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Definately Retime After Distributor Removal! by zkhennings
Started on: 11-10-2013 06:03 PM
Replies: 9 (337 views)
Last post by: zkhennings on 11-15-2013 08:34 AM
zkhennings
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Report this Post11-10-2013 06:03 PM Click Here to See the Profile for zkhenningsSend a Private Message to zkhenningsEdit/Delete MessageReply w/QuoteDirect Link to This Post
So when I built my new engine in the summer of 2012 I set the timing to 10* with a timing light and all was good. I made a mark at this advance on the distributor/block.

At the end of summer 2013 I needed to replace the LIM gaskets which stopped sealing amazingly as the heads settled. I made a mark on the distributor under the cap to remember the rotor position.

I reinstalled the distributor and it appeared as though both the distributor was in the original location as well as the rotor from the marks I had made. The car ran and drove decently but it felt a little low on power at the upper RPMs but I did not think it was the timing. I knew I should re-time it but I figured it was really close like within a few degrees.

I finally got around to re-timing it today, went to HF and got the $30 timing light, which has its issues like brightness (had to time at night), but from the reviews is accurate which is all I really care about since I am not timing cars all the time.

Anyways, when I checked the current timing (after jumpering AB) it was hanging out around 30 degrees advance! I dialed it back to 10 and the car feels much better and the idle is much more stable. It never seemed as though my engine was running any hotter than usual and I heard no pinging so I was shocked it was that high. I must have installed the distributor a tooth off, and my marks were big enough to make it appear as if they were lined up well enough. It is now 2-3mm off of the original mark which is not a lot.

But then I realized the distributor only spins 1 rotation per 2 crankshaft rotations. So that 2-3mm equated to around 10* of extra distributor rotation which resulted in 20* too much crankshaft rotation with respect to the original 10* of advance, resulting in my 30* base advance.

So don't wait like I did! Even if everything looks good and you are decently confident your timing is fine, check it!
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Patrick
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Report this Post11-11-2013 12:43 AM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by zkhennings:

Anyways, when I checked the current timing (after jumpering AB) it was hanging out around 30 degrees advance!


I find it extremely difficult to believe that your engine would run at all if it was timed 30° BTDC (with the jumper properly installed).

I suspect the outer ring of your harmonic balancer has spun.
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tesmith66
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Report this Post11-11-2013 08:01 AM Click Here to See the Profile for tesmith66Send a Private Message to tesmith66Edit/Delete MessageReply w/QuoteDirect Link to This Post
Been yanking distributors for over 25 years. I always mark the location of the distributor to the intake and the rotor do the distributor body. Have never had to re-time. I suspect bad balancer as well.

Putting a "stable" mark on an unstable surface (the all important timing mark on a rubber mounted surface known to slip from its original position) is just bad design.
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zkhennings
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Report this Post11-11-2013 11:36 AM Click Here to See the Profile for zkhenningsSend a Private Message to zkhenningsEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well the timing is definitely not retarded right now, and I brought it back 20*... I brought it back to 0 first and it still ran so maybe you would be surprised at the range it can run. When my timing is retarded by a few degrees it crackles and pops a lot on decel... And it isn't doing that. Also I've seen plenty of pictures of the 2.8 balancer and my timing mark is in the same place as theirs... How many degrees away from the keyway is the timing mark supposed to be so I can check to know for sure? I really don't think it has slipped, it is one of those things I keep an eye on.

And regardless, what can seem correct or close to correct can be really far off as I stated a few mm correlates to 20* regardless if my balancer has slipped or not.
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rogergarrison
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Report this Post11-11-2013 05:35 PM Click Here to See the Profile for rogergarrisonClick Here to Email rogergarrisonSend a Private Message to rogergarrisonEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by tesmith66:

Been yanking distributors for over 25 years. I always mark the location of the distributor to the intake and the rotor do the distributor body. Have never had to re-time. I suspect bad balancer as well.

Putting a "stable" mark on an unstable surface (the all important timing mark on a rubber mounted surface known to slip from its original position) is just bad design.


Me too. I use a chisel to mark the distributor base AND the intake. Simply match the marks together. I always make sure the rotor is pointing straight forward on every one so I cant forget.

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zkhennings
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Report this Post11-12-2013 06:32 PM Click Here to See the Profile for zkhenningsSend a Private Message to zkhenningsEdit/Delete MessageReply w/QuoteDirect Link to This Post
Ugh I don't know what is going on with my ignition system and maybe this is supposed to happen but I did not think it was.

I went to check the timing again and it was in the same place. But the same place does not mean that much since at idle it jumps around between 8 - 12.

When I jumper the car when it is running at idle the timing drops a lot down to ~10 degrees like it should. I see this as an indication that the jumpering is working to remove the ECM's affect on the timing.

I had my friend hold the car at around 2000 rpms to get a more stable reading, and as I understand it the timing should stay a constant 10* if jumpered as the ECM cannot affect the timing. When the car was at 2000 RPMs the timing was significantly higher like 5 - 10* higher than at idle.

Is there any reason this should happen? I am very sick of the fiero's stock electronics on the 2.8!
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2.5
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Report this Post11-13-2013 11:20 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
Make sure the engine is at operating temp when you check the timing.
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zkhennings
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Report this Post11-13-2013 12:14 PM Click Here to See the Profile for zkhenningsSend a Private Message to zkhenningsEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by 2.5:

Make sure the engine is at operating temp when you check the timing.


I have been letting it warm up first but IDK if that would affect that
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Spoon
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Report this Post11-14-2013 11:39 PM Click Here to See the Profile for SpoonSend a Private Message to SpoonEdit/Delete MessageReply w/QuoteDirect Link to This Post
Try checking your rotor for wiggle. That could throw your timing off. I just checked mine a few days ago and its all the way down on the key-way and I can twist it 1/8" either direction without the shaft moving. I have to check and see who made it. I know it's red in color.

Spoon


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"Kilgore Trout once wrote a short story which was a dialogue between two pieces of yeast. They were discussing the possible purposes of life as they ate sugar and suffocated in their own excrement. Because of their limited intelligence, they never came close to guessing that they were making champagne." - Kurt Vonnegut

[This message has been edited by Spoon (edited 11-14-2013).]

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zkhennings
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Report this Post11-15-2013 08:34 AM Click Here to See the Profile for zkhenningsSend a Private Message to zkhenningsEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Spoon:

Try checking your rotor for wiggle. That could throw your timing off. I just checked mine a few days ago and its all the way down on the key-way and I can twist it 1/8" either direction without the shaft moving. I have to check and see who made it. I know it's red in color.

Spoon



Thanks I will check that, it has not been replaced since I first replaced it... and it is just crappy Azone brand
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