Viewing a rib tomorrow with a 40hp yamaha 2 stroke but completly forgot about testing the engine for compression
I can't sea trial so it's vital I get one
Does anyone know where I can buy one tomorrow morning? or does anyone have one that I could borrow for a few hours?
also is this right;
Disconnect fuel line
remove spark plug and screw in compression tester
turn engine over and read compression
repeat for all cylinders
what should compression should I be looking for in a 40hp Yamaha?
The compression tester I've got came from a bike shop called Hein Gericke. It came with two adapters and two universal adapters, which are rubber cones that you have to push into the spark plug hole. The universal adapters aren't ideal and will be tricky if engine is pull start but will get the job done if your stuck.
Might be worth looking for a bike store if your stuck.
Let us know how you get on and what the compression figures are. I tested my 50hp the other day but can't find any official figures on what the compression should be.
Sounds about right and as I expected. I personally would have been a little concerned at readings of 100 as that could indicate more wear to cause it to drop from new which would yeild at least 130 upto as much as 150 maybe more I'm not sure on factory specs,
but then it depends on age too and I'd rather have 3 at 100 than 2 at 130 and the 3rd on 110 etc.
I did, the engine was 2004 and sold in 2005, around 80 hours. very nice engine and average boat. nothing wrong with the boat and i can't complain considering the price!
Can't wait to test it out, got some more boating gear today all ready to brave the rain tomorrow
I finally own a rib! woohoo!