VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1912-1928 School is in session

We'll take a vacation until the piston, rod, and pin are investigated by the manufacturer. What, with holiday, slow shipping, reluctance to make a decision, ect, it may be several days till we start school again. Don't worry, we will continue untill the case is solved. Now go out and play in the schoolyard, but be CAREFUL. (AND CONTINUE TO WORK WITHOUT THE CAPS).

We can't go play in the school yard....at least those of us in Eagle Point, Oregon.....because the Eagle Point Junior High School burned to the ground two days ago. Now, there are 750 junior high students without a school and the new school year starts on Tuesday. Looks like a long recess! :( :( :( :( :( :(

We are sorry to hear that JYD, Kids need a good place to learn and Taxpayers, teachers and parents are the ones that have to bear the burden of a terrible accident like a fire, was it caused by the wild fires or was it unrelated to those?

Most of the school was attached to the Gym which at one time was an airplane hanger that was used in WWII. The hanger was moved to Eagle Point from Camp White (a WWII military base near Eagle Point) after the war and coverted to a Gym. They think that the fire was caused by a faulty electrical panel located in the Gym, and when the Gym caught fire (at 4:00 AM), the other buildings that were attached to the Gym went with it. The fire stopped at my wife's class room which had a firewall. Her room and three other rooms of the main complex were saved by the firewall. It was a three-alarm fire with some fire trucks responding from 30 miles away, and the buildings burned most of the day. :eek: :eek: :( :( :( :( :(

I's Here!

ATTENTION everyone. School is back in session. Gather up all those kids out in the school yard and take your seats.


When we last dismissed the class we had shipped the piston, rod and pin off for identification and evaluation. That mission has been accomplished. Go to this location for the identification of the manufacturer and return to your seat.

http://www.vccacolumbiariverregion.org/chatimages/chatray4.jpg



I think that is a firm indicator of the manufacturer.

This next picture is a view of the piston pin boss nearest the firewall. Note that the casting appears to have 'sponged' in this boss. The other side of the piston reveals normal wear and no damage. Material in the damaged boss has transferred to the piston pin and attempted to 'freeze' the pin, however that never did happen. Go take a look and return.

http://www.vccacolumbiariverregion.org/chatimages/chatray1.jpg



This next picture is of the end of the pin that received the damage. Note the buildup of material on the pin. Go look and return.

http://www.vccacolumbiariverregion.org/chatimages/chatray6.jpg



This last picture is the side of the piston facing the firewall and the side of the piston that had the damaged boss. Go look and return.

http://www.vccacolumbiariverregion.org/chatimages/chatray2.jpg



The rear (firewall side) of the cylinder was scratched. This area was honed out and would be considered servicable.

As noted in another post I contacted the piston manufacturer to obtain a single piston and set of rings. Short version: They won't make a single piston. They will do a set: $600.00, rings are ONLY $80.00, time frame, about the same as the construction period for the Golden Gate Bridge.

At this stage of the game the engine is coming out of the car. It will be totally disassembled, hot tanked, and thoroughly inspected. While the engine is out the engine compartment will be detailed, a new wiring harness installed, and adjustments made as to body and radiator shell fit.

Depending upon the results of the detailed inspection of the engine it will receive new pistons, with cylinders bored out and fitted to each new piston. Rods most likely will be inserted. Other work will be done as necessary.

This will conclude the 'school'. Progress on the rebuilding will be posted only if there is an interest in it.

Final grades will be posted in the hallway within one week. Suggest you retain your notes for future reference. Have a great vacation.

Well I'm going to help Ray out with the pictures since they are on the web page that I run. And I see an error on the address that I made up for his pictures. You really need that space in the address but for some reason Bill's chat page does not like the space. Sorry for the problem.

OK, Now I've taken the space out of the address and everything should be working!

First picture should look like this:

Link to larger picture 1:
http://www.vccacolumbiariverregion.org/chatimages/chatray4.jpg

Second picture should look like this:

Link to larger picture 2:
http://www.vccacolumbiariverregion.org/chatimages/chatray1.jpg

Third picture should look like this:

Link to larger picture 3:
http://www.vccacolumbiariverregion.org/chatimages/chatray6.jpg

Forth picture should look like this:

Link to larger picture 4:
http://www.vccacolumbiariverregion.org/chatimages/chatray2.jpg

A great big THANKS to 32 confederate for staying up late and assisting in the posting of the pictures in my last post. Couldn't have done it without him.

Hey Teach,
Thanks for the lesson. Notes put into hermetically sealed container with inert gas pad.

Sure says a lot about standing behind your products. Way way behind.

hey teacher, Im the kid in the back of the room that was shooting spit wads at chipper, the bugle player, please dont end the school session so soon, as I played hookey the last two weeks. teacher, what I want to know is, will you resleeve the the engine or will you bore it. where will you get the pistons and will they be cast iron or aluminum. :) :)

CHEVY

"Depending upon the results of the detailed inspection of the engine it will receive new pistons, with cylinders bored out and fitted to each new piston. Rods most likely will be inserted. Other work will be done as necessary."

Pistons will be aluminum and will be purchased from my local parts house. Clearance will be as specified by the manufacturer.

HEY TEACHER, HAVE YOU PURCHASED ALUMINUM PISTONS BEFORE?? IT SOUNDS LIKE THERE IS NOT SO GOOD OF ONES BEING SOLD ON THE MARKET TODAY. WHEN YOU REBUILD THE ENGINE, ARE YOU DOING IT ONE HUNDRED PERCENT OR ARE YOU JUST DOING ENOUGH TO GET IT BACK ON THE ROAD.?? :) :) :) :)

I always use aluminum pistons in all rebuilds. Modern pistons as a rule do not cause any undue problems.

