Electronic timing (Dizzy)

[BADET-4]

oooh yes, write up pls!!!!

[tassuperkart]

gooday all...

all of your suggestions are brilliant..... BUT i have found the issue and this may help others in the posses of doing up an 24 year old motor lol

the mecanical timing on this engine has neva been spot on its allways been a half a tooth out from vision so i had a thought about what damo said and played with the tensioner pully, know my cam has always had about 10 mill of play on it so after the hopeless atempts at pulling it a tooth back i put it smack bang on tdc at the crank and then pulled it a half a tooth forward on the cam witch in theory after the tensioner was pulled all the way up as hard as it would go pulled the timing half a tooth above tdc with the cam......

Know i have allways known about the spinning of the engine twice to be shore and thankyou for the sugestion good point to now lol....

So after a quick spin and then drive the car is a the machine that i was suppost to be it has gone from sitting on labour waiting....waiting....waiting then boost almost a smile.....to put the foot down pulled into seat little smile then boooost and instant wheel spin its amazing how just a tooth out can make a car drive like a bucket off doo doo


so in conclusion the issue that was found was that the timing wasn't advanced a tooth but retarded a tooth witch doesn't make sense but hay (we drive the et pulsar) so know my timing is sitting smack on 16 deg tdc ( i have it here as it runs smoother with the one deg more, old motors)

thank you all for your help and when i get time i will put a rite up on it in the near future just to save some one else the issue

OK Im having a shitload of difficulty with this issue.

Just because these engines are 25 years old does not mean that anything goes funky with them.
If it is funky then either something if fucked or an incompetent mechanic is playing out of his depth.................... in which case he, (or she) should consider another profession, slightly less technically challenging.......... perhaps a night-soil carter or a roadworks lollipop man, IF he is unable to correctly set a cam belt and tensioner to fucken spec.

The ONLY thing to get funky due to the age thing is relative cam timing after repeated head shavings.
This is due to the cambelt being a fixed length on the trailing side (variable on the tensioner side) but the distance between cam and crank centers reduces as the head is further machined. This results in the cam timing ADVANCING on these engines. No huge biggie which just tends to move the torque peak slightly lower in the rev range as well as a slight increase in compression ratio as the combustion chamber reduces in volume. All this will actually make a slightly gruntier down low motor so not such a bad thing eh??

Now, I digress, how in the name of fuck could your cam possibly have "10mm of play on it"??????????
Play from what?????????? Which direction???......... well it cant be end float, even if the thrust plate was left out on assembly so it must be rotational play.

Are you actually telling me that the belts were so loose as to allow the camshaft to move 10mm relative to the crank???????????? TEN MILLIMETERS FFS...................................... how in fucks name could something as glaringly PHAIL as that be left longer than about the all of 3 seconds it took to determine it.......?
I hope not.

How can you move anything "half a tooth"????... You cant!
The belt teeth are spaced a "tooth" apart as well.............. (out of my arse, perhaps 10mm tooth center to center???)

You either move 1 tooth (or more or less) or you dont. Move half a tooth and the belt teeth are riding up on the pulley teeth and not meshed. FAIL.

Now, a fundamental mistake for new players to E15's is that the belt tensioner is on the front side, or the "pulling" side of the belt rather than on the back side of the belt where you would expect it to be.
On the trailing side, the belt just goes around the jackshaft and on up to the cam.
This make installing the belt slightly different than with a tensioner on the back side and the front side pulling straight.

Everybody lines up the marks, just slips the belt on assuming all is well, lets the tensioner off, tightens it up assuming they had it all right.

FAIL.................... And this "mechanic" you mention fails to recognise this and discuss it with you as a possible installation error????????????????
The fact that the dizzy is as advanced as far as it goes SCREAMS at me straight away that the belt was installed incorrectly.
Mechanics? ......bah, imaginationless parts changers the vast majority of them.

10 bucks sez most dont see the marks even close. Bet they didnt see the cam wheel nine times out of 10 rotate FORWARD as the tensioner took up the slack on that side........fools!
In your case the result was retarded which is unusual. Sounds like the error was found and over compensated for. Either way, FAIL. It should NEVER have been even started in such a setting..........

