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Shifted from 3rd to 2nd, think rod is knocking.......

Old 08-14-2003, 07:05 PM
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Default Shifted from 3rd to 2nd, think rod is knocking.......

Well, like the title says I took the car out last night to show an old friend how it runs, and did I ever. Every thing was great until I shifted from 3rd and instead of 4th I got 2nd. This happened with my old car and wiped out a crush sleeve in the rear end but not this time. Instead I have a ticking (sounds like an exhaust leak unfortunately its not) coming from the bottom/back of the off the oil pan. I performed a compression test and all cylinders were good. I have no doubt that I bent pushrods (since the engine probably saw the other side of 8000 rpm) but I am curious if the sound might be transferring from a spring or rocker arm and just sound like it is coming from the bottom end, but I will not be able to tear it down to find out until next Friday, so any input will be greatly appreciated. I really think that I spun a rod bearing but like I said I have to wait a week until I can tear it down at home.

Also people with a knowledge of a similar situation: Can pushrods give a ticking sound after a SEVERE over rev?

Also who makes/sells stroker cranks at a "good price"? If I am going to go into the engine I am going to make it worth it.

Thanks,
Bart
Old 08-14-2003, 08:11 PM
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Default Re: Shifted from 3rd to 2nd, think rod is knocking.......

I have experienced this myself but I was lucky. I only had three pushrods and two valves bent. But my noise came from the upper part of the engine but it was more from the back. I did a comp check at first and it all showed good pressure but it was low on two cylinders. I then did a leak down test and found that it was the valves along with the pushrods. It wasn't hard to change out the pushrods, and had to have head work done for the valves.
Old 08-14-2003, 09:00 PM
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Default Re: Shifted from 3rd to 2nd, think rod is knocking.......

You sound like you would know the difference between a top end and bottom end knock. If it's coming from the bottom, and you know for sure it's not exhaust, it's not going to be good. Seems like you'd have an oil pressure problem though. Won't hurt to throw some pushrods in anyway. See what happens then. Good luck dude.
Old 08-14-2003, 09:29 PM
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Default Re: Shifted from 3rd to 2nd, think rod is knocking.......

Definately not good, but since the compression check showed all good, do a leak down and take it from there. You may be just looking at pushrods/valves. What kind of noise(ticking or knocking)? Been my experience that a rod knock is of a lower frequency/pitch than a valve/lifter. Also...does the noise get louder or quieter as the motor warms from a cold start? Generally valve train related noise will quiet somewhat whereas rods/bearings will get louder during warm up.

Good luck
Old 08-14-2003, 10:14 PM
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Default Re: Shifted from 3rd to 2nd, think rod is knocking.......

I have the exact same ticking in my car, caused by the exact same thing. It's not pushrods in my car though, as we've pulled all of them, and they were all straight. I'm about 99.9% sure it's a few bent valves, as I still have great oil pressure, and no fluctuations. Also, when I changed my oil, there were no shiny, metallic particles in it.

While we're on the subject of bent valves, just how bad is it to drive around with them bent? I haven't experienced any power loss really to speak of, and other than the annoying ticking, there's really nothing wrong, other than the flashing SES light, which I'm assuming is a misfire code. I've also noticed a drop in gad mileage, but that was to be expected.

So, are there really any adverse effects to driving around with bent valves?
Old 08-14-2003, 10:15 PM
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Default Re: Shifted from 3rd to 2nd, think rod is knocking.......

Well, I checked the car out last night and "determined" that it was coming from the lower end. Today, I immediately pulled the plugs out and performed the compression test without restarting to again listen to the noise the car. I should have. I guess I thought that it sounded different than it actually did (if that makes any sense). I had jacked the car up last night and listened when I was very uptight and had prepared myself for the worst (and apparently convinced myself of the worst). The noise was a "transferring" and after further investigation with a stethoscope seems to be coming from cylinder #5 and does appear to be in the valvetrain. It is a ticking not a knocking. I will go ahead and replace all the pushrods bent or not and check all the springs. I am hoping that the valves are not bent and since the car is not running really erratically I think I may be in luck. All my O2's and fuel trims looked good and in my thinking if valves were bent then it would be affecting the fuel trims by making some cylinders run lean (depending on if it was an exhaust or intake valve) and would cause the O2's also show rich or lean condition (unless the ECM would be able to compensate for this condition). Well, I am taking off Tuesday so I will know for sure and there will be no more mistakes on my part. After I pull the valve covers and replace what ever it needs then I will then take it to a local shop and perform a leak down test (I don't have the equipment to do it at home).

As far as springs and pushrods: When replacing broken/bent valve springs and pushrods is it common to use the stock type pushrods and upgrade the springs? As long as the valves are not floating then I don't see a need for a pushrod upgrade and upgraded springs would cure this problem. Am I correct in my thinking?

Thank you for you help and your input.
Later,
Bart
Old 08-14-2003, 10:36 PM
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Default Re: Shifted from 3rd to 2nd, think rod is knocking.......

I have the exact same ticking in my car, caused by the exact same thing. It's not pushrods in my car though, as we've pulled all of them, and they were all straight. I'm about 99.9% sure it's a few bent valves, as I still have great oil pressure, and no fluctuations. Also, when I changed my oil, there were no shiny, metallic particles in it.

While we're on the subject of bent valves, just how bad is it to drive around with them bent? I haven't experienced any power loss really to speak of, and other than the annoying ticking, there's really nothing wrong, other than the flashing SES light, which I'm assuming is a misfire code. I've also noticed a drop in gad mileage, but that was to be expected.

