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Damaged piston


Reg Evans

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Yes, I know about the rare 2 bbl intake being rare.  I installed it on my engine cause I wanted to try a 2 bbl carb.  The 2 bbl carb I had made the engine run like crap and another one I had required me to modify the linkage.  So, instead of removing that manifold and putting the original 1 bbl manifold back on I just installed a 1 to 2 adapter up side down.

The exhaust manifold is a Tom Langdon reproduction of a Fenton.

Update....I bought this set of pistons,pins and rings.  Total cost after coupon discount was $153.

The engine is gonna get 6 new pistons !

http://www.ebay.com/itm/SEALED-POWER-Chrysler-Dodge-Plymouth-218ci-230ci-Pistons-Rings-1933-60-060/151993173318?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

 

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6 hours ago, Reg Evans said:

Yes, I know about the rare 2 bbl intake being rare.  I installed it on my engine cause I wanted to try a 2 bbl carb.  The 2 bbl carb I had made the engine run like crap and another one I had required me to modify the linkage.  So, instead of removing that manifold and putting the original 1 bbl manifold back on I just installed a 1 to 2 adapter up side down.

The exhaust manifold is a Tom Langdon reproduction of a Fenton.

Update....I bought this set of pistons,pins and rings.  Total cost after coupon discount was $153.

The engine is gonna get 6 new pistons !

http://www.ebay.com/itm/SEALED-POWER-Chrysler-Dodge-Plymouth-218ci-230ci-Pistons-Rings-1933-60-060/151993173318?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

 

Something caused that cylinder to run lean and overheat. I'd make sure I knew what caused it before I put it back together.  

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Okay,  I'd like to know some symptoms of an engine ...."running lean"

Cause this  particular engine ran smooth at idle,  Had a nearly instant throttle response, and lots of power.  I could shift into 2nd gear 1/2 way up  my very steep road (16% slope)

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5 minutes ago, Reg Evans said:

Okay,  I'd like to know some symptoms of an engine ...."running lean"

Cause this  particular engine ran smooth at idle,  Had a nearly instant throttle response, and lots of power.  I could shift into 2nd gear 1/2 way up  my very steep road (16% slope)

Well engine can run hot, manifolds could end up being red hot, backfiring, popping on deceleration.

Sluggish, but possibly running better at higher altitudes...

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4 minutes ago, 55 Fargo Spitfire said:

 

Sluggish, but possibly running better at higher altitudes...

Hmmm,your theory is an engine will run less lean at high altitudes due to the thinner air?

I had never thought about that,but you might be right. It's interesting to think about,anyway.

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42 minutes ago, Reg Evans said:

Okay,  I'd like to know some symptoms of an engine ...."running lean"

Cause this  particular engine ran smooth at idle,  Had a nearly instant throttle response, and lots of power.  I could shift into 2nd gear 1/2 way up  my very steep road (16% slope)

How many symptoms do you need? You've had two people tell you that it looks like a burnt piston. The symptoms you have, burnt piston and collapsed ring lands; indicate that the cylinder ran lean. If you think the piston just decided life wasn't worth living and decided to self-destruct; go ahead and put a bunch of money and new parts in it and hope it won't happen again. In fact, I suggest you do exactly that. 

Edited by MackTheFinger
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13 minutes ago, knuckleharley said:

Hmmm,your theory is an engine will run less lean at high altitudes due to the thinner air?

I had never thought about that,but you might be right. It's interesting to think about,anyway.

It's a given. Less oxygen=richer mix. 

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46 minutes ago, MackTheFinger said:

It's a given. Less oxygen=richer mix. 

I realize that,but just because it seemed so obvious to you doesn't mean it wasn't a revelation to me. I live in the flatlands,so it should be no surprise I don't think much about altitude  issues.

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1 hour ago, MackTheFinger said:

How many symptoms do you need? You've had two people tell you that it looks like a burnt piston. The symptoms you have, burnt piston and collapsed ring lands; indicate that the cylinder ran lean. If you think the piston just decided life wasn't worth living and decided to self-destruct; go ahead and put a bunch of money and new parts in it and hope it won't happen again. In fact, I suggest you do exactly that. 

Now now, Reg is on fact finding mission, no reason to get impatient.

I think Reg knows what he has to do to fix this up, he has been playing with these Mopar flatheads since 1965......

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2 hours ago, Reg Evans said:

Okay,  I'd like to know some symptoms of an engine ...."running lean"

Cause this  particular engine ran smooth at idle,  Had a nearly instant throttle response, and lots of power.  I could shift into 2nd gear 1/2 way up  my very steep road (16% slope)

A lean engine will usually have symptoms like... it will be cold natured, it will like the choke a bit more as it lessens air and richens the mixture. If it backfires it will be through the carb. It may run hotter. Sometimes they will not idle well or the carb adjusted out of spec to get it to idle.  Back when you could "read " plugs ( they say you can't now due to the additives in fuel ) a lean  engine's plugs would be white, properly adjusted mixture would burn a tan, black would be rich. Leaner engines will be more responsive but so will one that's adjusted right vs too rich. Also they will seem to surge.   I've worked on a few motorcycles over the years and one thing I've noticed. The last few years Harleys offered a bike with a carb ( think '05 on the big twins ) owners complained about how cold natured the bikes were. They had them leaned to the max from the factory to get them past emissions. Same symptoms will show on your car or truck but don't over scrutinize this, some engines are just naturally cold natured. Things that can cause one to run lean, carb issues, base gasket or intake leak, vaccum leak,  ignition  timing being off, wrong heat range on your plugs. Prob a few other things but that's what comes to my mind.