The tensioner will have been released to remove the old belt and should be swung hard away against its spring and locked off in that position.

You have to install the nw belt keeping the slack OUT of the back side (keep it tight).
THEN release the tensioner nut which allows the tensioner to spring itself against the belt.
Retighten the tensioner nut to prevent it swinging while turning the crank.

You then wind the engine backwards a bit, say half a crank turn... and then wind it forwards again to TCD on the CRANK marks and have another look at the cam pulley marks.

If its within half the width of a tooth spacing or so, you can go ahead and wind the engine over a couple of times by hand to allow the belt to find its own place on the pulleys and tensioner.
Now, release the tensioner nut again and tighten the tensioner with a stubby flat blade screwstick or levering GENTLY on the pulley with a wide flat length of steel bar to get the correct belt deflection. I dont know what it is off hand, read the manual) then locking the tensioner nut off.
DONT damage that tensioner pulley by levering it like a neanderthall with screwdrivers or other sharp items. Its made of thin piss and can dent and nick easily. It will eventually damage the cam belt and that can lead to a fairly major and costly failure............

If your cam marks are out with the alignment, unlock the tensioner nut again and swing the tensioner right away against its spring and tighten the nut to keep the pesky fucker out of the way.
NB: You will need to grow some extra fingers and another hand and be able to unlock your elbow and make it rotate at least 75Deg. to do this easily on your own (Tasmanians excepted... we already have such growths). (A plus for inbreeding))!

Jump the cam pulley inside the belt in the direction it needed to go, keeping tension on the front side of the belt again, undo the tensioner nut again and let the tensioner pulley spring against the belt by itself. Give it a shove by hand to make sure its taken out ANY slack, especially on the backside of the belt run and tighten the nut again.

On the marks (or near enough)? Cool.

Wind your engine over several times in the direction it runs as mentioned before, reset the belt tension to final spec and you done.

Have I missed something Damo?

E

[Damo]

TAS, Nailed it dude!!

I don't bother using the spade slot in the tensioner, too fiddly. Just back off the locking nut, press hard on the trailing side of the belt, retighten the lock nut. This should give you a couple of mm belt slack, slide the old belt off the tensioner and cam sprocket at the same time. Line up your marks, and reinstall.

BTW, I screwed the pooch looking at the pic, that is retarded valve timing, not advanced. (Cam goes forward, dizzy goes forward to match. Cam goes backward, dizzy goes back to match.) Facepalm!

I'm thinking the '10mm' may be belt difflection, but at what pressure? If it was 10mm free play in cam movement, the fucker would have busted off all 4 exhaust valves 5 seconds into its new life.

Also, for getting tension on the belt, don't go all 'Arnie' and over tighten it, the thing will stretch and sound all weird till it fails. Check the manual, should be something like 5-10mm with 5kg of force.

Damo

[et_rider]

ok tas i dont take well to constructive Criticism...but in your case i will ya old fool.....

first im not incompetent, i have done a fucking lot of cam belts on this car and in my little pathetic life time and have found that every fucked up time i could not get the timing spot on according to the fucked up timing marks i can have the bottom pulley smack on the marks at TDC and then whack the top on and its half a tooth out according to the top mark witch i found was fixed when i pulled the tensioner on as tight as i could with a flat head screwy ...thankyou damo (you neva stop learning do you).

Second the timing was retarted becuse every one should now that you can usualy have the timing a tooth either advanced or retarted and not get piston slap were as if you have two then you will get slap...well when i retarted the timing a tooth as instructed i got piston slap as soon as it started witch means that it was retarded a tooth allready........

Third rember this, timing belts and anythng for that matter are now usualy made in sweat shops by proberly really unmaintaind machines witch means they wont be as good as they should be witch means they will be out a bit usualy witch is were the tensioner comes into it that helps with the acess play that is in.....

