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Old 12-14-2015, 04:02 PM   #1
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Default Help request: Crank pulley bolts sheared at speed. Now she won't start.

I just need a little bit of direction if you can help.

I have a turbo'ed NA w/ a 1.8L transplant purchased a couple of months ago. A week ago, the crank pulley bolts sheared off at highway speeds (80mph). After I extracted the bolts and reattached the pulley she wont start. Cranks and backfires out of the turbo.

My first thoughts are that the timing jumped when the pulley bolts sheared. Is there anything else that i should check before pulling the valve cover to check the timing belt position?
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Old 12-14-2015, 04:18 PM   #2
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That sounds like an entirely reasonable assumption, and is the only explenation I can think of given the circumstances, which fits.
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Old 12-14-2015, 04:56 PM   #3
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If you aren't using a trigger wheel (OEM or other), and you didn't play with the coil connectors, then the TB probably jumped.
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Old 12-14-2015, 05:16 PM   #4
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If you aren't using a trigger wheel (OEM or other), and you didn't play with the coil connectors, then the TB probably jumped.

I have a trigger wheel. I didn't even know what to call it before now. This is something that has to be set up again?
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Old 12-14-2015, 05:47 PM   #5
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Make sure the sensor that detects the trigger wheel was not contacted and damaged or the air gap increased between it and the wheel teeth.
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Old 12-14-2015, 06:09 PM   #6
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Make sure the trigger wheel isnt on backwards.
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Old 12-14-2015, 06:46 PM   #7
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Thanks for the suggestions. I'll check and report back.
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Old 12-14-2015, 06:59 PM   #8
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Make sure the trigger wheel isnt on backwards.
+1
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Old 12-14-2015, 07:29 PM   #9
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Make sure the sensor is positioned correctly and not damaged from the pulley hitting it on the way out, the triger wheel should have a tooth under the sensor when you have the timing mark near the 10deg mark.
You may want to install biger bolts on the pulley if you keep the stosck balancer and track the car, i use them on my engines and it is cheap insurance since the bolts are known to break with sustained high rpm even in stock power levels
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Old 12-14-2015, 07:58 PM   #10
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All this talk of trigger wheels, in a car which has a "1.8L transplant."

Zoomy, what ECU is your car using? If it's the stock 1.6L ECU, or the ECU from a '94-'97 1.8 car, or an aftermarket ECU connected to a little distributor-like device plugged into the back of the head on the exhaust side, it'll run just fine without the trigger wheel.
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Old 12-14-2015, 08:12 PM   #11
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Quote:
Originally Posted by zoomy View Post
I have a trigger wheel. I didn't even know what to call it before now. This is something that has to be set up again?
Quote:
Originally Posted by Joe Perez View Post
All this talk of trigger wheels, in a car which has a "1.8L transplant."

Zoomy, what ECU is your car using? If it's the stock 1.6L ECU, or the ECU from a '94-'97 1.8 car, or an aftermarket ECU connected to a little distributor-like device plugged into the back of the head on the exhaust side, it'll run just fine without the trigger wheel.
Because
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Old 12-16-2015, 04:29 AM   #12
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To cover all bases, when you put the pulley back on, you did verify #1 was at TDC? If the markings on the pulley indicate correct timing, but it's 90 or 180 degrees out of phase, car no work.
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Old 12-16-2015, 07:41 AM   #13
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Quote:
Originally Posted by Mobius View Post
To cover all bases, when you put the pulley back on, you did verify #1 was at TDC? If the markings on the pulley indicate correct timing, but it's 90 or 180 degrees out of phase, car no work.
That is hard to do because there is a locating pin for the pulley and triger wheel the only thing that can go in wrong is the trigger wheel and that will cause the engine to back fire and not run
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Old 12-17-2015, 01:16 PM   #14
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Quote:
Originally Posted by Joe Perez View Post
All this talk of trigger wheels, in a car which has a "1.8L transplant."

Zoomy, what ECU is your car using? If it's the stock 1.6L ECU, or the ECU from a '94-'97 1.8 car, or an aftermarket ECU connected to a little distributor-like device plugged into the back of the head on the exhaust side, it'll run just fine without the trigger wheel.

I have an Electromotive TEC2 ECU.
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Old 12-17-2015, 01:30 PM   #15
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Quote:
Originally Posted by Mobius View Post
To cover all bases, when you put the pulley back on, you did verify #1 was at TDC? If the markings on the pulley indicate correct timing, but it's 90 or 180 degrees out of phase, car no work.
Quote:
Originally Posted by HHammerly View Post
That is hard to do because there is a locating pin for the pulley and triger wheel the only thing that can go in wrong is the trigger wheel and that will cause the engine to back fire and not run
Quote:
Originally Posted by HHammerly View Post
Make sure the sensor is positioned correctly and not damaged from the pulley hitting it on the way out, the triger wheel should have a tooth under the sensor when you have the timing mark near the 10deg mark...

I did not verify that the trigger wheel position when i put it back on. Please forgive my ignorance here, I want to make sure that understand this correctly.

The timing mark (flat spot on the trigger wheel) should be at the 10 deg mark as identified in the picture when the timing is TDC?

EDIT: For reference this is my trigger wheel kit. https://electromotive.com/our-produc...a-trigger-kit/

Last edited by zoomy; 12-17-2015 at 01:37 PM. Reason: added trigger wheel kit url
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Old 12-17-2015, 02:32 PM   #16
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The "tooth under 10 degree mark at TDC" rule is for the stock 1.8 trigger wheel, which has four teeth. Your 60-2 wheel may be completely different -- check the instructions that came with it.

--Ian
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Old 12-18-2015, 10:22 AM   #17
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I adjusted the trigger wheel last night and she started right up!

Thank you everyone for your help. You guys ******* rock.
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