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Discussion Starter · #1 ·
Ok here goes, i changed the head gaskets on my thundercat..its a 99 1000 triple.....the old o rings were pretty smashed , cleaned the area up good put new gaskets on replaced the heads, when we tryed to start it up, it wasnt cooperating, then it back fired and scared the wholey be jesus out of me..lol and after a few pulls it stopped dead on the pull rope and damn near yanked my arm outta socket....took the heads back off to see if there was something wrong, nothing visible that i could see, pulled it over slow with the tops of the heads off, all pistons seemed to be firing and moving the way they should...replaced tops again and torqued down, fired over once and then backfired and for some reason just flat ass wont start....did i do something wrong, did it maybe foul the plugs??? what should i try next...any help would be great..and thx in advance
 

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pigpensthunder said:
Ok here goes, i changed the head gaskets on my thundercat..its a 99 1000 triple.....the old o rings were pretty smashed , cleaned the area up good put new gaskets on replaced the heads, when we tryed to start it up, it wasnt cooperating, then it back fired and scared the wholey be jesus out of me..lol and after a few pulls it stopped dead on the pull rope and damn near yanked my arm outta socket....took the heads back off to see if there was something wrong, nothing visible that i could see, pulled it over slow with the tops of the heads off, all pistons seemed to be firing and moving the way they should...replaced tops again and torqued down, fired over once and then backfired and for some reason just flat ass wont start....did i do something wrong, did it maybe foul the plugs??? what should i try next...any help would be great..and thx in advance
Why did you change your o-rings in the first place?
 

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Discussion Starter · #3 ·
i changed the o rings, because i bought the sled, and after rode it, i noticed i used half a tank of coolant, couldnt find any puddles in the pan, looked closer and noticed that there were tracks going down the back of the heads of what appeared to be antifreeze. so i decided to chang e the gaskets as a precaution to messing stuff up..
 

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you can put any plug wire on any head. They all fire every 120 degrees.

As far as the issue. If they were leaking the sled may have gotten hot at one time. When that happens you need to take the heads off and "lap" them. Get a flat surface and put some small grit paper on it and sand the head until it all starts to make contact with the small grit paper. The heads will warp when they get hot and will just keep taking out one o-ring after another. Also, when you put them on put the o-rings in the groves and start 2 bolts on opposite sides and run them all the way down to hold the head in place. Then you add the other bolts. Make sure the cylinders have all of the anti freeze out of them. Pull it over with the plugs out of it and see if any comes out. You may need to put some oil down it to help lubricate it. If the compression seems too high you probably still have coolant in it or being pumped into it.
 

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polarisripper28 said:
so your saying each plug sparks three times every rotation. that doesnt sound right.
I am 110% sure of this. He can take his plugs out, place them on a head bolt and pull the sled over and all 3 plugs will fire at the same time every 120 degrees. I rewind stators for 1990's cats so I KNOW what I am talking about.
 

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sounds like you still have some antifreeze in the case.... take it apart, get some kind of suction system and suck it out.
 

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Discussion Starter · #11 ·
MANY THX FELLAS, MY COMPUTER TOOK A CRAP SO I COULDNT REPLY FASTER...I DID CHECK THE PLUGS INDIVIDUALLY AND they were definitely fouled out..as in no dang spark..didnt think about checking for antifreeze left over..love this site..thank you everyone for the answers..i appreciate it.. as for the compression being to high..it did damn near yank my arm outta socket so i better check that too...again thx for the help
 
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