Author Topic: Checking Compression  (Read 109 times)

Offline Nhaislip

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Checking Compression
« on: May 10, 2020, 05:56:52 pm »
I checked the compression in my sons red plate small fan engine. Car runs great and is fairly quick but not as quick as we would like.

Question is do you use the kPa or inch pounds?  Inch pounds it?s around 30. Around 195 on kPa. I?m confused lol. I was told it should be between 190-230 and cylinders within 10 of each other. If it?s accurate at 30 we need a serious rebuild!

Thanks!




Offline justfreaky

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Re: Checking Compression
« Reply #1 on: May 10, 2020, 07:10:14 pm »
Looking through some old threads for you and doing a bit of research. I gleaned this information:
The engine defiantly needs to be warm for the compression check. Also make sure the throttle is wide open too.
Make sure your valve lash is correct. I read in the older thread that having the valves adjusted too tightly will cause a drop in power, but what is the effect of having the adjustments too loose? My intake valve lash is between .007-.008 on all of the valves, will this decrease power as well? I know that back in our bando days guys would set the valve lash tighter for longer tracks to gain top end power and wider for shorter tracks for low end power.
Yes, cylinders should all be within 10% of each other.

I will do some other searching and see if I can find anything else for you.

Welcome to the site!

Steve
Better to be hated for who you are, Than to be loved for who you are not.


Offline Nhaislip

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Re: Checking Compression
« Reply #2 on: May 10, 2020, 09:57:16 pm »
Thanks Steve. I appreciate it!

 

anything