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big problems......maybe?

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BJS1977

Guest
i hope someone can help or at least make me feel better. it was about 50 degrees he in PA on sunday so i thought why not take a ride. fired it up and i got a strange noise and it wouldn't start. looked under the hood and saw smoke coming from the carb!!!!!! i didn't really mess with it after that but i'm s***ing my pants. someone please tell me its not as bad as i think. the motor only has about 5000 miles on it and was real expensive. someone help. i'm gonna try to look at it today but i gets dark at noon here in the winter which makes it hard.
 
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Bullitt

Guest
Could you be more specific BJS1977? Exactly when did the car make the noise? Are you talking about a whine, a pop or what? Where did the sound seem to orginate from? Did the car die or stall? We don't want to give you bad advice, but we need some more details. --Bullitt
 
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BJS1977

Guest
usually when its cold like this it takes a few tries to start up. i pumped the gas turned the key and it made kind of a grinding noise. the car did not stall cause i stopped right there and didn't try it again. the grind sounded like it came from the bottom of the engine. i hate to say it but it kind of sounded like a metal on metal grind kind of like there was no oil or pressure. it has a new oil pump and the car is full of oil. it neve backfired before and always starts right up. what would cause a backfire?
 
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Bullitt

Guest
Many things can cause a backfire. It could be one of these things:
  • Faulty emissions system
  • Ignition timing incorrect
  • Bad distributor cap, rotor or wires
  • Carburetor needs adjustment
  • Improper valve clearances
Are you sure it wasn't the starter/solenoid? I know that comes out of left field, but it doesn't hurt to ask. When the oil pump was installed, do you know if the pick-up was welded or pressed on? If it was pressed, it might have come loose and fallen into the pan causing oil starvation. To find out if this happened, you're probably going to have to drop the oil pan. --Bullitt
 
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BJS1977

Guest
it has no emissions at all so it can't be that. the timing might be bad but i can't imagen it would go that bad so quickly but i'll check that. i drove it last week with no problems whatsoever. not even a hiccup. distributor cap, wires and rotor all brand new, but that dosen't mean much cause you never know. i'll try to check the carb today but i adjusted it early last week cause it was running a little fat. i don't know about the valves, how would i go about checking them? the starter is also brand new but again, you never know. i am pretty sure the oil pickup was welded but i didn't even think about that till now. this is gonnsa be real tough because i have no garage and its gettin damn cold real fast. lets go worst case senario here. what is the absolute worst thing it could be? don't spare my feeling give it to me straight. i'm crossing my fingers as we speck.
 
B

Bullitt

Guest
Let's start with the starter. What could have happened is that the solenoid decided to commit suicide. If this happened and it burned out, it shouldn't turn at all. The pinion or flywheel teeth might be broken causing very noisy engagement, which convinced you to stop. This can be checked pretty easily by looking for broken pieces in the transmission cover. Depending what you have, this is called a clutch cover (manual tranny) or a torque convertor cover (auto). Valve adjustment procedures are different for hydraulic and solid lifter camshafts. So which do you have? This should be done under a roof because you are going to take off the valve covers and don't want any excessive dirt. With the money you spent on the engine, you don't want to louse anything up, so check with the shop that did the work. If they didn't set the clearances right, you probably have some sort of restitution. I can't imagine this problem showing up after 5,000 miles and not sooner, though. Had you noticed any excessive oil consumption? Also, what carb are you running? I don't want to speculate on the worse thing, but here goes. If the engine was starved for oil long enough (start up is hell on the motor), the piston(s) might have seized in the bores and/or the piston rings galled them. I think this would have only happened though, if you laid on the starter excessively. There are some shops that have small probes that can look down into the bores via the spark plug hole and see if anything is amiss, if you are unsure about they're condition. I hope that it's nothing serious. --Bullitt
 
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BJS1977

Guest
i'll check the torque converter cover for extra pieces. i have a hydraulic cam. i have not noticed any excessive oil consuption but now that i think about it last time i changed the oil there was a small amount of metal stuck to the magnetic drain plug. it wasn't a lot so i disregarded it. could that be something? the carb is a 4 barrel holley 750cfm no vacuum secondaries or anything. the motor is actually a crate motor from american speed in ohio. if it's something big they will be getting a call. i have to check to see if they have a warrenty of somekind. its never been raced or anything so i'm hoping its something small.
 
