Euro twin dizzy timing ?
10-15-2011, 11:13 AM
#1
Three Wheelin'
Thread Starter
Euro twin dizzy timing ?
I have finally got my car ready to start after engine pull/refresh due to timing belt break. The car cranks but does not start.
Checked everything and the notches in the cam pulleys line up while the rotors point at their notches and the car is at TDC. However, I noticed that the previous owner had red marks on the cam pulleys that are 180deg out????? Just want to make sure I am not doing something opposite of what should be done.
I also noticed that I am getting puffs of fuel smelling vapor coming back through the throttle body and MAF while cranking.
Also, just to confirm, TDC on the #1 cyl can be determined by a puff of air blowing out when the spark plug is removed when turning the crank? Want to make sure I didn't set the belt 180 deg out.
Checked everything and the notches in the cam pulleys line up while the rotors point at their notches and the car is at TDC. However, I noticed that the previous owner had red marks on the cam pulleys that are 180deg out????? Just want to make sure I am not doing something opposite of what should be done.
I also noticed that I am getting puffs of fuel smelling vapor coming back through the throttle body and MAF while cranking.
Also, just to confirm, TDC on the #1 cyl can be determined by a puff of air blowing out when the spark plug is removed when turning the crank? Want to make sure I didn't set the belt 180 deg out.
10-15-2011, 11:30 AM
#2
Nordschleife Master
Make sure the rotor points at the wire for the #1 plug when the cam notches are aligned.
It's a classic mistake to put the timing 180 off. ("Classic" meaning BTDT.)
It's a classic mistake to put the timing 180 off. ("Classic" meaning BTDT.)
10-15-2011, 11:45 AM
#4
928 Collector
Rennlist Member
Rennlist Member
I don't see any question about the twin-dizzies though ... are you sure you have those properly lined-up? Mine on my 85 euro had such an old belt (elastic band, rather) that it was basically operating on blessings.
10-15-2011, 01:47 PM
#5
Three Wheelin'
Thread Starter
Yes, it is a twin dizzy. Yes, the rotor points to #1 plug wire at TDC. That is actually where the notch is located on the housing. The twin dizzy housing has 2 notches in it which is where the rotors should point when lined up at TDC and all is lined up.
10-15-2011, 01:59 PM
#6
Rennlist Member
Well, doesn't sound right that you are getting fuel/air back through the MAF... I assume you have checked for compression on all cyl after that cambelt breakage ?
You have the spark synch'd with TDC on #1 but you need to confirm that the TDC is on the compression stroke, not the exhaust one - 180 on the cam would be 360 deg on the crank, so it is possible that timing is out, but I don't think that is possible with the cam wheels keyed to the camshaft ?
You have the spark synch'd with TDC on #1 but you need to confirm that the TDC is on the compression stroke, not the exhaust one - 180 on the cam would be 360 deg on the crank, so it is possible that timing is out, but I don't think that is possible with the cam wheels keyed to the camshaft ?
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10-15-2011, 02:38 PM
#8
Three Wheelin'
Thread Starter
Pics of balancer and twin dizzy at TDC. Didn't check compression yet, but after pulling the motor, I did a leakdown and it was less than 3% on all. Also looked over everything with a boroscope.
10-15-2011, 02:43 PM
#9
Inventor
Rennlist Member
Rennlist Member
Balancer is backwards...
10-15-2011, 03:29 PM
#10
Three Wheelin'
Thread Starter
Guess I should change the title of the thread to "how to change your TB twice after 0 miles"....
Looking at it even if it was flipped, it might be out 2 teeth??
Looking at it even if it was flipped, it might be out 2 teeth??
10-15-2011, 03:43 PM
#11
Team Owner
Warning...it will be out more than 2 teeth
So how to proceed??
OK first remove the timing belt covers,
then remove the damper without turning anything figure out where the crank keyway is
Your wanting to return the crank to the 45 degree BTDC so to do that the keyway should be pointing at the driverside fender or the 3 O clock position.
this will reduce the chances of the valves hitting .
