Printable Version | Subscribe | Add to Favourites
<<  1    2  >>
New Topic New Poll New Reply
Author: Subject: Ignition connundrum
mcerd1

posted on 29/1/16 at 11:05 AM Reply With Quote
What kind of tools do you have available for diagnostics?

Do you have a dial gauge and a protractor (timing disc) ?
These would let you confirm all the basics and eliminate alot of possible causes


First off you should double check the real TDC location - its worth doing just so you know that you've got a good reference for all the other timing measurements.
Assuming that you'd rather not take the engine out of the car, you'll need to get a timing disc and mount it on the crank with some kind of pointer (I just bent one out of some heavy wire and bolted it to a spare mounting hole on the block)
Then you'll need a piston stop, these are easy to make using an old spark plug hollowed out with some threaded bar through the middle - the bar should be just long enough to stop the piston a few degrees before TDC.
So you turn the engine over slowly by hand until it just touches the stop and mark the position on the timing disc, then you turn it over backwards until it just touches from the other side and mark that position too.
The true TDC it exactly half way between these marks - so remove the stop, turn the engine to this true TDC mark and zero the timing disc.

So now you can see how close the timing marks on the pulley really are. (they are almost never perfect)

If you've got a dial gauge you can the go on to check the crank angles for your valve opening/closing/max lift.....



It might seem OTT but its easy to do and the tools are pretty cheap (dial gauge + mag stand can be less than £20)
And it will let you confirm the spec of your engine, regardless of what's been done to it in the past.




[Edited on 29/1/2016 by mcerd1]





-

View User's Profile View All Posts By User U2U Member
bumpy

posted on 29/1/16 at 11:12 AM Reply With Quote
quote:
Originally posted by mcerd1
What kind of tools do you have available for diagnostics?

Do you have a dial gauge and a protractor (timing disc) ?
These would let you confirm all the basics and eliminate alot of possible causes


First off you should double check the real TDC location - its worth doing just so you know that you've got a good reference for all the other timing measurements.
Assuming that you'd rather not take the engine out of the car, you'll need to get a timing disc and mount it on the crank with some kind of pointer (I just bent one out of some heavy wire and bolted it to a spare mounting hole on the block)
Then you'll need a piston stop, these are easy to make using an old spark plug hollowed out with some threaded bar through the middle - the bar should be just long enough to stop the piston a few degrees before TDC.
So you turn the engine over slowly by hand until it just touches the stop and mark the position on the timing disc, then you turn it over backwards until it just touches from the other side and mark that position too.
The true TDC it exactly half way between these marks - so remove the stop, turn the engine to this true TDC mark and zero the timing disc.

So now you can see how close the timing marks on the pulley really are. (they are almost never perfect)

If you've got a dial gauge you can the go on to check the crank angles for your valve opening/closing/max lift.....



It might seem OTT but its easy to do and the tools are pretty cheap (dial gauge + mag stand can be less than £20)
And it will let you confirm the spec of your engine, regardless of what's been done to it in the past.


[Edited on 29/1/2016 by mcerd1]



Thanks, looks like a worthwhile option.

View User's Profile View All Posts By User U2U Member
bumpy

posted on 29/1/16 at 11:16 AM Reply With Quote
Looks like I have enough help and info to carry me into the Spring when I get the car out of storage.


The only place I am a bit short of info is preferences between buying a new Accuspark or Powerspark distributor?

Any bad experiences?

View User's Profile View All Posts By User U2U Member
mcerd1

posted on 29/1/16 at 11:31 AM Reply With Quote
Have you looked at the ones from H&H ignition

The guys are really helpful and know pinto dizzys really well





-

View User's Profile View All Posts By User U2U Member
britishtrident

posted on 29/1/16 at 12:32 PM Reply With Quote
Centrifugal advance mechanism need lubrication, from slightly bitter experience I found washing in a parts washer washes the lubrication out and makes them stick. All that is required is tiny drop of engine oil on the spindle screw under rotor arm an a drop on each of the bob weights.
The sticking tends be more common on electronics versions because the points version gets rattled a bit by the vibration and drag of the contact breaker mechanism.