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Bullitt

Guest
Being a thousand miles away or so, it's really hard to come to a conclusion as to what your problem might be. That's the reason for the number of variables I'm discussing. The reason I asked about the carb make is because a bad backfire will take out the power valve on a Holley. Was there a loud pop during your start up? If so, do you know if your Holley has a power valve protection? The older ones usually don't, but Holley started putting them on awhile back. When you noticed the metal in the oil, was it metal fillings, shavings or a chunk? Stick with the easy stuff for right now. Components that are easily checked with out much tear down. I had a car whose starter solenoid decided to get stuck and burn itself out in a strip mall parking lot. It made a terrible grinding sound and I couldn't get the key out of position, till it died. I had to perform the part swap in the lot on a Sunday afternoon. :( At least I got it fixed, but I lost a good shirt due to the amazing amount of grease and grime under that Caddy. I think I had to shampoo my hair six times before it stopped running the water black and was finally clean. :L --Bullitt
 

Rowdy1

Well-known member
Joined
Mar 26, 2001
Messages
1,180
Location
Lake Hopatcong, NJ
Corvette
1962 CORVETTE-SOLD 2004 Z16 Z06 CE
My Two Cents

Sorry to hear about your problem. If it were me, having a new motor, no matter who built it, giving me metal parts in the oil, I'd be dropping that oil pan. Something isn't right down there. As Bullitt said, it's hard to pinpoint without having it in front of you to see or hear anything. What kind of oil pressure did it have when you first fired it up new? How many times have you changed the oil & filter in that 5000 miles? After an oil change when you first start it to check for leaks and the fill mark, have you ever heard a knocking sound? If the engine ran fine last time you drove it, it's not likely the engine gremlins snuck in there while you were sleeping, something either was wrong from the builder or something is going wrong slowly and undoubtedly will give you a big problem if not fixed before you go any further. Who installed this crate motor, can you get it on a rolloff to a friends garage to do the trouble shooting? My "guess" is the puff of smoke was due to it being cold and it didn't start resulting in a backfire. Was the starter the original, or a new one and did you see if it needed to be shimmed?

First thing I'd do is drain the oil into a CLEAN container. Check the drain plug again, the oil, AND filter for ANY more metal. Let us know as you go, good luck.
 

69MyWay

Well-known member
Joined
Jul 3, 2001
Messages
4,364
Location
Auburndale, Florida
Corvette
1969 Killer Shark
I think we are all waiting for more details to help you pinpoint the problem.

Before jumping to conclusions, what is the chance that the alternator bearing failed (grinding noise) and or the power steering or even the a/c pulley bearing.

In 50 degree weather, I would expect to see some smoke come out the carb hole if the motor had not fully warmed up yet.

Sometimes we want to dive in with both feet, when the problem is right there on the edge.

You might try slipping the belts of the engine and firing it back up to see if all it quiet on the engine front.
 
Joined
Nov 4, 2000
Messages
947
Location
Scottsville, Kentucky
Corvette
08 Jetstream Blue Z51 coupe
Exactly! 69MyWay makes several good points. I would like to pass on this tidbit as well, and I don't me to offend anyone's opinion in doing so. All new or re-built engines, gas or diesel will show varying amounts of metal large and small at the first and even 2nd oil change. If there still tossing metal after that, worry. Most engine builders, including GM, Cat and others recommend the first oil change on new or re-built engines to be at 1000 miles or 100 hours of operation. I have cut open oil filters as part of a preventive/predictive maintenance program on new and re-built engines for many years, including my own personal vehicles. I can promise you that enormous amounts of mostly bearing & bushing material rub off in the first few miles or hours on every engine and get stopped by the filter before they cause damage. Watch your filter, they are fairly easy to cut open. Remove the paper and squeeze out the oil. Then spread open the accordian and look for metal shavings/flakes. They should be limited to a piece or two (or none)after the second oil & filter change.
 
