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Checking for timing jump

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Old 06-27-2011, 08:16 PM
  #46  
dr bob
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Originally Posted by Charley B
So I guess it's not an effective procedure to just push it back together again and secure it to the bracket.

Do you have the 944 part number?
I don't have the number handy, but it's the part that came in my intake-refresh 'care package' a couple summers ago. Rob Edwards pointed out the difference in cable length (manageable) vs the difference in cost of the 928 part. Check the regular suspects and you'll get the right part.
Old 06-27-2011, 08:22 PM
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Rob Edwards
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Hall sensor = 944 606 170 02.
Old 06-27-2011, 08:46 PM
  #48  
Charley B
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Thanks guys.
Old 06-27-2011, 09:09 PM
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Bill Ball
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Originally Posted by Charley B
So I guess it's not an effective procedure to just push it back together again and secure it to the bracket.

Do you have the 944 part number?
You could do that. Be careful to get it back together in the correct orientation. Once you pick out the remnants, if any, out of the female half of the connector you probably won't be able to tell which way it goes togther and that could be a problem. Then you would have to cut back the wire sheaths to check wire colors at the connector.
Old 06-27-2011, 09:37 PM
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Charley B
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Originally Posted by Bill Ball
. Then you would have to cut back the wire sheaths to check wire colors at the connector.
I thought it would be best to leave the remnants in place. It looks like a pretty clean break.

Should I leave the water pump in place until we have a chance to do the compression test?
Old 06-27-2011, 11:00 PM
  #51  
Charley B
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Originally Posted by Mrmerlin
............... also remove the left cam gear bolt after fitting 3 small bolts to the rotor holes so the pulley wont turn on the cam / spider,
You would be looking for a snapped left cam snout.
Once the belt is off, how do I imobilize the cam gear in order to break the bolt loose?
Old 06-27-2011, 11:35 PM
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Imo000
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Put a wrench on the hexagonal looking washer and use another wrench on the cam bolt. Then squeez the two together untill the bolt cracks loose. If this doesn't work, get some extensions on the wrenches.
Old 06-28-2011, 12:10 AM
  #53  
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hex washer under the cam bolt is a 30MM the cam bolt is 17mm,
once you remove the rotor put 3 small screws back into the rotor threads to hold the cam spider in alignment with the cam pulley, THEN loosen the cam bolt,
NOTE use the rotor bolts to figure out the correct length if the screws are too long they can damage the radial seal
Old 06-28-2011, 01:17 AM
  #54  
Charley B
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Not sure what I'm looking for here.
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Old 06-28-2011, 02:21 AM
  #55  
Bill Ball
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Charley:

Jim Morton gave me an idea for doing a leakdown before we replace the timing belt. If we find a bent valve, there's no point in doing the belt.

So, set the crank to 45 degrees before TDC. Then we will pull the timing belt (it appears you may have already done this) and rotate the cam (put the gear bolt and hex washer back on) to TDC for each cylinder and do a leakdown, leaving the crank as it is. We only need to do this for the driver side. If things check out then we will proceed with the timing belt job.

Can we do this Tuesday (tomorrow) afternoon (1 PM) instead of Wednesday?
Old 06-28-2011, 04:46 AM
  #56  
Charley B
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Sounds good Bill. See your around 1PM.
Old 06-28-2011, 11:32 AM
  #57  
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while you have the bolt out of the cam pull off the gear and inspect the rearside , look at the spider and see if its has any cracks.
The rusty dust mixed with what looks like metal chips in the picture could be a damaged cam ,
see also if the cam snout can be moved
Old 06-28-2011, 12:44 PM
  #58  
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Originally Posted by dr bob
Charley--

What's left of the connector looks fine. The missing part is still inside the part you have on the end of the harness. A small dentist's probe can be used to break up and extract the remnants stuck inside.

The Hall sensor lower bolt can be a real chore to get out. .
If you can get some penetrating oil on it also it may help. Its a B1TCH!!


6 deg. of timing across the board is what you have lost with it unhooked i believe.

On that picture of the cam gear/pulley...those arent the stock screws.
Old 06-28-2011, 01:41 PM
  #59  
Charley B
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Originally Posted by Tony
...............................On that picture of the cam gear/pulley...those arent the stock screws.
Those are temporary while the rotor is off.
Old 06-28-2011, 09:43 PM
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Well we made some encouraging progress today. Bill stopped by and we did a leak down test on the left side. 2 to 4 percent loss on each cylinder so it looks like I dodged the bullit this time.

We couldn't come up with a good explanation for the timing jump and damaged belt.

I took the opportunity to remove the right cam gear back cover in order to change the hall sensor without renewing my contortionist license.
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