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It's been a long time since I've used timing light, much less on this motor. Can someone give me an idiot's guide to setting timing? Pics would be nice if you have any.

More info... When I got the car back the guy who had it said he set it to 12 BTDC and I had it at 8 BTDC. Ok...good. Now it idle's between 1000 - 1000 and it shakes like nobody's business. I replaced the engine mount and will be looking at the trans mount tomorrow. At idle, there aren't any odd noises but the exhaust does have what sounds like an intermittent puff of air. It doesn't seem to miss and runs great otherwise. Occasionally it smells rich.

Thanks!
 
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The easiest way to verify Cam timing and belt tension.
1)Remove the upper cover and measuring around the top from bolt tab to bolt tab get a total reading then divide by 2 and mark that spot on the cover.
This will be 12 o'clock center of the timing cover which is also 12 o'clock center of the head.
2)Remove the spark plugs and rotate the crankshaft by hand clockwise until #1 cylinder is at TDC on a compression stroke.
3)Verify TDC by being sure the timing mark on the flywheel/torque converter is aligned with 0 on the timing plate.
4)The slot in the cam sprocket should be aligned with the mark you made on the timing cover in step #1.
5)The distributor rotor should be aligned with #1 cylinder on the distributor cap.
6)Realign marks and retension belt as needed.
7)Rotate the crankshaft 2 revolutions by hand bring #1 back to TDC as in steps 2/3 and recheck mark alignment.
8)If correct you can start the car before installing all of the removed parts to verify tension is correct as long as all electrical components and vacuum lines are connected.
A properly tensioned belt will ride in the center of the cam sprocket.
If it rides to the outside the belt is too tight.
If it rides to the inside the belt is too loose







 

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Discussion Starter #3
The timing belt is hugging the outside edge of the sprocket so it's too tight. Aside from trial and error is there a specific amount of tension to put on the belt?

If everything is lined up and the flywheel timing mark is set to 0, where does the 12 BTDC come into play?
 

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If you are going to remove the covers to reset belt tension you can run the engine without the accessories and belts on to verify belt tension before re-assembling everything.
Just install the crank pully, be sure all avcuum lines and electrical connectors are connected and start the car.
Proper belt tension will be when you can twist the belt with your thumb/finger about 60 degrees but verifing the belt rides in the center is the only "true" way.
I never had success using Chryslers method with the tensioning tool so I only use that to hold the tensioner cam in place and for a primary adjustment.
Checking Cam Timing requires everything to be aligned at 0 not Ignition Timing.
Base Ignition timing is 12 degrees BTDC and that is what the controller will base its spark advance curves on.
The reason for spark advance is simple.
Electricity always moves at the same speed but engine speed does not so the point of ignition has to changed for proper combustion according to engine speed/load.
Setting/Checking Base timing is the same for all TD's.

 

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A properly tensioned belt will ride in the center of the cam sprocket.
If it rides to the outside the belt is too tight.
If it rides to the inside the belt is too loose



wow thats some useful info. every time i do a timing belt it sits on the outside edge. im only doing it with a large crecent wrench and its a tight clumsy fit. i always thought my tension was probably too low. or i messed something up while changing it..... thanks, good to know.


also yeah what is the difference between 12 degrees and 8 degrees??? someone had told me that you could adjust timing for mileage one way, or power the other way. dont know which is lower or higher degrees.
 

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A properly tensioned belt will ride in the center of the cam sprocket.
If it rides to the outside the belt is too tight.
If it rides to the inside the belt is too loose



wow thats some useful info. every time i do a timing belt it sits on the outside edge. im only doing it with a large crecent wrench and its a tight clumsy fit. i always thought my tension was probably too low. or i messed something up while changing it..... thanks, good to know.


also yeah what is the difference between 12 degrees and 8 degrees??? someone had told me that you could adjust timing for mileage one way, or power the other way. dont know which is lower or higher degrees.

As far as ignition timing, that may have worked back in the day but not with a stock computer controlled system.
The base timing is what the controller assumes is there when it makes fuel/spark advance corrections for all driving conditions/emissions/fuel economy.
Chryslers spec is 12 degrees BTDC +/- 2 degrees.
Retarding the timing will lower power so you would think that a loss of power would also result in the engine having to work harder so fuel economy would suffer.
Right now I am getting 25 mpg around town and everything is set to factory specs other than a 4 degree retard on the cam.
I have heard/read that retarding timing increases cylinder temps and advanced timing reduces cylinder temps.
I am not an engineer and it has been years since I had basic theroy training but if that is correct why do you retard ignition timing to lesson detonation which would reduce heat???
Found this link, maybe it can answer some of your questions.

HowStuffWorks "Ignition System Timing"
 

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thanks i took a pic at the wreckers of a piston that was melted. i asked someone how that happens and he said it was a a result of running lean along with running boost. not sure ant k-car wagons had turbo though this sound right???. i will post the pic soon.
 

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Detonation/Lean and Overboost Shutdown will all damage Pistons and Cylinder Heads.
Funny though that Overboost Shutdown is supposed to help protect the engine from higher boost levels and going lean in boost but it is just as damaging if you stay in the throttle or keep doing it.
 

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you say overboost shutdown? i spotted my gauge hit 15 when taking off from a right turn. is that bad??? also why cant i hit more then 10 or 11 off a straight line start? just feels like its got nothin. off a turn it feels like im going somewhere???
 

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Which car?
A 2.2L T-2 is 12 lbs of boost stock and the 2.5L T-1 is 7 lbs of boost.
The controller can read up to 14.5 lbs of boost, over that it will go into overboost shutdown where it kills fuel/ignition until the boost level is back under 14.5 lbs.
You will know if you hit overboost, it is a violent jerking of the car as the ignition/fuel are cut and if you stay in the throttle it will keep doing it over and over until something breaks.
If you hit overboost a Code 45 will be set in memory.

Boost info comes from the Map Sensor so you will have to verify that your boost gauge is accurate and seeing the same vacuum/pressure as the Map Sensor.
 

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oh boy! what you are referring to sounds like what i get on take off sometimes. usually off a turn. it will go like snot, then it dies and then goes back into boost. if i had a manual, i would say it feels like a violent shift, but mine is auto, and it really doesnt feel like a shift. more like complete shutdown, and then re animation to the max. only takes half a second to go through the stages.

oh mine is a 2.5 turbo. dont know what t-? its an 89 c/s tona auto.
 

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Common Block Engines...89-up
2.5L is a Non-Intercooled Turbo 1
Controller maintains 7 lbs of boost
The 2.2L in 89 is an Intercooled Turbo 2
Controller maintains 12 lbs of boost
The 2.2L VNT(Variable Nozzle Turbo) is a T-4(89 CSX and 90 Daytona/Lebaron/Shadow, 900 made)
The 2.2L 16 Valve DOHC is a Turbo 3.(91 Spirit R/T and 92/93 Daytona IROC R/T)
The controller maintains boost at 12 lbs.

You do not want to go over 10 lbs of boost without an intercooler.
Excessive boost without an intercooler and overboost shutdown = engine problems.
Check and see if a Code 45 is stored in memory.

Fel-Pro HG from Overboost Shutdown.
 

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went through the codes the other day after adjusting ignition timing. was at 13 or 13.5, put it dead on 12. it was running rich (puff of black on start i noticed once). no 45.
 
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