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BJS1977

Guest
i tried to take a look yesterday after work but it was too dark. i'm gonna take a half day on wednesday and get dirty. i installed the motor myself but had my mechanic check it out before i fired up just in case. everything was fine so i fired it up and no probs. changed the oil about 500 miles later. it ran great and i haven't had any probs. i don't know if the metal has always been there but i just noticed it recently. it is very minimal however. a couple of small shaving. the oil pressure has always been about 25 to 30 psi when warm. i've changed the oil 4 or 5 times since i installed the motor. no knocking sound or anything. the starter is 2 years old but a stock replacement i don't know if that makes a difference with a motor that make much more power than the original. i also have headers. i was thinking maybe the heat from the headers stressed out the starter? i have no ac and the alternator is a year old but i will look into that. i'd like to thank everyone for their help. lets hope its something small cause if i have to rebuild that motor i can not be held responsible for my actions.
 
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BJS1977

Guest
the good news it that i can get it started but the bad news is that it won't run long. it sounds good but runs real choppy and won't stay running for more than a few seconds. i'm a little afraid to pump the gas hard cause of the back fire problem. so now i'm guessing carb probs. i'm not sure how to check the carb though if i can't keep it running long enough to get a good look at it. any suggestions?
 
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Bullitt

Guest
Do you still have the grinding problems of metal to metal contact? Find anything in the oil or inspection cover? The rough running could be attributed to it, but let me stay with the carb for now. You might as well take down the carburetor, if you're afraid to harm it any further. If it did backfire and took out the power valve, you're going to take it off anyways for the rebuild. Besides, at least you can take it inside to work on and not have to be in the cold. It sounds like you're going to have to use the process of elimination. Hopefully, you'll find the problem before you spend too much time and money hunting it down. --Bullitt
 
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BJS1977

Guest
well...more good news and bad news. the good news is that there is no metal in the oil and the grinding sound seems to be gone. thats the good news, the bad news is that its not the power valve. after i replaced it and got the fuel lines hooked back up i tried to start it and it backfired again!!!!! this leads me to believe that its not the carb. the spark plugs and wires all look good so now i'm kinda stumped. it still running real fat so its getting too much gas but the power valve was new the floats were set and the idle was ok. what else in the carb would make it run fat?
 

69MyWay

Well-known member
Joined
Jul 3, 2001
Messages
4,364
Location
Auburndale, Florida
Corvette
1969 Killer Shark
Check and see how tight the distributor is clamped down. It may have spun a tad (grinding noise) and your timing may be a mile off making it back fire and run rich.
 
R

rpounds

Guest
I would start with a compression check. You may have jumped a couple of cogs on the timing chain. If so, the compression will show up low.

If the timing is off, but the distributor is tight and has definitely not moved . . . timing chain.
 
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BJS1977

Guest
this weekend i'm checking the timing, the power valve (again) and anything else i can think of. this is frustrating. its been nice all week and its killing me. there ain't too many nice days left and i'd like to catch a few.
 
R

redmist

Guest
Very interesting thread, hopefully it will have a happy ending. Based on the info presented I would eliminate the carb as a problem. It sounds very much like a timing issue.
I know it runs pretty crappy now but if you can get a buddy to keep it running while you turn the distributor you may be able to gather some more facts.
Once you get it running the best this way take a look at what the timing actual is. If it is outside the range of "normal" it could be a timing chain issue.
An off the wall thing to check is an exhaust restriction.
 
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Bullitt

Guest
I think that what everyone is saying about the timing makes sense. I wanted to ask about the chain "jumping," for some general FYI. If the chain did jump, what would cause this? Improper torque specs, no thread locker, no cam button or what? If the cam was installed straight up, could the jump throw the timing off enough to bend a valve, or would it just retard or advance the timing? I know with each different case it's hard to be specific, but if anyone has dealt with this, I'd like to know more about their experience. --Bullitt
 

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