  Really, in my experience, anytime an engine ran lean enough where it would damage something the symptoms were pretty obvious and just ignored or there were other factors. Yea I would go over it with a fine tooth comb and check it all out but don't you always when you rebuild one? Good luck, hope she's twice as strong this go around.

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9 hours ago, MackTheFinger said:

How many symptoms do you need? You've had two people tell you that it looks like a burnt piston. The symptoms you have, burnt piston and collapsed ring lands; indicate that the cylinder ran lean. If you think the piston just decided life wasn't worth living and decided to self-destruct; go ahead and put a bunch of money and new parts in it and hope it won't happen again. In fact, I suggest you do exactly that. 

Wow Finger....thanks !  Now I know for sure that the engine has been running too lean and I'm an idiot.

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23 minutes ago, Reg Evans said:

Wow Finger....thanks !  Now I know for sure that the engine has been running too lean and I'm an idiot.

Wow right back at you.. I didn't call you an idiot and won't now but for some inexplicable reason you tore down what was by your accounts a perfectly running engine and found a burnt, scuffed piston with collapsed ring lands. Pistons burn and ring lands collapse because they've been overheated. Your machinist told you the damage was caused by overheating. Have you told him he was wrong, too? I offered my opinion in good faith but I'm always looking for enlightenment. Have you come up with another reasonable explanation for the damage other than the errant wire brush fragment theory? 

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9 hours ago, 55 Fargo Spitfire said:

Yes, and if it's already running leaner, it may combust better at higher altitudes I suppose.......

Right on. If a carbureted engine runs perfectly at sea level it'll run poorly at 6,000 feet due to the decrease in oxygen. Most engines aren't optimally jetted so it's not always severe enough to be noticeable. Computer managed, fuel injected engines vary the mix so it's not an issue with them.

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9 hours ago, knuckleharley said:

I realize that,but just because it seemed so obvious to you doesn't mean it wasn't a revelation to me. I live in the flatlands,so it should be no surprise I don't think much about altitude  issues.

I didn't mean to give the impression I was trying to bust your chops and I apologize if it seemed that way. You give a lot of good advice and seem to have less ego than some. I was taught to envision fuel mix issues by thinking about an oxyacetylene torch. Spark it up with just the gas turned on and it'll blubber and smoke until you give it some oxygen. The more oxygen you give it the hotter it gets, right up to where it'll melt steel.

In my opinion that's what happened in the Zen Master's engine. Somehow there was more oxygen introduced into the cylinder, the piston got red-hot and expanded enough to decrease the clearance until the piston scuffed. I suspect there was some detonation or the ring lands wouldn't have been hammered. It's a reasonable explanation until a better one comes along. :)

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10 hours ago, 55 Fargo Spitfire said:

Now now, Reg is on fact finding mission, no reason to get impatient.

I think Reg knows what he has to do to fix this up, he has been playing with these Mopar flatheads since 1965......

I appreciate what you're saying with a few caveats. First, I started playing guitar about 1965 and still don't feel that I really know what I'm doing. I treasure constructive criticism and advice to better inform and make me a better guitarist. The same can be said for my mechanical abilities. I still learn from my own and others mistakes. Second, I've hired more than one person to work for me who had 20-25 years experience but apparently, just as with some of the mistakes I continue to make; they just did the same thing over and over and over. A third caveat is that I've worked on many vehicles that had problems the owner never noticed. I think some of these problems came on gradually and only became evident when either someone else drove the vehicle and noticed the problem or there was a catastrophic event like a  collapsed, burnt piston. :)

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37 minutes ago, Don Coatney said:

Just a thought. If the engine was running lean why was only one piston affected? The same fuel mixture is delivered to all cylinders.

The same fuel mixture is NOT necessarily delivered to all cylinders. There's one intake port per cylinder or there could be a leak between the head and any particular cylinder, neither of which would affect the other cylinders. Since the head had been removed prior to this problem that's where I'd look first. In the absence of any other evidence an overheated, burnt piston with collapsed ring lands supports the theory of a lean fuel mixture. 

Edited by MackTheFinger
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40 minutes ago, Don Coatney said:

Just a thought. If the engine was running lean why was only one piston affected? The same fuel mixture is delivered to all cylinders.

Yes, and the scuffed piston is #1. Wouldn't #6 be the first to go since it is always the hottest running part of the engine when everything is correct.

Here's a photo of plugs running lean ,perfect and rich and here's a photo of mine. If anything mine are leaning a little to the rich scale.

My engine never showed any of these symptons.  NOTE:  The machinist did say that it was odd that there was only damage to one side of the piston and not the other.

1: Bad Performance

Your car will have less power than it had before. For example, this may manifest itself in sluggish acceleration, at certain RPMs, or a general lack of power from your car. This is a result of less fuel in the ignition chamber than the car’s computer expects, and the power generated by the engine will be lower than usual. If you car is running extremely lean, you can sometimes even experience backfires, or popping when decelerating.

2: Car Won't Start

Your may have trouble starting your car, or your engine may not turn over. This is because your initial ignition may not be enough to sustain combustion, or your engine may not have enough power to cause the crankshaft to turn, causing it to get stuck.

3: Spark Plugs Are Clean Or White

A common symptom of your car running lean is that your spark plugs are clean or turn white. Spark plugs are generally a brown or grey color, which is caused by normal ignition. However, your spark plugs will become either too clean (evidenced by a lack of normal color) or white when your engine is running significantly lean.

1 spark 1.jpg

1 sparks 2.jpg

Edited by Reg Evans
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There is one intake port for every two cylinders on the 23 and 25" flatheads..

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21 minutes ago, MackTheFinger said:

Enlighten me, Reg. What's your theory?

I haven't formulated one yet,Mack.  Still gathering info. My mechanic friend thinks it may be a bent rod.

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