So continuing, refit the damper and turn the crank till the keyway is in this approximate position leave the belt on till this is done.
Once you have the crank keyway facing the 3 O clock position ( this is while your facing the engine) then remove the damper and turn it around,
then remove the belt and then put each cam at about 3 teeth before the respective line up marks ,
refit the belt turn the crank to TDC then check that the cams are timed ,
this should be close to on the money if not then remove the belt and adjust,
Reassemble the engine and set the timing belt tension with the engine set at TDC,
turn over a few times to verify that the engine turns smoothly and the belt tension is repeating,
you want about 1/2 way on the kempf tool
So how to proceed??
OK first remove the timing belt covers,
then remove the damper without turning anything figure out where the crank keyway is
Your wanting to return the crank to the 45 degree BTDC so to do that the keyway should be pointing at the driverside fender or the 3 O clock position.
this will reduce the chances of the valves hitting .
So continuing, refit the damper and turn the crank till the keyway is in this approximate position leave the belt on till this is done.
Once you have the crank keyway facing the 3 O clock position ( this is while your facing the engine) then remove the damper and turn it around,
then remove the belt and then put each cam at about 3 teeth before the respective line up marks ,
refit the belt turn the crank to TDC then check that the cams are timed ,
this should be close to on the money if not then remove the belt and adjust,
Reassemble the engine and set the timing belt tension with the engine set at TDC,
turn over a few times to verify that the engine turns smoothly and the belt tension is repeating,
you want about 1/2 way on the kempf tool
10-15-2011, 06:37 PM
#12
Three Wheelin'
Thread Starter
I just decided to pull it all off and start over. My car is non interference. My question is how to confirm that the car is at the TDC. I know that it takes 2 revolutions of the marks on the balancer, but how do you which revolution is TDC of #1 ? I have the cam sprockets lined up, but want to make 100% sure I am on the correct crank revolution. I don't want to do the belt a third time...
10-15-2011, 07:57 PM
#13
Nordschleife Master
TDC happens every revolution. It is the "Top Dead Center" of the piston meaning the piston is as high up in the cylinder as it can get.
You need to know when TDC happens on the compression stroke. That's determined by the cam position and is (conveniently) when the cam notches line up. At that point the distributor rotor needs to be pointing at the plug wire for the #1 cylinder.
You need to know when TDC happens on the compression stroke. That's determined by the cam position and is (conveniently) when the cam notches line up. At that point the distributor rotor needs to be pointing at the plug wire for the #1 cylinder.
10-15-2011, 08:16 PM
#14
Three Wheelin'
Thread Starter
I just want to make sure everything is lined up correctly. Without the belt on, can I just turn the crank to TDC regardless of revolution and then install the belt with the cam sprockets lined up on the notches?
I guess my question is: Is the crank always a 1:1 TDC by itself and only when it is attached to the cams by the belt do you have to go 2 revolutions to get back to the compression stroke? Then you set the dizzy based on the TDC as well as the index marks on the cam sprockets when they are all 3 lined up? At that point you install the dizzy with the rotors facing the index marks on the body where the rotor will be pointing at the #1 plug wire? If you pass the marks when turning by hand, then you must go 2 full revolutions to install the dizzy?
I think it is a lot more simple that I am imagining it to be.
I guess my question is: Is the crank always a 1:1 TDC by itself and only when it is attached to the cams by the belt do you have to go 2 revolutions to get back to the compression stroke? Then you set the dizzy based on the TDC as well as the index marks on the cam sprockets when they are all 3 lined up? At that point you install the dizzy with the rotors facing the index marks on the body where the rotor will be pointing at the #1 plug wire? If you pass the marks when turning by hand, then you must go 2 full revolutions to install the dizzy?
I think it is a lot more simple that I am imagining it to be.
10-15-2011, 08:53 PM
#15
Inventor
Rennlist Member
Rennlist Member
0|T can either be #1 or #6. Take out the spark plug on #1 and see if the piston is at the top.
Do you have one of the early '84s w/'83 (lower compression) pistons?
Do you have one of the early '84s w/'83 (lower compression) pistons?