Fourth with the cam play do you think i would make it up??? no ya old fool that is why i have this site i can ask stupid and wierd qestions i would have thought you of all poeple would now that there is wierd shit out there and that maby you should have asked me to perahps record the play or even explained it a bit more (or slower) so if you would like me to record the play on the cam pully i was talking about please say and i will if not then who cares

ok fifth the main reason im still stumped today is the only way i was able to get it working was to make it sit a tooth in front of the timing marks as shown in the image below if i have it there i will have no issue with the timing at all the elec timing will sit smack on 15 deg or 16 in my case so tell me how the fuck this is happening, with the timing were it is this should be knocking its tits off shouldnt it?......




good day
and thankyou

[Damo]

Right, looking at your pics:

First thing would be to take off the bottom part of the dust cover which sits behind the crank pully, from there you are able to see the bottom timing mark (don't put any faith into crank timing based on the flimsy plastic timing cover marks, there is no guarantee that 'it' hasn't moved or sits correct enough to do your valve timing off!!) Also, the same applies to the crank pully, if the dowell which locates it on the crank has rounded, the marks won't line up with anything. So make sure you are using the proper timing marks pressed into the backing plates.

Next thing is, that pic shows an advance of exactly one tooth v's the correct position, all you may need to do is to retard the cam by one tooth.
And this means that the dizzy pic you have taken is not at the same cam position as this sprocket pic.


BTW, it won't be piston slap you are hearing (that is the sound the pistons make when they 'rock' onto their thrust side. A very different animal!), you will be hearing pistons contacting valves!!! very mild sound of slight ticking, followed by a terrible idle and a massive loss of power down low from bent valves!
You 'may' get away with 1 tooth retarded if the engine is 100% original (block not decked and head not shaved) any you havn't reved the thing hard, but chances of that combo is next to zero.

If I were you, I'd check my exhaust valve clearance before you do another thing. Don't bother adjusting them, just check to see if you have magicly received some tenths of a mm. If you have they are stuffed. If they are bent, the engine will need to come apart.


Damo

[tassuperkart]

Dude
You might be taking things just a bit the wrong way here. Whether you dont take criticism well or not is not my problem. I say things as i see them and I dont care how tolerant or not people are. Way it is. What you see and what you read from me, is about what you get.

Now, the "incompetent" Im referring to is the mechanic who is scratching his head on this issue you referred to..... I dont seem to recall calling you incompetent eh, chill.

I KNOW the timing was retarded originally M8, because you had to advance the crap out of the dizzy to make it run.
Your pix spoke a thousand words. Chill again. I suspect Damo is the culprit here.......old mans syndrome creeping in...his bad!

Timing belts/tensioners................. ummm what are you trying to say here thats not common knowledge????

Cam play?
Now why would I "think" you were making it up? Whatever would cause you to say such a thing??????
If it were slopping around it was slopping around.

10mm movement is 10mm movement and there can only be 2 possible directions the pulley can move, forwards and backwards. The only way it can move forwards and backwards is if the belt is loose.

Without having the car in front of me, I can only begin to speculate as to why you have the cam pulley advanced by one tooth to get ignition timing.

Is the crank pulley incorrectly located on the crank snout and just driven up against the locationg dowel rather that located correctly??
Are the timing marks correctly notched on the pulley?

Have you poked a dial guage down the #1 plug hole and VERIFIED that TDC indicated on the pulley is ACTUALLY TCD of the crank?
This is a basic check that should be done on EVERY engine, if nothing more than to just see what error there might be in the timing marks on the plastic cover.
Damo again, determined a wide discrepancy between indicated and actualy crank TDC with different fron covers. Up to 5 degrees from memory. Thats the difference between tyre frying fun and a grenaded engine....................

I seem to remember also Damo degreeing up and doing clearance measurements and finding that the valves are perilously close to clouting the pistons if the cam is a single tooth out either way. too close for him to try it out anyway.
Damo is very thorough and if he reckons its too close for comfort then it is.

With care, you can substitute a dial guage with some vernier calipers which have a dial indicator on them. Its suprisingly accurate.
A screwdriver down the plughole is too ghetto...sorry.
If that checks out then you need to do the same checks on the camshaft which is a little more tricky.
A dial guage, a degree wheel and the specifications (lift v's degrees rotation) are needed.

Ive not had a close enough look at the end of a cam to see if there is a possibility of the dissie drive "tang" being able to move around in there? But this would be the next logical step.

There is a fixed mechanical drive between the crank and the dissie and in your case, something has moved. Start at "A" and work to "Z".

There is something fundamentally very, VERY wrong there after a "recent rebuild of the old girl" and is not something as simple as a belt made in some dodgey "sweatshop" or the like, which in my view, demands immediate investigation.
You have dodged it up to get it running which for me is enough to find out what exactly was fucked up in the build/setup. Simple really. Because something is fucked up. Im not accusing you of fucking something up but its just you havent seen it thats all.

There it is.

L8r
E

[et_rider]

Right, looking at your pics:

First thing would be to take off the bottom part of the dust cover which sits behind the crank pully, from there you are able to see the bottom timing mark (don't put any faith into crank timing based on the flimsy plastic timing cover marks, there is no guarantee that 'it' hasn't moved or sits correct enough to do your valve timing off!!) Also, the same applies to the crank pully, if the dowell which locates it on the crank has rounded, the marks won't line up with anything. So make sure you are using the proper timing marks pressed into the backing plates.

Next thing is, that pic shows an advance of exactly one tooth v's the correct position, all you may need to do is to retard the cam by one tooth.
And this means that the dizzy pic you have taken is not at the same cam position as this sprocket pic.


BTW, it won't be piston slap you are hearing (that is the sound the pistons make when they 'rock' onto their thrust side. A very different animal!), you will be hearing pistons contacting valves!!! very mild sound of slight ticking, followed by a terrible idle and a massive loss of power down low from bent valves!
You 'may' get away with 1 tooth retarded if the engine is 100% original (block not decked and head not shaved) any you havn't reved the thing hard, but chances of that combo is next to zero.

If I were you, I'd check my exhaust valve clearance before you do another thing. Don't bother adjusting them, just check to see if you have magicly received some tenths of a mm. If you have they are stuffed. If they are bent, the engine will need to come apart.


Damo

thanks damo but when the timing markls was spot on is when i had the issues b4 when its this way i still cant get the dizzy timing spot on but its alot smoother and will accelerate off boost


No i just went outside and redid the whole thing i pulled the dust cover off and the harmonic balancer and lined it up spot on but inorder to get the timing spot on that way the left hand side of the belt is loose and the ritght hand side of the belt is tight so as soon as you give it a turn the cam will be half a tooth out NOW PLEASE DONT SAY THAT IS INPOSIBLE im just waiting for the car to cool down and i will take some pics for ya


just imagine the pic uptop to be half a tooth advanced instead of a full tooth



Ps: in half a tooth i mean instead of the the mark lining up here
l
--_--_--_

It will line up here
l
_--_--_

[tassuperkart]

That is perfectly normal and acceptable.
And will vary from motor to motor.
In my quad cam V6, NONE of the marks lone up any closer than that.
L8r
E

[Damo]

Right, looking at your pics:



If I were you, I'd check my exhaust valve clearance before you do another thing. Don't bother adjusting them, just check to see if you have magicly received some tenths of a mm. If you have they are stuffed. If they are bent, the engine will need to come apart.


Damo

thanks damo but when the timing markls was spot on is when i had the issues b4 when its this way i still cant get the dizzy timing spot on but its alot smoother and will accelerate off boost


No i just went outside and redid the whole thing i pulled the dust cover off and the harmonic balancer and lined it up spot on but inorder to get the timing spot on that way the left hand side of the belt is loose and the ritght hand side of the belt is tight so as soon as you give it a turn the cam will be half a tooth out NOW PLEASE DONT SAY THAT IS INPOSIBLE im just waiting for the car to cool down and i will take some pics for ya


just imagine the pic uptop to be half a tooth advanced instead of a full tooth



Ps: in half a tooth i mean instead of the the mark lining up here
l
--_--_--_

It will line up here
l
_--_--_

Not impossible at all, by its very nature, skimming the block or head are going to (as Tass has mentioned) screw with exactly where the belt is going to sit, and ultimatly the valve timing. I have had the same dilemma in the past (which turned out around 1/2 a tooth also), and have modded a sprocket to fix the 'out of whack' caused by several 5thou head shaves, and a couple of block decks.

