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Compression build up

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Old 06-10-15, 07:30 PM
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Compression build up

How long does it take for a rebuilt 13b to build compression. I heard its normal for a rebuild to have lower compression, but mine won't start with out being pulled. Once it's on it runs good but I'm wonder if I have a bad build I can almost never get it to start by turning the starter.
Old 06-10-15, 07:38 PM
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what car?

have you confirmed where the timing is while it's running? another idea is to do a compression test after it's run and warm.
Old 06-10-15, 07:39 PM
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Did you test the engine to see what the actual compression is?
Normally it takes a couple 100km's to get everything properly settled.
Your compression numbers will come up as everything wears to where it should be,but it won't be a drastic change in Numbers..like if you start off with 50 and think that the numbers will end up as 110 then there is something askew.
BTW..50 is just a number for reference.If you rebuilt and tested at 50 then you would not have rebuilt the engine correctly and would need to address it
Old 06-10-15, 08:11 PM
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Timings good compression is 60 not much better than 50. I'm pretty upset. I was told this is all normal with these cars.
Old 06-10-15, 08:11 PM
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Originally Posted by nasty
How long does it take for a rebuilt 13b to build compression. I heard its normal for a rebuild to have lower compression, but mine won't start with out being pulled. Once it's on it runs good but I'm wonder if I have a bad build I can almost never get it to start by turning the starter.
i've had a few go 20-50 miles before starting on their own, most start right away.
Old 06-10-15, 08:48 PM
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Originally Posted by nasty
Timings good compression is 60 not much better than 50. I'm pretty upset. I was told this is all normal with these cars.
that is not that good, it may run, but I bet it doesn't have much power. even after a fresh rebuild you should have at least 100 psi

you could keep driving it and see what happens, but I wouldn't have very high hopes
Old 06-11-15, 01:01 PM
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what new parts went into your rebuild?
Old 06-12-15, 09:50 PM
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New side seals and springs. Apex seals and springs. Corners seals. Thermal pellet and new seals.
Old 06-12-15, 10:29 PM
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Compression build up

how were the housings is the next question?
Old 06-12-15, 11:59 PM
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Originally Posted by lduley
how were the housings is the next question?
I replaced one housing and rotor the other looked like it was in good condition.
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