So, are there really any adverse effects to driving around with bent valves?
How did you check for bent pushrods?

Do you have access to the tools to perform a cylinder leakdown test?

Was there any slack between the rocker arms and the top of the valvestems?

Do you have access to a scanner to see what code you are actually throwing? I think you are on the right track with a misfire code but Also I would be curious to see how long it takes for the code to reappear.

As far as adverse effects I could see how it could possibly pound out the valve seat and will cause excessive wear in the valve guide and could bend any new pushrods because they don't have full travel. Not to mention could allow the valves to be more prone to float and allow more dramatic damage in the event of the next occurrence.

Later,
Bart
Old 08-14-2003, 10:49 PM
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Default Re: Shifted from 3rd to 2nd, think rod is knocking.......

Well, I am going to sound like a breath of fresh air for you. I thing you just bent a couple of pushrods.

Pull all of them. Roll them on a flat pane of glass. Replace the bent ones.

I will bet that everything will be ok after that.

Don't worry about compression checks or cyl leak- down checks until you are sure all the pushrods are straight.

You will bend the **** out of the soft stock GM pushrods before you start bending valves ....

Good Luck,
Ron

P.S You don't pound out any of your rod or main bearings with that very short look at 7,000+ rpm. Had anything failed at that rpm for that short period of time, you would be looking at a big hole in the side of your engine, and your questions here would be of a very different nature ...

Old 08-14-2003, 11:06 PM
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Default Re: Shifted from 3rd to 2nd, think rod is knocking.......


How did you check for bent pushrods?

Do you have access to the tools to perform a cylinder leakdown test?

Was there any slack between the rocker arms and the top of the valvestems?

Do you have access to a scanner to see what code you are actually throwing? I think you are on the right track with a misfire code but Also I would be curious to see how long it takes for the code to reappear.

As far as adverse effects I could see how it could possibly pound out the valve seat and will cause excessive wear in the valve guide and could bend any new pushrods because they don't have full travel. Not to mention could allow the valves to be more prone to float and allow more dramatic damage in the event of the next occurrence.

Later,
Bart
We checked the bent pushrods by pulling them all, and rolling them on a pane of glass, just like you're supposed to.

There was no irregular slack between the rocker arms and the top of the valve stem, all was normal there.

I need to do a leakdown and compression test, along with scanning my car, and I'm sure that will pretty much tell me what is wrong for sure.

The funny thing about the SES light is, it will come and go randomly. I mean, I know that after every 3 starts it will turn the SES off, but it usually takes a while for the car to start acting up again. And the only time I will throw an SES is when the car is hot, and is idling, and then it will start idling kinda rough.


Tin Indian, I'm gonna have to disagree with ya there buddy. My car is a perfect example that if you still have the stock springs on the car, and you over-rev it, you can run into valve float and bend a valve. My car has 82K miles on it, VERY HARD miles I might add. I'm positive that's exactly what happened to mine. I went 3-2 instead of 3-4, and I guarantee you I saw 8K rpm's, which in turn floated some vlaves, which in turn smacked the pistons.
Old 08-19-2003, 03:04 PM
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Default Re: Shifted from 3rd to 2nd, think rod is knocking.......

*Update*
Pulled the pushrods today and had 7 bent pushrods. New stock type pushrods will arrive Thursday but I will have to wait till Sat to install them. I decided to use the stock type pushrods because I would rather the pushrod be the weak link than the valve. I still have a problem with my tranny (2nd gear is screwed) and have been afraid that I might have a problem again so I decided to keep the stock style pushrods until the tranny is fixed.
After the new pushrods are in I will perform a leak down test to see how bad I really screwed up.
Later and thanks for the help,
Bart
Old 12-30-2016, 12:57 PM
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Unhappy 3rd to 2nd - over reved

I had done the same exact thing. I went from 3rd to 2nd at the end of 3rd gear. it stayed in second for a few seconds and the engine shut off. I tried starting it and it fired right up and drove normally. Got to my destination and herd a tapping noise. Pulled into a parking garage and the tapping it only coming out of the exhaust exits. The engine bay has a slight hissing noise but not a single tap or knock noise. Engine bay I quiet other than the tapping from the exhaust exits.

I replaced the ignition wires - plugs & swapped coils from one cylinder to another due to the fact that I'm getting a P0300 code. Put the scanner on it and its showing cylinder 7 and 8 continuously misfiring.

What do you guys think?
Old 12-30-2016, 06:10 PM
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I did the same thing when I first bought the car, I have since installed a tick master and a MGW shifter and have never missed another shift.
I chased the tick down for months and knew it was in the #6 cylinder by using a mechanics stethoscope. I replaced pushrods, valve springs, trunion upgrade, oil pump and timing chain. It just wouldn't go away. I finally decided to to a cam and port the stock heads. All the lifters looked good along with the cam lobes, but when I went to lap the valves, #6 intake would not turn. I rolled it on a glass table and it was bent. I bought new valves and reinstalled everything. I took my time and made sure the pushrod measurement was spot on. It now has zero valve train noise.
Old 12-30-2016, 07:36 PM
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Seems like lots of people have trouble driving a manual car.

Oh, and reviving 13 year old threads...
Old 12-31-2016, 12:08 AM
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Originally Posted by JoeNova
Seems like lots of people have trouble driving a manual car.

Oh, and reviving 13 year old threads...
lol, didn't even see that!


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