This points in the direction of even less clearance for the exhaust valves to miss the piston crowns, especially if has leaded pistons. So it is even more critical that the valve timing isn't retarded!

Now, that being said, I still have a drama with where you needed to have the dizzy set physically to get the timing to spec.
If I were you, I would definitly check to see I had bent some ex valves. As having the dizzy set where it was in pic indicates more than half a tooth retarded.


Damo

[et_rider]

Right, looking at your pics:



If I were you, I'd check my exhaust valve clearance before you do another thing. Don't bother adjusting them, just check to see if you have magicly received some tenths of a mm. If you have they are stuffed. If they are bent, the engine will need to come apart.


Damo

thanks damo but when the timing markls was spot on is when i had the issues b4 when its this way i still cant get the dizzy timing spot on but its alot smoother and will accelerate off boost


No i just went outside and redid the whole thing i pulled the dust cover off and the harmonic balancer and lined it up spot on but inorder to get the timing spot on that way the left hand side of the belt is loose and the ritght hand side of the belt is tight so as soon as you give it a turn the cam will be half a tooth out NOW PLEASE DONT SAY THAT IS INPOSIBLE im just waiting for the car to cool down and i will take some pics for ya


just imagine the pic uptop to be half a tooth advanced instead of a full tooth



Ps: in half a tooth i mean instead of the the mark lining up here
l
--_--_--_

It will line up here
l
_--_--_

Not impossible at all, by its very nature, skimming the block or head are going to (as Tass has mentioned) screw with exactly where the belt is going to sit, and ultimatly the valve timing. I have had the same dilemma in the past (which turned out around 1/2 a tooth also), and have modded a sprocket to fix the 'out of whack' caused by several 5thou head shaves, and a couple of block decks.

This points in the direction of even less clearance for the exhaust valves to miss the piston crowns, especially if has leaded pistons. So it is even more critical that the valve timing isn't retarded!

Now, that being said, I still have a drama with where you needed to have the dizzy set physically to get the timing to spec.
If I were you, I would definitly check to see I had bent some ex valves. As having the dizzy set where it was in pic indicates more than half a tooth retarded.


Damo

Ok is there a way to check the vales with out pulling the head off as i have done the comp test and that was fine i know the engine is very nocky at idle and running, but i thought it was lifters i tryed yet again today to get the timing right but can only seem to get it eiter one tooth advanced or or retarted its very hard to get it rite (witch now seems to be the half a tooth trick) does this mean that being the fact that the head has oviasly been shaved some what...would it be best to have it half a tooth ahead as aposs to behind....

but even then with that when i had it there the timing still had to be of the scale in order to rev b4 boosting if i set it up at 15 then it will boost and no revs.....the timing light im using is just a cheapo one no flashy dials or anything....


i also now what you mean damo and tas with pulling the harmnic balancer of and doing it that way the dowl was very rounded and im supriced i havent muched the engine as is


thankyou again guys i will be trying again after tafe tomorow, is there any trick i should try when doing it or just go for as posibly close to the marks as i can

thankyou again
matt

[et_rider]

That is perfectly normal and acceptable.
And will vary from motor to motor.
In my quad cam V6, NONE of the marks lone up any closer than that.
L8r
E

Should i maby look at getting the adjustable cam gear would this help out the issue at all

[Damo]

The head won't need to come off to find out wether the exhaust valves are bent. Pull the rocker cover off and compare the exhaust valve clearance to the inlet. Factory spec is around .22mm cold upto .28 hot for both, if your clearence is over .4mm for the exhaust valves while the inlet are within .05mm of spec, you have bent your exhaust valves.

As for setting the timing belt, you won't be able to adjust where the belt ends up v's TDC, but you will be able to move the cam forward or backward a tooth. Go for advancing the valve timing (tooth forward of timing mark) rather than retarded.



NOTE: Do not try this if you are unsure of what you are doing!! Get it wrong and you will need to pull the engine appart to change broken bits!!!!!!!!!!


