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Low compression, should i rebuild?

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Old Mar 15, 2017 | 09:11 PM
  #1  
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From: Elma washington
Low compression, should i rebuild?

Hey i recently aquired an 85 gsl and i was told it didnt run and wouldnt go over 10mph. Well i got it home and it runs snd drives just fine but i noticed the compression was low like 75psi on each rotor and 10psi per rotor face. Is it safe to drive this the way it is or doesnit require a rebuild?
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Old Mar 15, 2017 | 09:12 PM
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do the test correctly, without the schraeder valve in the hose.
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Old Mar 15, 2017 | 10:04 PM
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From: winter haven
The engine my have a lot of carbon build up in it. If so it can cause low compression from Seals getting stuck. I have seen
a 85 13b 6 port get damage from this. But if you like the car why chance it? To me there is only one way to know it's good thats to rebuild it.
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Old Mar 17, 2017 | 06:53 PM
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welcome to the board.

yes, i agree with post 2. make sure you conduct the test correctly. you mentioned that it ran and drove "just fine" when you got it home, so i am a tad bit skeptical until you have a test confirming low compression.
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Old Mar 17, 2017 | 10:13 PM
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i wasn't saying it didn't have low compression though, it did come back with only a 75psi cumulative figure but it's good to know where you are starting from.
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Old Mar 19, 2017 | 09:25 PM
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Hello just wanting to know how much it cost to rebuild a stock s4 engine. I am just wondering
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Old Mar 19, 2017 | 09:40 PM
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~$1k if you do it yourself, $1500+ to have a shop do it for you.


really depends on the condition of your existing engine as well.
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