So i bought the gauge with the gauge kit and am getting ready to hook it up, Do i need to use the pressure gauge isolator shown in the pics? and if so what does it do? also i have a schrader valve coming off of my vp44 can i plumb the gauge in there?

I'm leaning towards the 1/8" line being the culprit too. Its very difficult to get all (if any) air out if that size line. Did you also remember to make sure the isolators diaphragm is properly positioned? You take the eraser side of a pencil and gently poke it in the gauge line side to make sure the diaphragm is pointing fully towards the fuel line side.

I went through this a few months ago. I put a schrader tee right up into the isolator so I could purge air out of the fuel line right up the the isolator. I pushed the diaphragm in with a pencil eraser end, then filled up the gauge end with 50/50 mixture of anti freeze. Then took a plastic pop bottle and drilled a small hole in the cap. Filled with anti freeze mixture and stuck the 1/8" tube into the cap at the gauge. Once I could see no more bubbles coming out of the clear line under the hood, stick it into the isolator fitting. My intent was to purge all air from the isolator to guage. I got push fittings for both ends instead of the olive compression fittings. Much easier and re useable.

I'm leaning towards the 1/8" line being the culprit too. Its very difficult to get all (if any) air out if that size line. Did you also remember to make sure the isolators diaphragm is properly positioned? You take the eraser side of a pencil and gently poke it in the gauge line side to make sure the diaphragm is pointing fully towards the fuel line side.

yep....i set the diaphram before i filled it w/ fluid

oh, well... im gonna give the 1/4 line a try and if its a "no go" , im gonna ditch the isolator....

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finally got-er-done...LOL

Def use 1/4 line from isolator to gauge..thanks everyone for the tips and suggestions!!!!!!!

Glad it worked for you.