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Engine noise - towed home - what could it be?
- Thread starter RedTR3
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TR3driver
Great Pumpkin - R.I.P
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If the valve had broken, it probably would have taken the piston out with it. When Dad's TR3A swallowed a valve, it took out the liner, and connecting rod, and cylinder head as well.RedTR3 said:
You might get away with just changing the piston & rings for that cylinder, which is fairly easy on a TR.
CJD
Yoda
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Gee...
I can't place those pieces as any particular engine part. If the engine was running well, my bet would be the carb swallowed something.
The head has to come off. But cross your fingers...it may have done minimal damage if the FO was small. Be sure to fill us in when you get it apart...the suspense is killing me!!
John
I can't place those pieces as any particular engine part. If the engine was running well, my bet would be the carb swallowed something.
The head has to come off. But cross your fingers...it may have done minimal damage if the FO was small. Be sure to fill us in when you get it apart...the suspense is killing me!!
John
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RedTR3
Jedi Trainee
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OK, but I am not sure how the carb can "swallow something", you mean that perhaps some debris was in the manifold and worked its way into the cylinder?
Anyway, I'm going to get towed to the shop on Wednesday and we'll find out - I will post the diagnosis later in the week.
I am hopeful simne the engine was running well.
Anyway, I'm going to get towed to the shop on Wednesday and we'll find out - I will post the diagnosis later in the week.
I am hopeful simne the engine was running well.
CJD
Yoda
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I don't know...totally stumped. I only bet on something getting sucked in as it doesn't look like anything I can think of in the engine. Not enough curve for rings or valve...not round enough for a carb bolt or screw...but then those can't be totally ruled out if they got well chewed up.
I had a friend years ago with a Boss 302 Mustang. It started rattling...so he revved it to about 6 grand to try to clear it. Bad idea! When we took it apart, someone had dropped a handful of nuts and washers down his intake. Either he [censored] someone off or they were just jealous of his cool car. After that I don't rule anything out on a car with a non locking hood.
I've had cars swallow valves, chew seat inserts, drop guides, hole pistons, and eat the screws holding the carb together. It all came out looking recognizable, though
Like I said...the suspense is killer here!
Oh, just a thought...has any work been done on the car recently? Sometimes a little history of work can give a clue. Some FO can get caught by the intake valve for a while before it lines up just right to make it through into the combustion chamber.
John
I had a friend years ago with a Boss 302 Mustang. It started rattling...so he revved it to about 6 grand to try to clear it. Bad idea! When we took it apart, someone had dropped a handful of nuts and washers down his intake. Either he [censored] someone off or they were just jealous of his cool car. After that I don't rule anything out on a car with a non locking hood.
I've had cars swallow valves, chew seat inserts, drop guides, hole pistons, and eat the screws holding the carb together. It all came out looking recognizable, though
Like I said...the suspense is killer here!
Oh, just a thought...has any work been done on the car recently? Sometimes a little history of work can give a clue. Some FO can get caught by the intake valve for a while before it lines up just right to make it through into the combustion chamber.
John
CJD
Yoda
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I'm crossing my fingers for you. If the FO was small, there's a chance you can get by with just a nicked piston. A little work with an abrasive wheel might clean it up. If it's large, then it usually cocks the piston and cracks things, like the liner and head. The good news...when you do crack something, you normally see a lot of white smoke (steam) out the exhaust. If you didn't get that, there's still hope!
John
John
This is a tough one for me to watch. I am thinking a shop in order to guarantee their work would have to pull the oil regulator off pull the head and the pan and perhaps the chain and even perhaps the crank. that being said and this is one of my dumber thoughts so do not laugh too hard. I think John’s theory has merit it looks like something else other than engine parts, if so and the damage is perhaps mostly done and if you can see the top of the piston with a good light and me being a cheap hillbilly could I clean the cylinder out with air and oil through the plug hole?
steve
steve
TR3driver
Great Pumpkin - R.I.P
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You can't really see enough of the piston through the plug hole, unless you happen to have a borescope handy. Also, the loud rat-tat-tat would be the FOD being driven into the piston.
So IMO it would be foolish not to pull the head. Having tried both, I'd rather take a chance on reusing the head gasket than breaking a piston.
So IMO it would be foolish not to pull the head. Having tried both, I'd rather take a chance on reusing the head gasket than breaking a piston.
I hear you Randall and clearly that is a sound avenue to travel. I was just thinking of a 71 spitfire I had in 74. One of the pistons had broken in half and I was not sure of what was going on. I drove it for a couple of more weeks before I tore the motor out. I was just thinking he is looking at 2K+ if they tear into it, so what the heck clean it out good and fire it up. See what it sounds like. It is most likely new motor time anyway.
