12 volt vacuum pump amp draw question

[22dog22]

i have this 12 volt vacuum pump hooked up, the directions state to use a 10 am fuse, if I hook up the pump to the brake booster it blows a 10 fuse, if I do not hook the vacuum hose to the booster it does not blow the 10 amp fuse, it seems when I put a load on the pump it blows the fuse could it be under fused ? [ need higher amp fuse] when I go on the internet I see other vacuum pumps that look like mine and they say to use a 20-30 amp fuse what are your thoughts ?? not sure how to measure the amp draw when the pump is under the load

 

[KitCarlson]

There are clamp on DC amp meters. Here is an inexpensive one.dc amp meter - Google Search

 

[67Dart273]

I'm with Kit/ Dave but if the instructions are clear and there is nothing else on the 10A fuse, I'd suspect the pump is bad

 

[KitCarlson]

Measure the voltage too, if the voltage is low, the current increases.