If you must have the valve timing retarded a 1/2 tooth to get it to run at all, I'd recommend that you set the engine up the way you want with the belt and tensioner factory spec tight, wind the engine over by hand till your at around 5-7deg BTDC, loosten off the locking nut on cylinder #1 exhaust valve, screw the adjuster in till there is zero valve clearence, then note down EXACTLY how many turns of the adjuster screw it takes for the valve to contact the piston. You need at least 60thou/ 1.5mm clearance to avoid contact with a 'working' set of valve springs, or out to probably 2mm with the old stockers. The pitch on the adjuster is 1mm, so 1 full turn is 1mm clearance.
Make sure to back the adjuster all the way off before you go and turn the engine over on the starter again!!!!!


This is how I checked my clearances with the new cam, and is the reason why the valve timing on mine IS where it is.



Damo

[et_rider]

The head won't need to come off to find out wether the exhaust valves are bent. Pull the rocker cover off and compare the exhaust valve clearance to the inlet. Factory spec is around .22mm cold upto .28 hot for both, if your clearence is over .4mm for the exhaust valves while the inlet are within .05mm of spec, you have bent your exhaust valves.

As for setting the timing belt, you won't be able to adjust where the belt ends up v's TDC, but you will be able to move the cam forward or backward a tooth. Go for advancing the valve timing (tooth forward of timing mark) rather than retarded.



NOTE: Do not try this if you are unsure of what you are doing!! Get it wrong and you will need to pull the engine appart to change broken bits!!!!!!!!!!


If you must have the valve timing retarded a 1/2 tooth to get it to run at all, I'd recommend that you set the engine up the way you want with the belt and tensioner factory spec tight, wind the engine over by hand till your at around 5-7deg BTDC, loosten off the locking nut on cylinder #1 exhaust valve, screw the adjuster in till there is zero valve clearence, then note down EXACTLY how many turns of the adjuster screw it takes for the valve to contact the piston. You need at least 60thou/ 1.5mm clearance to avoid contact with a 'working' set of valve springs, or out to probably 2mm with the old stockers. The pitch on the adjuster is 1mm, so 1 full turn is 1mm clearance.
Make sure to back the adjuster all the way off before you go and turn the engine over on the starter again!!!!!


This is how I checked my clearances with the new cam, and is the reason why the valve timing on mine IS where it is.



Damo

Ok fiddled more today and i have got the timing spot its still a half a tooth advanced but the belt its tight either side now were as b4 it was tight on the pulling side and loos on the trailing side witch i cant imagine would be any good on reving down....but the elec timing still needs to be off the scale to read right......witch (wacks head a little hard) if the harmonic balancer has play then the timing wont read corect will it?....bloody idiot why didnt i think of that....well in that case is there away to check the elec timing with out a light, normaly (to evens distgust lol) i will just do it by sound and feel, but this time i wanted to get it spot on

thankyou matthew

[et_rider]

ok so what your saying there damo is that there is a possible way to bring the timing one may two teeth in front with out nock just by adjusting the exust valves up a bit

is that what e was saying how you were trying to see if it could be done?

[tassuperkart]

No! Hes NOT saying that at all.

Look M8, you cannot fudge it one way or other. You get what you get. Its called "production tolerances".
In fact, NOBODY can get the marks to line up exactly OK.

You just have to get them to whichever way its closest. Way it is.

Damo has quite clearly stated that if the marks are exactly half a tooth either way then go for the ADVANCED setting which will keep your valves away from pistons.

I have given you a blow by blow description of fitting and timing up and tensioning the cam belt.
Looking at your pix, that cam wheel is EXACTLY 1 tooth out (advanced). Ive never even seen one that close to correct! So what is all this bollocks about half a tooth here and there, loose belts on one side and other blarney???

If you still have ignition timing issues then something else is WRONG.
Ive given you a step by step concerning that.

However, how, FFS can you ever KNOW if you have timing issues without knowing EXACTLY where the actual ignition timing is eh??
You dont have a timing light.
You cannot set anywhere near close the ignition timing of slack-tuned low compression engine by ear. Anything 10 degrees either way of correct will sound good.

L8r
E