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-   -   TIMING ISSUES! Switched pulleys, and the timing marks are totally different? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/timing-issues-switched-pulleys-timing-marks-totally-different-973214/)

Osirus9 10-13-11 09:45 PM

TIMING ISSUES! Switched pulleys, and the timing marks are totally different?
 
2 Attachment(s)
So I swapped motors, and the new motor has an s5 front cover, so I swapped it with my s4 one along with the pulley and the CAS.

this is the old pulley on the new motor. Note the yellow timing mark is lined up with the front cover, and the orange mark is ~15 degrees toward the CAS
Attachment 717472

this is the new pulley on the old motor. Note the yellow timing mark is lined up with the front cover, but the orange timing mark is ON THE OTHER SIDE ~15 toward the water pump
Attachment 717473

I am trying to set the timing, and I have it hooked up to my haltech. so at -5 the trigger angle should be about 65, and that's what it used to be set at and it worked perfectly.

NOW if I set the trigger angle to 65 it runs like crap. It actually runs very well with the angle set to 25. This setting causes the front cover to point about ~20 on the OTHER side of the orange timing mark. almost to where the belt is on the first picture.

does anybody know the timing differences between these 2 different kinds of pulleys? How can I set my timing with this pulley?

I really don't want to just swap on the pulley that came with the motor because mine is powdercoated and I don't want to risk having the torrington bearing slip off.

is it safe to just set the timing to where the car sounds good?

Osirus9 10-13-11 09:50 PM

Also, I have a coolant leak coming from somewhere around the back of the motor. I can't see it coming from the TB coolant line on the top of the rear iron, or from either of the turbo coolant lines, or from under the LIM.

it almost looks like it's coming from the bottom clutch inspection hole? Is there anywhere on the back of the motor that coolant could be coming from? I thought the rear seal was only for oil...

RotaryEvolution 10-13-11 09:59 PM

use the original pulley that came off the motor. if you're intent on using the powder coated pulley, fill in the marks and translate them from the old pulley.

Osirus9 10-13-11 10:03 PM

crap, sorry I actually have one more problem lol.

it sort of goes with the coolant leaking... There is a little white smoke coming from the (3in RB rev II, so no cats or restrictions) exhaust. it's noticeable at idle, and it gets worse when I give it gas, but it's not as bad as when I had blown coolant seals and I could fill the block with smoke in like 30 seconds. Maybe it isn't a big deal, especially since I replaced the front cover and there could be cleaning agents still in the intake? I have let it idle for about a half hour or maybe more and it seems to remain constant all the time.

I also took a look at the coolant filler neck cap and I don't see any bubbles in there...

I guess I'm looking for reassurance because I'm super paranoid about the engine's condition.

Osirus9 10-13-11 10:05 PM


Originally Posted by Karack (Post 10823502)
use the original pulley that came off the motor. if you're intent on using the powder coated pulley, fill in the marks and translate them from the old pulley.

I COULD do that, but I don't want to risk smashing the torrington bearing when I take the front pulley bolt off. That solution will be my last resort.

Does anybody know anything more about this mysterious mismatched pulley problem? Why do multiple pulleys fit if the timing marks are different?:scratch:

RotaryEvolution 10-13-11 10:09 PM


Originally Posted by Osirus9 (Post 10823511)
I COULD do that, but I don't want to risk smashing the torrington bearing when I take the front pulley bolt off. That solution will be my last resort.

Does anybody know anything more about this mysterious mismatched pulley problem? Why do multiple pulleys fit if the timing marks are different?:scratch:

who said you have to remove the crank bolt? put the original pulley on, set it to leading TDC, remove it, put on your painted pulley and stamp it with a hammer and chisel, remove, switch to trailing tdc, rinse and repeat.

gilmers don't have any timing marks whatsoever so you have to do a process like that.

misterstyx69 10-13-11 10:48 PM

One an S4 Pulley and one an S5 pulley?????
Been there..done that.
screwed around the timing when setting the Haltech.
use the pulley that the engine had on it.(you can always powdercoat it later).
you can't use the s4 on an s5 or reverse.

