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Do I really need to replace my engine?

3K views 17 replies 11 participants last post by  orange15 
#1 ·
The other day, I floored it in my goat to pass a few other cars. A minute or two later I started hearing what sounded like a sewing machine on metal coming from the engine at anything above 1500 rpm. The sound increased in volume and speed the higher my RPM went. I checked the oil and found I had maybe 2 quarts remaining (WTF!!) I could not locate any sign of an oil leak.

I took it to a local auto shop to have it checked out and the best they could tell me was that it is lower engine noise (maybe a piston hitting the block). They said the motor would need to be entirely replaced and quoted me a price that is more than the current value of the car. It seems like they are not a shop that is capable of doing engine rebuilds.

My questions for you great Goat owners are 1) Does anyone have recommendations on performance shops around South Carolina? I’m in Columbia but I’m willing to drive a little ways for a good shop that’s familiar with GM cars 2) Any ideas on what is causing the sound that I’m hearing? 3) How long do I have before the motor totally quits? 4) What is more cost effective: replace or rebuild the motor? And 5) If this was your GOAT, what would you do? Upgrade the motor? Scrap it? Part it out?

Thanks!
 
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#2 ·
it could be quite a number of things. i would bet on bottom end, considering how the oil is fed through the engine. rod bearings are the last thing to get oil, iirc.

as far as trying to ascertain where it's coming from, you could start killing the power to each cylinder in turn and see if it changes the noise. if it does, that would indicate something on the bottom end, as it would effect the force on the piston/rod/crank and thus the associated rod bearing. you could try timing the noise to compare the frequency to engine rpm as well, but that would be hard to do at anything over idle.
 
#3 ·
First place to start is to drain the oil then hit it with a flash light. If it looks like a starry sky you know the bottom end is done. Then cut open the filter if the oil doesn't appear bad. Pulling the plugs and valve covers would be my next step to make sure you dont have a broken spring, bent pushrod, broken off electrode etc.
 
#5 ·
Validate the diagnosis first. Many shops just want the money and won't look into it any further.

Draining and checking the oil/filter is a good idea. You can pull the valve covers easily and see if its in the upper valve train. Buddy of mine had a rocker go bad and we both swore up and down it needed a major engine rebuild based on how loud it sounded.
 
#6 ·
I'm with Steel Chicken, check the rockers/springs first. An oil change is another good suggestion. Based on your questions, though, sounds like you're in over your head. If checking the rockers, springs and oil are inconclusive, I'd see about selling it cheap on CL to try and get out before you get in trouble trying to rebuild it.

Also, don't throw a junkyard iron 6.0 in there. You'll add 100lbs to the nose and it'll drive like a different car. That's fine if you want to turbo the car, but it doesn't sound like something you'd be into.
 
#7 ·
pull valve covers first. you don't even have to drain the oil, just do it when the engine is cool and been sitting. I just had a rocker arm failure that sounds pretty much like what you are saying, rhythmic sewing machine sound. At least start there, easy to access and can rule out a top end failure quickly and easily.
 
#9 ·
I have an LQ9 in mine and haven't really noticed a difference in feel. Hope your engine is good tho, cuz pulling the engine is a pita. Cheapest option for you is dropping in a junkyard 5.3 or 6.0. I'd go with a 6.0, because you can get more power N/A with the same weight as the 5.3. And if you get the correct 6.0 iron block, it will drop right in 0 tuning involved. Just my .02.
 
#17 ·
...if you get the correct 6.0 iron block, it will drop right in 0 tuning involved. Just my .02.
No non-LS2 6.0L will be an exact tune-for-tune replacement. For example, the LQ4 and LQ9 have different camshafts, chamber volumes, and compression ratios than the LS2. The later engines also change to the 58X reluctor, and may have rectangular port heads. Will they run? Yeah, but the tunes aren't optimal.

Mechanically, the Gen 3 iron blocks also have different knock-sensor and cam sensor locations, which someone needs to be aware of if putting one in a '05/06 GTO.
 
#11 ·
Staying mainly in background. However, I would bet the farm you spin a rod bearing or more. I have seen a number off engines spinning bearing at oil levels you had, i.e. 2 quarts. Continued driving in time could break a rod and no rebuild would be available. If its not too bad, you can regrind the crank and replace the rods involved. The block and heads will need the be thoroughly cleaned to remove any material left from the damage. As for rebuild, Carolina Auto Masters in Burlington, NC, the owner is Jeff Creech, (919) 680-3966. He has vast experience with LS cars and engines. Give him a call and tell him Bob Reese gave you his recommendation. Whatever the case, rebuilding or replacing LS stuff is not cheap. Good luck.

Bob
 
#13 · (Edited)
Smurf that, unless you just want a seasoned iron block as a base. IMHO swapping a junkyard short or longblock in is ok for bewst junkies or cheap garage builds. They're good motors and stout, don't get me wrong.

I would want to spend the cash and really build it. Make it better than the original.

Too bad ERL isn't around anymore. The superdeck engines were amazing, and I really wanted to have them do a 427 for me.
 
#14 ·
If all you want is a replacement engine, plenty of low mile LS1 and LS2 motors out there, many of them out of other GTO's unfortunately. You will pay a bit, probably 3k to 4k for a decent engine.

I did this once with my 04 and parted out the original engine. Still running strong. Found a running LS1 still in the car and bought it. Actually went down in mileage, lol. Not counting additional supplies and tools i purchased, and the time and effort, i almost broke even. I forget how much i was short by. In my case all i had was a bent rod and a piston with a ding in the skirt. Depending on how much damage you have (if you have much at all) you may be able to do the same thing.

Or, find a reputable builder that offers a warranty and use your engine as a core. Pulling the engine in case of a warranty claim will suck if something happens in the future, but at least you have a little garuntee there.
 
#16 ·
If it is a bottom end rotating assembly thing and this isn’t your only vehicle, I would pull the motor and rebuild the rotating assembly with a 402 as you have the time/funds available. But that’s just me and I like having a fun project if I have to dump money into something.
 
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