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Compression test

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Zxninja
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Compression test

Post by Zxninja » Thu Jan 16, 2020 7:51 pm

Hi guys
I’ve had my RX8 since May last year and have done nothing to it except change the oil and filter.
It runs great,I’ve not had any problems with hot/cold starts but I’ve never had a compression test done on it.
Do you think it’s worth while to get one done?
I’m thinking of changing plugs/leads and coils but before I spend that amount of money I’m thinking of checking the compression for peace of mind.
What would you guys do? :-k

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Re: Compression test

Post by qwakers » Thu Jan 16, 2020 7:53 pm

well look at it like this...

you have a compression test done. that has one of two results.

its fine, youre happy, just as before, that your engine is healthy. your engine either lasts ages or blows up tomorrow.

its very low, and you're depressed, the car is worthless, you keep driving it, your engine either lasts ages or blows up tomorrow.

if you don't have a compression test done this only has one result.

your happy, your car appears healthy, you have lots of fun, your engine either lasts ages or blows up tomorrow.


:D
These users thanked the author qwakers for the post (total 7):
bigpete (Thu Jan 16, 2020 7:56 pm) • Vj4sothername (Thu Jan 16, 2020 8:00 pm) • Zxninja (Thu Jan 16, 2020 8:42 pm) • ChrisHolmes (Thu Jan 16, 2020 8:44 pm) • nightfire10 (Thu Jan 16, 2020 8:49 pm) • geofftl1000r (Thu Jan 16, 2020 9:27 pm) • New Duke (Thu Jan 16, 2020 9:31 pm)

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Vj4sothername
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Re: Compression test

Post by Vj4sothername » Thu Jan 16, 2020 8:00 pm

Schrödinger's compression... I am also leading this life.
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Re: Compression test

Post by Zxninja » Thu Jan 16, 2020 8:42 pm

qwakers wrote:
Thu Jan 16, 2020 7:53 pm
well look at it like this...

you have a compression test done. that has one of two results.

its fine, youre happy, just as before, that your engine is healthy. your engine either lasts ages or blows up tomorrow.

its very low, and you're depressed, the car is worthless, you keep driving it, your engine either lasts ages or blows up tomorrow.

if you don't have a compression test done this only has one result.

your happy, your car appears healthy, you have lots of fun, your engine either lasts ages or blows up tomorrow.


:D
When you put it like that.......... :thumleft: :D :D

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ChrisHolmes
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Re: Compression test

Post by ChrisHolmes » Thu Jan 16, 2020 8:45 pm

A compression test can show up a much more than just overall low compression. It is possible to diagnose a broken side seal or apex seal before major damage occurs.
It is amazing how much damage a rotary can with stand without any rattles or other obvious symptoms so a compression test can be very useful.
There may be a member near to you with a compression tester who can do the test far cheaper than a Mazda dealer.
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Re: Compression test

Post by Velocity_Dan93 » Thu Jan 16, 2020 10:03 pm

I’m in rugeley and happy to help out with a compression test :)
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Re: Compression test

Post by Secla » Thu Jan 16, 2020 10:48 pm

unless you plan on rebuilding it if its low comp then maybe best to live is blissful ignorance and make sure your breakdown covers up to date

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Re: Compression test

Post by Velocity_Dan93 » Fri Jan 17, 2020 12:12 am

Secla wrote:
Thu Jan 16, 2020 10:48 pm
unless you plan on rebuilding it if its low comp then maybe best to live is blissful ignorance and make sure your breakdown covers up to date
Good plan if you don’t rely on it daily. Better to know me thinks. At least then you can but arrangements in place or start to plan a build a little in advance
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Re: Compression test

Post by warpc0il » Fri Jan 17, 2020 12:43 am

I was going to suggest that it's like avoiding medical tests, as many people would "rather not know" but this means that you can't know to change you're lifestyle, or have an operation that might save your life.

However, the analogy falls down as "resurrection" isn't a viable option, at least for most of us... :shock:
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