Unable to say why it's so close, but if it's Sierra it could be product issue. So long as its not touching it should be fine. If it does barely touch it should be no issue with it being plastic
I go to BAM and enter serial number on top right. If valid number it shows up and just select it and it takes you to parts list. Can also look thru by finding motor/drive and by size and year
https://www.mercruiserparts.com/mercury-marine-parts-lookup-drawings
The link shows
Alpha 18643A5...
Get a short piece (4 to 8 inch) of clear hose from the hardware store and a double barbed fitting and hose clamp. Disconnect the hose at the thermostat coming from the drive and put hose in between. See if you see bubbles with motor running
Use the dipstick
Many motors do not have a dipstick tube which goes down far enough to get most the oil out. Would have to use smaller plastic tube down dipstick tube so it reaches further. Either that or use drain pan plug and remove it
180 to 200 is way to high. To be that high the gauge is not accurate
If the test was done cold and not warmed up, this will cause issues also.
Unless the "Mechanic" (so he's called) also did a leak down test I would ask just how does he know the possible issue is the head, the rings or just a...
If #6 is the lowest I wouldn't worry much about it. While 150 is new motor, 120 for a cold motor is not something to be concerned about right now.
What caused you to run a compression test?
A carb has a fuel bowl
The pump fills the fuel bowl
If the bowl is filled prior to cranking the motor it should start and run until the carb bowl goes dry (5 minutes or so at least)
Want to find out is it the carb or something else
I understand pump does not run when plugged in, but it does "run" when you jump it, Right???
So jump it and let it run for 30 seconds.
Reconnect correctly to the motor and see if it will now start?
If you jump the fuel pump with the line connected to the carb for 30 seconds, the carb will be full and the motor should start
Does it start if you jump the pump for 30 seconds and then try to start?
