CM570 compression in fuel

[Rawze]

Things that come to mind...

* Bad Injectors.

* Leak in fuel lines.

* Cracked or worn out head.

* Bad fuel pump that is sucking air (but highly unlikely).

It is normal to get some bubbles into the return line. It is due to cavitation at the regulator. -- It will typically stop if you apply a bit of back-pressure/restrictions to the return fuel line system while testng.

Pressurize the fuel tanks to 10 psi and see if it clears up, or if you find fuel seeping out of one of the fittings,.. pump, etc. while engine is off and it sits for an hour or so with tanks pressurized.

WARNING: -- NEVER -EVER try to remove the fuel caps woth the fuel tanks pressurized. THEY HAVE TREMENDOUS FORCE BEHIND THEM, and will break your arm.wrist if you try to remove them with the tanks pressurized even a little bit. The pressure volume of the whole fuel tank is behind them.


Have you boroscoped the engine while the injectors were out? -- Check for cracked valves, head, and signs of washed out cylinder walls or washed out carbon ring.

Also check temps at exhaust ports. that will usually reveal a lot too, and run the engine on only one cylinder at a time to see how it does.