Steve
Steve
TR3driver
Great Pumpkin - R.I.P
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My point is that pulling the head on a TR3 motor is a relatively simple and inexpensive operation; and doing it now may avoid further damage. Since it is a wet liner engine, even a broken piston is not particularly fatal (or even expensive if you find used parts).
The piston I showed above came out of my own TR3A. Being somewhat impecunious at the time, I found a used set of pistons & liners plus the cylinder head from another engine (broken piston was due to severely worn valve guides). My total outlay was under $300 ($400 if you count the spare head) and a few days of my time. Could have been less than that, but I also popped for new rings, rod & main bearings. That must've been around 1995, so the prices have gone up somewhat. But that also means I drove that motor another 100,000 miles or so and it was still running well when the car got wrecked (2005).
I have even gotten away with reusing the head gasket (when reassembling with the same block & head). Intake & exhaust gaskets can be cut from "high temp" gasket material (or they used to be available apart from the kit for under $10/pair). And while I don't recommend it, in a pinch you can use silicone RTV for a pan gasket.
The piston I showed above came out of my own TR3A. Being somewhat impecunious at the time, I found a used set of pistons & liners plus the cylinder head from another engine (broken piston was due to severely worn valve guides). My total outlay was under $300 ($400 if you count the spare head) and a few days of my time. Could have been less than that, but I also popped for new rings, rod & main bearings. That must've been around 1995, so the prices have gone up somewhat. But that also means I drove that motor another 100,000 miles or so and it was still running well when the car got wrecked (2005).
I have even gotten away with reusing the head gasket (when reassembling with the same block & head). Intake & exhaust gaskets can be cut from "high temp" gasket material (or they used to be available apart from the kit for under $10/pair). And while I don't recommend it, in a pinch you can use silicone RTV for a pan gasket.
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Without out some kind of scale in the picture it is a little hard to tell or even guess what those pieces are.
If they were very small, they could be a piece of the compression rings that broke off, if bigger something else. As others have said, you will have to pull the cylinder head no matter what. I would say it is almost certain you have done some kind of damage to the combustion camber, where and how much I am curious to find out though.
I am very interested to find out what they are and how they got in there.
Luckily these cars are pretty simple and basic in design so they are relatively simple to work on.
Mikey
If they were very small, they could be a piece of the compression rings that broke off, if bigger something else. As others have said, you will have to pull the cylinder head no matter what. I would say it is almost certain you have done some kind of damage to the combustion camber, where and how much I am curious to find out though.
I am very interested to find out what they are and how they got in there.
Luckily these cars are pretty simple and basic in design so they are relatively simple to work on.
Mikey
OP
RedTR3
Jedi Trainee
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OK, now the head is off and we still have a mystery! The mechanic found one more piece of metal in the #4 cylinder (In addition to the 2 pieces that I pulled out with magnet). But he cannot see any issues or missing parts in the head. The cyliner bore looks good and there are a couple of small dings on the piston top that he hopes to be able to smooth out.
He is sending the head to the machine shop along with the metal pieces for further evaluation. If the machine shop finds nothing wrong with the head then we may just put it back on and try it - we'll see what the machine shop recommends....
He is sending the head to the machine shop along with the metal pieces for further evaluation. If the machine shop finds nothing wrong with the head then we may just put it back on and try it - we'll see what the machine shop recommends....
CJD
Yoda
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Well...good news! At least the damage was minimal. You might try shaking the exhaust system to see if some of the FOD blew out the exhaust.
Is there a chance some little part fell in the air cleaners while they were off? Another post today has a gentleman who used his cleaners to hold the small parts while he worked. A couple washers got left in the cleaner when it was put back on and he lost 2 pistons from it. I think it would be most likely that something dropped in your air cleaner undetected.
I'm excited for you that there was no major damage!
John
Is there a chance some little part fell in the air cleaners while they were off? Another post today has a gentleman who used his cleaners to hold the small parts while he worked. A couple washers got left in the cleaner when it was put back on and he lost 2 pistons from it. I think it would be most likely that something dropped in your air cleaner undetected.
I'm excited for you that there was no major damage!
John
TR3driver
Great Pumpkin - R.I.P
Offline
Some years ago, my Dad was at one of his customer's shop when someone brought in a Lotus that was just barely running. Dad's customer refused to look at it (it was a body shop), so Dad took a look. No idea how it got there, but they found a 5/16" bolt laying in the throat of one of the SU carbs! After removing the bolt & a quick "by ear" mixture adjustment, the owner said it ran better than it had in years.
Anyway, glad the damage is not serious. Be sure to check inside the intake manifold before you put it back together.
Anyway, glad the damage is not serious. Be sure to check inside the intake manifold before you put it back together.