low vacuume test results for fuel pump

[Bary0802]

I have a 76 merc 650 that has fuel starvation I did a vaccume test and only got to about 1.5in which is below standered of about 2.5in. but was able to Idle fine and run in low throttle but as soon as I put it in High throttle it dies. the thing is is that I have replaced the fuel pump daiphram 2 times now it keeps tearing and am not sure why? any insight on this issue?

 

[latin monkey]

Re: low vacuume test results for fuel pump

have you replaced the check valves in the fuel pump?

 

[Bary0802]

Re: low vacuume test results for fuel pump

no I havn't I am not to familiar with replacing those just replacing the diaphram but the thing is is that when I prime the bulb when its running it doesnt effect the RPM like it used to before I changed the diaphram, how do you replace them if needed?