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PISTON RINGS TOO TIGHT ?


1955chevy33

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OK,fellow smart racers. I had a sbc built for my dirt car. We used the total seal max seal gapless ring set. I put it in last week and ran it for about 20 minutes for break in.

The temp got up to about 200 . I turned it off and tried to restart it. The engine would only turn a half a round. I am using hi torque reduction starters . I figured the starter was getting old so I pulled a new one out and same thing. I put a second battery on the car and battery charger on boost setting. It would spin about 3/4 of turn each try .

After it cooled off,it started great. I let it run again for about 20 minutes and shut it off,same thing.

I was thinking something was too tight. I mentioned it to my engine builder and he called total seal. He then told me they said for stock cars the gap needed to be about .022-.028 and my builder had set my gaps to between .006-.009. .

I am aware of the potential to take the top off my pistons if I just go out and race it the way it is.

MY QUESTION; Any suggestions on a way to wear out the rings or cylinder walls enough to get the clearance? In other words any fixes without the obvious taking the engine back out and starting over ? Freddy

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Freddy,

You sure the timing isn't too far advanced? if so it may do that i can't hear it so not sure exactly what its doing. If it was built to the wrong specs take it back, any short cuts are only gona cost you in the long run. I know this sucks but better now than have it bust the top ring out of a piston due to the rings, then take out a cylinder wall and a head, and with my luck the cam and crank.

call me sometime to catch up, mis talking to you.

joe

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Hey Joe. Yea,the engine builder wants me to bring it back. I am just so sick and tired of pulling engines. Everytime I pull one before it blows to save it for future use. I find out its not useable and have to go build another one. The bad thing is,the engines were running fine and winning before pulling them out.

 

This is one of the new engines and it sounds good and strong.I am pretty sure its not too much compression or timing. Its definately seems like it gets too tight after getting above normal temp. I dont know what normal clearance is on piston rings for dirt track cars but evidently .006-.009 is too small a gap.

 

I will probably pull it,send it back and keep sitting out races ! I hope your doing good with your new car !

TTYL,Freddy

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as much as it cost to build a motor ...this is our motto and we live by it .....WHEN IN DOUBT .PULL IT OUT ..NOT EVER a question ..we wont even start one up if there is question mark ..no race is worth a motor you dont mind blowing ... .....

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I would most definetly pull it out it's not worth it and will cost you more if you don't! I don't recall the interval of ring clearance it just depends on use there are a few factors that come in when filing the rings for clearance, but .022 to .028 sounds around average.Have you checked for compression? I would like to know how much compression its putting out. I wouldn't run it though just curious.

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for an sbc with total seal top ring, the top ring gap should be a min .026 for STD .030 and .040 and around .0265 for .060 or bore X .0065 and the rail for the top ring should have a larger gap than the main ring .028 for example. But remember that a little big is always better than a little small when it comes to ring gaps.

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YEA,I KNOW,I KNOW. ALL OF YOU ARE RIGHT ! ! I WAS JUST HOPING FOR A MIRACLE CURE. I AM SOOO TIRED OF WORKING ON RACE CARS ! I AM JUST GOING TO BLOW OFF THIS SEASON AND TAKE A BREAK FROM THE CARS AND ONCE I CALM DOWN, START WORKING ON THEM SLOWLY FOR NEXT SEASON.

I AM GOING TO CHECK COMPRESSION FOR THE HECK OF IT.

ONE MORE QUESTION : I RAN THE ENGINE 20 MINUTES FOR CAM BREAK IN AND ANOTHER 15 MINUTES THE NEXT DAY.

I PERSONALLY DONT LIKE REUSING PISTON RINGS BUT SINCE THESE COST ABOUT $ 300 PER SET. DO YOU THINK THESE WILL BE SAFE TO FILE THE ENDS TO GET MORE GAP AND REUSE ?

OR DO YOU THINK THAT 35 MINUTES OF HIGH RPM HAS ALREADY HELPED SHAPE THEM TO THAT CYLINDER ?

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ive never spent that much on rings ...aboult half of that for four bangers ...i have reused rings before ..after short running ...have not had a problem ...its going to be up to a few factors ... dont know what hone clearance is do you .. ,,,.....get with the company that built those rings ....they would have a better answer i would think ,,

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There is no way to accelerate the wear - the rings would have no tension left by the time enough circumfrence was removed (you would have to reduce radius .003314 for every .001 thou gap increase). At that diameter reduction you would reduce tension proportionately.

 

You can re-use them - depending on how they were installed , removed dressed to gap and re-installed. They should hold their tension if done right (that is not "sprung" on and off. However for the cost may be better replacing em.

 

Edited: as a second thought keep in mind that rings are springs - they will lose a little (but not enough to matter) of their rate being handled. However HEAT is a different story. For example when you plug check - if you see spots on the center electrode showing pre-ignition/detonation - your rings have already suffered. They ALWAYS suffer first by losing tension - which then lets more oil (a MUCH hotter burning fuel source) in and increases the effect of the detonation. Thats when land damage occurs. Keeping that same thing in mind - the excess friction of having been run so tight may have heated them to a point of losing some of their tension. Builder should check this!

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I did the same thing .. that too tight I took my motor apart and the cylinders were blue . I trashed those rings and will never use them again and too much money went down the drain rehone it youll probley see chater markes on the walls for sure. Take it back to the one who built it

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I did the same thing .. that too tight I took my motor apart and the cylinders were blue . I trashed those rings and will never use them again and too much money went down the drain rehone it youll probley see chater markes on the walls for sure. Take it back to the one who built it
How long did you run your engine ? What were the symptoms of too tight an engine ?
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I did the same thing .. that too tight I took my motor apart and the cylinders were blue . I trashed those rings and will never use them again and too much money went down the drain rehone it youll probley see chater markes on the walls for sure. Take it back to the one who built it
How long did you run your engine ? What were the symptoms of too tight an engine ?

I used to use a torque wrench to turn the engine over after all assembled - minus spark plugs a wide clearanced race engine should turn with less than 20 ft lbs applied, a tighter street engine could be up around 35. After run in should be LOOSER - not tighter!

 

It only takes 30 seconds to heat the peaks of your honing cross hatch and start blueing em. If visably blued probably ran longer than 2 minutes.

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I did the same thing .. that too tight I took my motor apart and the cylinders were blue . I trashed those rings and will never use them again and too much money went down the drain rehone it youll probley see chater markes on the walls for sure. Take it back to the one who built it
How long did you run your engine ? What were the symptoms of too tight an engine ?

I used to use a torque wrench to turn the engine over after all assembled - minus spark plugs a wide clearanced race engine should turn with less than 20 ft lbs applied, a tighter street engine could be up around 35. After run in should be LOOSER - not tighter!

 

It only takes 30 seconds to heat the peaks of your honing cross hatch and start blueing em. If visably blued probably ran longer than 2 minutes.

These should be blued then since the engine has a total of about 35-40 minutes run time. Will honing them be enough or will the cylinders need to be bored again ? Or will the blueing matter ? I know the machine shop cut them just a hair oversize since it was a race engine.
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should be ok as long as it didn't scratch the walls, I would be more worried with tight rings that it would break one and tare some stuff up, I wouldn't be surprised if a few didn't break when the pistons were being knocked into the holes. but you outta be able to just run a ball hone through it or a glazebraker as long as it didn't tapper the cylinders... check and be sure

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