bumpstart 10-13-11 11:40 PM

bollocks
i have swapped them ( s4 and s5 ) around many times,, they are the same pulley
i have even reverted timing covers s4 to s5 and even 12a and found no issues here

the 4 way set of holes for the pulley to the hub can allow the pulley to bolt on in only one position
( one of the holes is deliberately offset to make this so )

the first picture shows a pulley with a homemade stamp , it is clearly very wrong cause it has a red mark already past tdc

when turning the engine clockwise a real mazda pulley will show yellow first ( 5 ATDC ),, then red ( 20 ATDC )
ie -the red mark is always over to the manifold side when yellow is near vertical
so how is it the first pic shows red then yellow ?
it is clearly bodged and marked incorrectly , even the chisel mark does not look factory
i bet this happened when it was mirrored off a correct pulley ,, or that a previous owner may have been trying to mark a 10 BTDC mark
( cause some worked engines dont idle long when held to 5 ADTC for timing checks )

-------------------

you can get the mark nearly right by putting the bite from the flywheel down the inlet side
or by putting the wings of the auto balance down the spark side
when you do this,, one of the 4 bolt holes will be be near vertical
,, underneath the hub,,the hub keyway is at 270 degrees
now put the pulley onto the hub so the mark is upright and near the pin
,, you should find it will only bolt up with this orientation

when it is bolted on,, you may need to move the engine very slightly to line up the mark and pulley
it does not matter ,, ( twas due to your guestimation where the flywheel bites lay )
but when the mark and pin line up,, this will be 5 ATDC ,, and the 20 ADTC mark should still be on the manifold side of the pin

Osirus9 10-14-11 09:54 AM

ok, so I took my old pulley and my new pulley off their respective engines and compared them. The marks may indeed have been just colored wrong like you suggested bumpstart.

I don't really understand what you mean by flywheel bite though... is there a reference picture or something somewhere? what's an auto balance?

I put both pulleys facing the same direction and bolted them together and copied the marks from my old pulley. They were actually similar if you switched leading and trailing marks...

Anyway, I put the pulley back on with the front cover pointer at the yellow mark with the CAS gear lined up. set the trigger angle to 65, and... it ran like ass.

according to the timing light, my timing is spot on, but the engine stumbles and can barely make 2500rpms. I screwed with the trigger angle, and it now likes ~35 instead of ~25, but that makes the marks show up somewhere under the water pump. I drove the car around the block like that and it seemed just fine. WTF is going on? Why does my car not want to run with the pulley lined up?

Also, I sometimes can't get the timing light to fire from the T1 coil wire, and only that one. Does that mean my trailing coil is dying? Could that affect this somehow?

bumpstart 10-14-11 10:45 AM

it is a bit of a worry
,, i went back today and checked all the timing covers against a set square and a marked board
all the timing covers ( 12a, s4 13bt , s5 13bt ) had the pin in the same position

so i went an pulled a box of around 20 hubs and pulleys

lined them all up with the keyways
,, 12a/ early 13b is easy to ID cause of the locating rivet and fawn pulley
late s3 12a and the RESI ( GSL-SE ) 13b have the black pulley with no locating rivet and four equal bolts ( so will fit on 4 ways )
and FC hubs easy to id cause they have a stamped dot id on the hub itself
( to line up the PS and AC pullies due to assym four bolt pattern )

now,, what i DID find here was interesting
out of around 10 ,,, 2 where odd
now,, the pullies themselves bolted up ( with assym bolt pattern ) to either hub
BUT
the did indeed shift the timing mark position
lining these hubs up ( hubs with the stamped dot ) all by the leading timing mark showed a shift in the keyway slot akin to around 10 -15 degrees ( approx )

now,, knowing that mostly these FC pullies came from about relatively even batches of s4 and s5 TURBO engines
and that there was the very occasional s4 NA engine
i pulled the following conclusion
- s4 NA ( n326/327 )engines have the odd spark locations
( speaking world delivered FC engines and not specifically US domestic engines )
aussie/jap/world outside of USA got the turbo engine n318
( with spark locations same to the s5 engines NA and turbo )

from what i can see,, these odd pullies may well have been n326/7 pullies ,, and the location of the timing marks is revised to suit the TDC position
( TDC defined as the middle distance between the spark plugs rather than minimum displacement position )
so,, to revise my above post
,, s4T ( n318 ) and s5NA( n350 )and s5T( n370 )
all seem to share identical pullies / hub combos

exceptions may be n325/7 and n332 ( US s4 turbo )




BTW the hubs for all other pullies line up
and produce the expected 5 ATDC ( black pulley ) or TDC ( fawn pulley )
[ all these are easy to id as hubs have the key at 270 when the two side bolts are also at 90 and 270 ]
i suppose things are not so obvious unless you can mass a dozen or more various pulleys at one go


so,, what does that mean for the OP?
well,, that s5 hub may well be different to the s4 one,, but which one to use >?
my description above about the "bite" is about the flat section on the back of the flywheel provided for the balance
,, you see it from the clutch inspection plate
( if you have auto,, or light fly ,, you instead have a mass with wings, that will lay on the opposite side of the engine )


am suspecting that it is not as simple as just swapping the pulley over on the hubs
as when missmatched
,, neither combo will show a true 5 adtc
if the engines are out,, tis a simple matter to rest it on the flywheel and simply swap hubs with no torrington risk

it may well be what you have to do to sort it , beyond doing the apex seal visible in rotor 2 trick and remarking the pulley
IE
put the flywheel to the known position
rotate it back slightly till apex seal visible in trailing 2 hole ,, mark pulley lightly
rotate forwards till same apex seal visible in rotor 2 leading hole ,, mark pulley lightly
TDC lays smack in the middle of the two marks ,, mark heavily with chisel and yellow marker

Osirus9 10-14-11 11:19 AM

oook, so basically, I have 2 pulleys that are not interchangeable...

I have the stock flywheel on there, so if I remove the inspection plate on the passenger/turbo side I should rotate the flywheel until the weighted part is facing me ie 90 degrees?

Then take out the trailing 2 plug and rotate the engine Counter clock wise until I see an apex seal.
mark the pulley with a marker at the front cover pointer.
then rotate the motor clockwise until I can see that apex seal in the Leading 2 hole.

the yellow -5 TDC mark is between these 2 marks?

also, is there a way to find the -20 TDC mark by doing something similar?

Thanks for your help.

GregW 10-14-11 11:34 AM

Wow, utter confusion here.

Pully and hub should be treated as a matched pair. If you mix pullys and hubs you cant gaurantee accurate timing marks.

Take a matched pair, spin to leading or trailing, pull off matched pair, put on random hub with super sweet pully, make a mark on new super sweet pully. Repeat for leading/trailing.

Store nasty old matched pair in bottom drawer of toolbox after sticking tape on pully that says "DONT THROW AWAY"

Do a search, there is volumes about it on this site.

RXSpeed16 10-14-11 11:57 AM

I know it's been discussed, but making a custom set of timing marks for each engine would be a manufacturing nightmare. You'd have to manually mark each one after the engine is assembled rather than just drilling all the holes in the same place and having a machine mark the same spot on the pulley. Bumpstart's trial shows the variation between certain pulleys which could correlate to different spark plug locations. Maybe there is a different part number for the USDM s4 turbo pulleys?

RotaryEvolution 10-14-11 05:18 PM

there is no magic method of finding an accurate TDC with the engine assembled(the plug hole method is also a rough estimate since the plug holes are not located in exact dimensions top to bottom and bottom to top, there are also different splits depending on the housings). assume the original pulley was correct and transfer the marks. it takes 5 minutes.

bumpstart 10-14-11 09:56 PM


I have the stock flywheel on there, so if I remove the inspection plate on the passenger/turbo side I should rotate the flywheel until the weighted part is facing me ie 90 degrees?

bumpstart wrote:

the keyway is at 9 oclock ( view from front ) [ when timing l1 mark is up ]


if you have a standard flywheel on,, ( view from rear ) then the bite missing from the back ring will be pointing at the exhaust at 3 oclock
if you have an auto counterweight ,, then the bumps will at 9 oclock ( view from rear ) down the spark side
( look down inspection cover )

Maybe there is a different part number for the USDM s4 turbo pulleys?
i agree that none of these hubs or pullies are custom marked when the engine is made and that they are mass produced


the FC pullies themselves swap readily ( the assym pattern is repeated )
,, it is the hub that is odd
,, most hubs have two of the four bolt holes at 90 and 270 when the hub key-way is at 270
these odd hubs have more like 255 and 75 degree drilled holes

the pics-
http://img835.imageshack.us/img835/1503/pic1015051.jpg

http://img12.imageshack.us/img12/8784/pic1015053.jpg
12a/ early 13b hub ( alum rivet locates the pulley )
the keyway in this picture is nearly vertical,, if you place a straight edge across the pulley bolt holes ( vertical ) it will cover the keyway

http://img819.imageshack.us/img819/9532/pic1015052.jpg
the majority of FC pullies are this,, note the orientation of the hub key with the bolt holes
straight edge across the holes will cover/ align with the keyway

http://img18.imageshack.us/img18/3705/pic1015054.jpg
and so these ones are ( when keyway is at 270 degrees ) roughly 75 and 255 degrees
a straight edge here will miss the keyway

http://img513.imageshack.us/img513/9589/pic1014046.jpg

http://img4.imageshack.us/img4/204/pic1014047.jpg

http://img824.imageshack.us/img824/961/pic1014048.jpg
curiously this s5 cover has casting for two timing pins ,, looks like they intended some of these for a larger main pulley

bumpstart 10-14-11 10:05 PM

PS

for the OP,, between the two engines the CAS is stabbed differently
,, there is every reason why one engine likes the trigger angle to be 65 and the other not
-- irrespective of your TDC /pulley issues

while i see the dilema in your timing issues,, i would keep the pulley that came with each engine,, on each engine
you can try the apex seal /rotor 2 trick to remark a TDC
but ultimately you may need to use a custom trigger angle selection to suit how the CAS is dropped in on the new engine
you MUST use whatever number is required to get the light to show the timing mark at the pin when timing is locked to 5 ATDC or zero ( depending on which mark you use )

with haltechs you MUST keep this number above 45
this is so the ECU has a forward window in which to adjust the timing
,, if the number is 25 then the ecu will be incapable of advancing the ignition more than 25 degrees

if that is the case,, then you select one trigger tooth number less ,, and add 30 to the trigger angle

ie,, 11 tooth - 25 degrees is the same as 10 tooth - 55 degrees, and 9 tooth -85 degrees

SpeedOfLife 10-15-11 08:00 AM


Originally Posted by Osirus9 (Post 10823485)
does anybody know the timing differences between these 2 different kinds of pulleys? How can I set my timing with this pulley?

I really don't want to just swap on the pulley that came with the motor because mine is powdercoated and I don't want to risk having the torrington bearing slip off.

is it safe to just set the timing to where the car sounds good?

I don't know how one might identify a loose pulley in a box, don't bother, and no. hold the clutch pedal down with a stick and use a matching hub and pulley (either the original two or the pair that came off whatever motor you sacrificed, buuuuut the original is the best bet). holding the clutch pedal down keeps the eshaft pushed forward so the bearing can't drop. I ran into this problem when I built my motor, my turbo would glow, I was boosting at light throttle, and it ran like total shit. swapping back to the original pulley and hub then setting the timing solved the problem immediately (IIRC I was using the original hub, but the pulley from my donor motor. don't do that).

Osirus9 10-15-11 11:17 AM

arg, I guess I have no choice but to remove the hub and use the pulley/hub from the new motor :/

Unfortunately I won't have time to try that until Thursday... le sigh

Thanks for all the info guys

arghx 10-15-11 11:50 AM

When I rebuilt my motor I didn't trust the pulley and hub combo. So I bought a brand new pulley and hub set from Mazda for an 88 T2 for around 180 dollars. I set the timing according to the marks and have had zero problems. I am using a power fc

RotaryEvolution 10-16-11 02:15 PM

well, the most accurate method seems to be setting the front e-shaft keyway to exactly the 9 oclock position at which point the leading mark on the hub/pulley combo should match up to the pointer. usually it's pretty evident if the pulley/hub you grabbed isn't a match as 15 degrees is pretty noticably off.

i just don't understand why they made different sets, the timing variations aren't an issue with the shaft position as the timing marks on the front cover are all the same.

it's just a total pita to do all of this with the engine in the car and it's just lovely when you get someone with an engine that has the incorrect pulley set installed, rebuilt by someone who grabbed parts out of a box of parts without any regard. what's worse is the 12As with the equal bolt holes so the timing can be off in 90 degree increments.

