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mysterious timing gremlin

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Old 02-08-2001, 11:45 PM
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mysterious timing gremlin

Ok....I have an 87 suburban with an L05 that I drive at school up here in winona minnisota. I purchased the vehicle in mid december for 750 bucks- a real steal. I was driving last thursday night in the blistering cold, paked it and went to sleep. I woke up the next morning to go to work at the chevy dealer and my burb ran for sh*t. I did a tune up on it and set timing before i left so I figure its probably a weak pump or something like that. I Limp it over to dealer to have them do a pump because I dont have the facilities to do this kind of work and after a while the find out that my spark timing was retarded 30! degrees. What the hell could have caused this? Why r they trying to charge me 3 hours diagnosis? Is this outrageous to anyone else, or am I the only one who doesnt like to take it in the **** from the dealer.

Any insight would be greatly appreciated
-Nick

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91 RS W/carbed 350, Vortec heads, performer rpm, Comp cams Xtreme energy 224/230 duration and .477/.480 lift. BFG Drag radials. 3.42 posi,Corvette servoed 700r4, ****ty stock converter. Edelbrock TES, 3inch cat, flowmaster with single 2.5 inch exit.
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Old 02-09-2001, 12:17 AM
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Car: yep
Engine: uhuh
Transmission: sure does
I just recently had a SBC come in that was retarded about 40 degrees, I reset the timing and it ran fine for a while.

It started running sh*tty again and I checked the timing, 30 degrees retarded!! WTF??

What I found was that the roll pin holding the dist. gear had sheared off and was on so tight that the timing would slip, and stick for a while.

I would look very carefully at the gear. The pin looked good (it was still visable) but the gear tapped right off.


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Old 02-09-2001, 01:04 AM
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I will definately have to do that.
Thanx
Old 02-09-2001, 08:02 AM
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wow, i think that wins the 'esoteric problem of the year award' engineboy...
...ed
Old 02-09-2001, 10:29 AM
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you havent seen problem of the year until youve had a brake pad fly out of the caliper and get lodged in the wheel causing your front right wheel to lock up and pull you strait towards a curb. All this on an 86 ranger that hadnt had a brake job in a year!
Old 02-09-2001, 11:27 AM
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Aww, thats not that cool vortec. I mean, it was real easy to troubleshoot at least.Hell, the wiring gremlin that made me take my whole GP dash apart to figure out why ECM power got cut when you opened the doors only to find a missing fuse was the culprit was cooler than that. His problem was way cooler still, how easy would it be to overlook the pin had sheared when it still looked like it was in there and the gear wasn't falling off?
...ed
Old 02-09-2001, 06:25 PM
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Car: yep
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Transmission: sure does
Yep, that one had me stumped for a while.

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Old 02-10-2001, 10:07 PM
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Are you sure the clamp was tightened down?

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Old 02-10-2001, 10:24 PM
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<font face="Verdana, Arial" size="2">Are you sure the clamp was tightened down?</font>
Check the distributer hold down bolt before pulling it out.If it is tight,check for a bad timing chain/gear.The chain can stretch over time and can jump a cog.
I would definatly check all this first before pulling the distributer out.I think pulling it out would be a last resort.


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[This message has been edited by Kevin S (edited February 10, 2001).]
Old 02-10-2001, 11:08 PM
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we're not talking valve timing here. this is ignition timing and ignition timing only. once I brought timing back to 0 the truck ran fine. The hold down was tight
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