[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]

View User's Profile View All Posts By User U2U Member
Chris_Xtreme

posted on 29/1/16 at 04:25 PM Reply With Quote
I think I have a ford pinto dizzy or 2 sitting about in the garage if they could be of any use to for a few beer tokens. I see the new ones are (only!) 50quid so I can see how buying new could be more of a certainty.

Also if you had a different cam and went back to a standard one, it could be that the weights were moved (what atspeed did to my pinto dizzy when I changed the cam) to adjust the advance curve, so now you are back at stock the curve is wrong.

u2u me if you are interested in the dizzys.

Chris

View User's Profile View All Posts By User U2U Member
bumpy

posted on 31/1/16 at 09:40 AM Reply With Quote
quote:
Originally posted by snapper
Idle for Pinto is usually 10-12 degrees then ramps to 34 to 36 at 3,600rpm flat after that
The vac advance is for part throttle
You should mark the pulley so you can see 8,10,12,14,16 degrees then 30,32,34,36,38
You can then set idle to something comfortable and use a strobe to view what is actually happening
Get a mate to gently increase rpm from idle noting the approximate spark advance
you should see about 10 degrees per 1000rpm to 3600rpm 36 degrees
Try this with and without vac advance
If vac is already disconected the vac advance plate may be swinging on its own thus pushing you spark advance all over the place


Something that I don't know the answer to.

When I used to set the timing on cars with points using a fag paper, the engine was static and the bob weights would be fully closed. When I set the advance at idle (say 900rpm) are the bob weights still fully closed or have they already started to open?



[Edited on 1/2/16 by bumpy]

View User's Profile View All Posts By User U2U Member
steve m

posted on 31/1/16 at 10:02 AM Reply With Quote
Has the engine always been like this? or has it just started to misbehave, if so what has happened between it was good and now
ie has the engine been pulled apart

has the cam timing been checked ? as the pinto will run with it a tooth out, albeit poorly, but enough to be able to drive

steve





Thats was probably spelt wrong, or had some grammer, that the "grammer police have to have a moan at




View User's Profile View All Posts By User U2U Member
bumpy

posted on 31/1/16 at 10:59 AM Reply With Quote
quote:
Originally posted by steve m
Has the engine always been like this? or has it just started to misbehave, if so what has happened between it was good and now
ie has the engine been pulled apart

has the cam timing been checked ? as the pinto will run with it a tooth out, albeit poorly, but enough to be able to drive

steve


So many other issues that its difficult to tell, but I never remember it accelerating particularly well, but its in a car where that's not the top priority.

View User's Profile View All Posts By User U2U Member
rusty nuts

posted on 31/1/16 at 11:19 AM Reply With Quote
If the head has been skimmed by any amount it will alter the valve timing, retarding it . The Burton power website shows how to check and set valve timing correctly ignoring any timing marks which may not be accurate. Have you checked and adjusted the valve clearances to the correct settings? As already suggested it sounds like the ignition timing is not advancing/retarding as it should probably due to a partially siezed mechanism due to standing or not being lubricated . Strip the distributor taking off the top part from the main shaft ,small circlip IIRC , polish the shaft , lubricate and reassembly making sure the two parts can rotate against each other to fully advance and retard positions. Even putting some penetrating oil down the shaft may help, there may be a felt pad under the rotor arm which should be slightly dampened with oil every service. I
View User's Profile View All Posts By User U2U Member
<<  1    2  >>
New Topic New Poll New Reply


go to top






Website design and SEO by Studio Montage

All content © 2001-16 LocostBuilders. Reproduction prohibited
Opinions expressed in public posts are those of the author and do not necessarily represent
the views of other users or any member of the LocostBuilders team.
Running XMB 1.8 Partagium [© 2002 XMB Group] on Apache under CentOS Linux
Founded, built and operated by ChrisW.