The engine will be totally rebuilt with replacement parts as necessary and will employ several upgrading methods.

Will you chamf/ radius lower skirt edge of new pistons?
Sharp edge can cause load on cast iron causing failure.
chev v-6 problem was solve in1995. All new piston incorp. this .. Engine running past 60,000 were ok others failed. A friend of mine solved this problem. got paid good.
REX

I think posting the step by step process of the rebuild as it takes place will be both interesting and educational. KEEP IT GOING

Hi coope,

No, I will not modify the pistons in any way. I am using MODERN pistons and don't want to void the warranty. The pistons are aluminum/modern alloys.

Hand raised. Mr. Professor, Mr. Professor! You can tell I'm new to this school because my service manual is not very greasey yet. Is it still your professional opinion that the cause of failure was "crude" low quality components used in the last rebuild? Do you believe lubrication has been adequate? :confused:

My humble opinion would also lean toward a lubrication problem.The unknown is how tight the pin was,was engine driven too fast while fresh,run low on oil or overheated.The material transfered from the piston to the pin and ripped off the piston indicates extreme heat due to lack of lubrication.Was piston fit too tight in cyl.?????If it is, skirt scuffing usually results.We will never know for sure as to what caused the problem but its fun to speculate.

HI CHEVGENE, IF THE LUBRICATION WAS OK, THEN WHAT DAMAGE WOULD BE DONE BY OVERHEATING. ANOTHER THING I HEAR IS PISTON COLLAPSE, WHAT EXACTLY HAPPENS WHEN YOU HAVE PISTON COLLAPSE. THANKS :confused: :confused: :confused: :confused:

Now I'm glad you asked that question. (that is what speakers always say when asked a question that they don't have an answer for) I have heard the term used many times and can't say that I have actually seen a collasped piston in my 50plus years of looking under hoods.I would assume ( and we know what that can stand for) that a piston subjected to extreem heat will have the skirts deform causing it to be a loose fit in the in the cylinder.That is the best that I can come up with.....What the great pictures of Ray's piston shows me is that extreem heat was present causing aluminum to heat up and melt.This could have been caused by something that I mentioned in my previous post and the alloys (or lack of) in the piston could not tolerate.The picture of the wrist pin indicates that it was so hot that it turned blue.That also goes back to the clearance mentioned so often,wether its piston or bearing clearance it should be refered to as OIL clearance because this will be the amount of room for the oil film so if things get so heated and there is no room left for oil lubrication fails,there is metal to metal contact, and the friction causes heat and things melt.That is what causes a bearing to "burn out" pistons to "score" and al kinds of nasy things......I still respect
Ray's opinions as he is familiar with the four cyl. engines and can see his first hand although the pictures are great.Amen

Yep, well stated Grasshopper, I Mean Chevy Nut.

THANKS CHEVGENE, FOR YOUR COMMENTS, YOUR EXPERTISE ON ENGINES ARE A GREAT ASSET TO THIS VCCA CHAT SITE. THANKS FOR ALL YOUR INFORMATION. I JUST WISH I COULD HAVE MY ENGINE SITTING ON YOUR WORK BENCH. I WOULD THINK THAT ALOT OF GUYS WHO USE THE TERM PISTON COLLAPSE, REALLY DONT KNOW EXACTLY WHAT THAT TERM MEANS. CHEVGENE, WOULD YOU THINK THAT WITH EXTREME HEAT AT THE WRIST PIN, THAT THE CLEARANCE TOLLERANCE WOULD CHANGE CAUSING IT TO LOOSEN AND CAUSE PISTON SLAP. ALSO WHEN YOU TALK ABOUT PISTON SLAP ARE YOU SAYING IT IS AT THE SKIRT OF THE PISTON WHERE THE KNOCK HAPPENS. THANKS FOR YOUR COMMENTS :) :) :) :)

Piston slap is the result of the piston rocking back a forth in the cylinder. If the fit is too loose the skirt will hit the cylinder wall one or more times on its trip up and down. It is like tapping on the inside of the cylinder with a hammer. The amount of force from the exploding gas/air mixture and resistance of the piston pin/piston also affect the force of the slap. There also will be some engine speeds that are worse than others. To go into all the dynamics gets a bit complicated.

Though not good and eventually damaging. Piston slap will not typically cause too much damage in a short time.

Chip answered the piston slap question well but with Rays piston and wrist pin problem it is hard to say as to which thing failed first or what caused either to fail.I would say that NEITHER was caused by piston slap.The other thing is that he has found no dammage on the other pistons.When overheating is a cause there will usually be problems with more than one piston.No, you wouldn't your engine on my bench.It would never get done.While listening to all of this I have my own problem waiting for me in my garage.Two years ago my '34 developed an engine noise.It was very slight at the beginning,could short it out on #1 cly. so I dropped the pan and check conn. rod clearance.Everthing was OK.What I could see of piston & cyl. wall looked OK buy noise was still there.Although I have driven it very little since the noise has become louder so the next thing is to pull the aluminum piston,And although anxious to do so just haven't found the time .The pistons are NORS replacements of a old name brand.The engine is bored .040" over and I do have another set to work with.The way things look it may be next years project.(thats what I said last year)

THANKS CHIPPER AND CHEVGENE, SINCE I CANT TAKE THE ENGINE OVER TO GENES WORKBENCH, THE NEXT BEST THING TO DO, WOULD BE TO TAKE IT TO CHIPPERS WORKBENCH, BUT THE ONLY THING CHIP WOULD DO IS TO GET OUT HIS OLD BEAT UP BUGLE AND PLAY TAPS TO MY ENGINE??????IS THAT RIGHT CHIP. :arrow: :arrow: