beer foaming and spitting

my homemade draft system foams and spits on first pull of tap,but settles after 3-4 seconds, then it pours perfect,then after sitting for maybe 10 minutes it does the hole thing again. i have replaced beer lines ,facet,shank, beer keg is in basement,in fridge,temp. reads 30deg. line runs are,10feet 5/16,4feet 3/16 and rise is 7-9foot,all line is insulated with 1/2 inch pipe insulation

any help will be wellcome

Just insulation on the lines isn't going to cut it. They need to be cooled.

Yep, you need to run a cooling line alongside the beer lines. You can try to DIY it or check out these. If you want to be sure that the cooling is the issue, you could always hook up a picnic faucet inside the fridge/freezer and see if it still foams.

thanks ,did not know if i needed to cool lines or not,i will be trying a diy cooling system

If its 'spitting', then you probably have a problem with air in your lines. Check them to see if there are any bubbles. The most likely scenario is that your lines go up vertically and then back down, creating spots for the co2 gas to 'pool up' at the top of the lines. It's a good idea to be careful that the lines only go up or horizontal (coiled, for instance) after leaving the keg. Another possibility for co2 getting in your lines is that you are not maintaining the proper pressure inside the lines. If you are turning off your co2 (and have a small leak), a decrease in pressure in the keg could cause the beer to flow back into the keg, putting co2 in the line.

EDIT: Just re-read your post and see that you have a 7-9 foot vertical rise. I think your problem is definitely that the amount of pressure in the keg is not enough to 'hold' the beer in the lines. Is there any way to put in a one-way check valve to prevent the beer from dropping back down? I use sankey's and the couplers come with check valves built in. The other option is to increase the psi of course, but you might have issues of overcarbing if you go too high.

Sounds like there is a leak in the air system where it is not keeping pressure on the line and allowing the beer to run back into the keg. This causes those first few seconds to be spitting foam