Osirus9 10-21-11 09:33 AM

2 Attachment(s)
Alright, So I decided to just swap pulleys and hubs back to the motors that they came from.

First thing I did was put the car in gear and get the front hub bolt started. I had to put the car in 5th, because I was actually moving the whole car WITH the hand brake on when it was in 1st!

The second it came loose (maybe half a turn) I went and shoved a 2x4 on the clutch pedal to hold it all the way down. I ten removed the bolt and the hub.

These are pic of the two hubs together facing the same way.

Attachment 717477

Attachment 717478

Note that the timing marks I made are not perfect even though I had the pulleys off the car. apparently its very difficult to make the marks line up... So I wouldn't advise anybody to try that method
Anyway, They look about the same. They're only a few degrees off in anything.

So I said, what the hell and swapped them anyway. lined up the yellow mark with the front cover pointer, checked that the CAS was lined up with it's pointer by removing it and taking a look. it was perfectly aligned, so I thought I was wasting my time, but proceeded regardless.

upon tightening everything back down and starting the car I hooked up the timing light and what do I find? THE TIMING IS WAY THE FUCK OFF AGAIN. except this time in the right direction, with the marks about 40 degrees toward the CAS. I didn't have my laptop with me to adjust the trigger angle, but setting it to 65 from 25 should move it back to just about lined up. I will post results.

I'd have a pic of the timing, but I couldn't get the camera to pick it up properly...

MORAL: KEEP THE HUB/PULLEY that came with your engine. They are different sometimes, and it is very hard to tell if they are!

Osirus9 10-21-11 09:34 AM

I also found my coolant leak, it was just the heater hose needed to be tightened.

bumpstart 10-21-11 07:07 PM


upon tightening everything back down and starting the car I hooked up the timing light and what do I find? THE TIMING IS WAY THE FUCK OFF AGAIN. except this time in the right direction, with the marks about 40 degrees toward the CAS. I didn't have my laptop with me to adjust the trigger angle, but setting it to 65 from 25 should move it back to just about lined up. I will post results.
if you understood what i wrote above about the trigger tooth and trigger ref angle setup for haltechs
then you will understand why you cannot use a trigger angle lesser than your expected timing advance window

if the number you need will be 20
but the advance window you require is going to be potentially closer to 35-40
then you select 1 trigger tooth less ,, and add 30 to the trigger angle
ie 11 teeth 20
is same as 10 tooth 50 degrees
or 9 tooth 80 degrees

50 and 80 degree windows being sufficient for the ecu to deal with timing advance after seeing the trigger tooth
( note some versions of e6 will not allow certain combinations of tooth count/ angle )
ie,, the ecu sees the home trigger,, starts counting the Ne ( angle indicating ) teeth ,, counts out the 9 and anticipates that that TDC is 80 degrees away
and so can subtract the timing lead in from the look up table,, subtract the dwell period, and initiate coil charge in anticipation of the spark event at the right time

NOTE

this messing with the ecu setup is all due to the dropped in CAS position
restabbing it 30 degrees more advanced will also put it back near that original set of numbers that worked on the other engine

Osirus9 10-22-11 10:06 AM

nevermind... it didnt work. The trigger angle has to be set to 95 in order to get the timing marks to line up now. and the car runs like shit. it still wants the trigger angle to be set to something like 30 for it to run decently.

so if I stab the CAS as per the FSM, but I need to set the trigger angle to an absurd number I can change the trigger tooth?

mine is set to 11, but I didnt know what that setting did so I left it alone. if I change that to 10 that would put my trigger angle to 65 which is where I want it. if the trigger angle is too high or too low will that affect how the car runs at idle/free rev/cruise? I haven't tried to give it more than 40% gas yet for obvious reasons...

Osirus9 10-22-11 10:32 AM

I actually just got off the phone with my tuner and he said DO NOT change the trigger tooth. the trigger tooth corresponds to the actual teeth in the CAS, and changing it is more or less fooling the ECU into doing something instead of having it set up correctly.

He suggested I jumped a tooth while installing the CAS, as I'm off by about one tooth (95-30 = 65 which is just where it should be). He also agreed that the Haltech doesnt operate properly if the trigger angle is set below 45 or above 80, which could be why my car runs like diarrhea.

I'm gonna go mess with it some more... who knew setting the timing could be this hard...


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