Engine timing - timing scale missing

twinspar

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Hi all: I need to ask if anyone can post a photo of the timing scale for a 1988 Sunbird GT 2.0L Turbo. Mine's missing and I'm trying to figure out how to set initial timing. If someone has a photo, maybe I'll have a better idea of where the timing should be set - I might even be able to fabricate a crude scale that I can attach. I see one notch on the harmonic balancer, but have nothing to time it to. I know once the 4-wire ECM connector is connected, the ECM then controls ignition timing, but I want to be able to set initial timing before turning control over to the ECM. If anyone knows where I can get a replacement scale, that'd be great. Appreciate any hints anyone may have.
 

melsg5

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Does your engine have a distributor?
Why are you trying to adjust ignition timing?
 

twinspar

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Yes, I have a distributor. This is an engine installation after rebuild - I just want to start with timing near where it should be. I've had it running, and it seems to be running OK, but my scanner is telling me that (ECM controlled) timing is 24 degrees, and I'm getting a knock sensor (EST Electronic Spark Control) code 43.
 

melsg5

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Maybe someone else has an example.
Meanwhile, with engine at #1 TDC place a line on the timing cover where the balancer line is, that's zero. Measure the diameter of the balancer and divide by 360. That value is the distance from zero to 1 degree. Assuming you know what initial is supposed to be you can place that mark on the cover.
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92 Sunbird LE

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I'll look in my Sunbird books to see if it shows anything... give me a day because they are buried......I"ll take a pic of mine too, its still there. What big city do you live near ? ( might be able to track one down close to you )

Doug in P.R.
 
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twinspar

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Thanks to melsg5 and Doug. Now I've got bigger problems.... Occasionally, when cranking, I'd hear an unhealthy noise from the valve train - like a spring-loaded hard knock. Previously, once running, the noise was gone and the engine ran well. However, when I had it running the other day, I had a dead miss on cyl 1. I checked the spark plug and wire, both were OK. Since I had the plug out anyway, I pulled the rest and did a quick compression test, and got no compression on cyl 1. Next I pulled the cam cover and found the rocker on #1 intake broken cleanly in 2 pieces (see photos). Fortunately, the cam appears to have suffered no damage. I have no clue how or why the rocker broke - my research indicates this is a non-interference engine, so even if a piece of the rocker arm became wedged between the cam and valve stem, holding the valve open, it shouldn't have contacted the piston and/or bent the valve. This also doesn't explain no compression. I've ordered a bore scope and hope to have it in a few days so I can visually inspect cylinder #1 to understand why I'm getting no compression. Any chance there's a way to install a new rocker arm without pulling the head? I'll keep you posted with the results of the bore scope inspection.

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92 Sunbird LE

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Timing marker built on plastic cover



Doug in P.R.
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twinspar

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Hi Doug. I have tried numerous times in the last couple of months to register on the J-Body.org forum, but they apparently have server issues, and new users can not submit a registration. If you click their "Register" tab, you'll see what I mean. Do you know if Chris is a member on the pontiacforum?
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pippo

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My 87 sunbird GT non turbo also has no timing scale, mystified me for years. I concluded it was the way it left the factory. The computer takes over the timing, no matter how you set it (unless you set the dist cap so far out of wack). Eventually, the computer evens out/smoothes out the timing. Best I can describe it.
 

92 Sunbird LE

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Found his email ( I Think ) sent him a message there too....

Doug in P.R.
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