits n bobs / cam bearing....

Basically when checking the engine oil on the Dip Sick, whip off the Dissy cover and rotor arm and put the bottom of the dip stick on the pad.... Job done...

I am always surprised by the number of people who do not seem to know about this, but it is mentioned in every Haynes manual I've ever read for Routine maintenance = 6 Months - 6000miles..... I hope this helps if this is a persistent issue?

Cheers for now,

John...

P.S. Don't do this if your engine oil is dirty / burnt!!!! Just use a bit of fresh off the bottom of a screw driver....
User avatar
Major_Tom
Posts: 9094
Joined: Mon Jul 28, 2008 8:21 am
Car(s): 2.0S

Re: Wandering Timing Magical Mystery!

Post by Major_Tom »

Taff50ish wrote: Thu Jun 30, 2022 2:06 pm Hey Tom,

Happy you got this sorted. Do you put a drop of oil on the felt pad under the Rotor arm every now n then? I have done this on all my cars as this lubricates the mech advance bits n bobs / cam bearing....

Basically when checking the engine oil on the Dip Sick, whip off the Dissy cover and rotor arm and put the bottom of the dip stick on the pad.... Job done...

I am always surprised by the number of people who do not seem to know about this, but it is mentioned in every Haynes manual I've ever read for Routine maintenance = 6 Months - 6000miles..... I hope this helps if this is a persistent issue?

Cheers for now,

John...

P.S. Don't do this if your engine oil is dirty / burnt!!!! Just use a bit of fresh off the bottom of a screw driver....
Cheers mate, yes I think that was the issue :oops: I do lubricate the dizzy, about once a year, but I guess it was not regularly enough. It's a rally distributor too, I think it gives less advance at higher revs, so perhaps spring tension is not as great and the need to lubricate more frequent :headscratch:
I'm the one who leaves all those shoes in the carriageway.
Mc Tool
Donator
Donator
Posts: 2358
Joined: Sat May 17, 2014 8:34 pm
Car(s): 1980 mk3 capri 2l ohc T9 , Toyota Blade Master 3.5l V6, Paso , 850T,rd400, 900ss
Location: Invercargill New Zealand

Re: Wandering Timing Magical Mystery!

Post by Mc Tool »

Yep , gotta admit I had a bit of a :doh: moment when the cause was revealed . 🙂🙂
Sometimes I talk to myself ... and we both have a good laugh
Post Reply