Bosch A2W pump issues?
Thread Starter
Staging Lane
Joined: Mar 2018
Posts: 70
Likes: 0
From: Manitoba
Bosch A2W pump issues? Just got a new Bosch A2W intercooler pump for a new build. Set it up to check/confirm flow and absolutely nothing... Pump is running but no water. Pouring water directly into the inlet and nothing... Any suggestions? Thought I'd find something searching but came up dry... 
Are you literally pouring the liquid into the pump suction? Try providing a small suction bottle so the pump can’t suck in air and cavitate.
Are you sure its wired correct and not spinning backwards? Those Bosch pumps are usually pretty reliable.
Are you sure its wired correct and not spinning backwards? Those Bosch pumps are usually pretty reliable.
Thread Starter
Staging Lane
Joined: Mar 2018
Posts: 70
Likes: 0
From: Manitoba
Well I've got 3 choices for cooling. 2 different heat exchanger/coolers vs ice box. So I set up a test in the sink to see how much flow I was going to get out of the one cooler. I put a 12" suction line on the center inlet port and nothing on the outlet to start. Red + Black - and nothing. So I poured water right into the inlet to make sure it was primed and it still didn't exactly flow right. Then back into the water with and without the 12" suction hose. I saw youtube videos of guys running them that way in the tub with a longer suction line and they sprayed fine.
I haven’t watched any YouTube videos on these pumps but I don’t think they like to pull suction up. IME they’ll work best when the pump is mounted below the surge tank/ice box water level. This allows gravity to help feed water to the suction line and keep them primed. And they don’t exactly flow a ton as it is. Is this the ctsv style Bosch?
They should be at a low point In the system and gravity fed water. Top is inlet and side is outlet. Also the Bosch pumps are poo and don’t flow well compared to other options. People like them bc they are cheap and last a bit (abet they are brushed pumps) but eventually wear out and might last a year or two depending on run time.
Personally ive run a few pumps and the best ones are the peirburg brushless pumps, they are beasts and ford even upgraded to them on the new cobras for 13-14 I believe. Price isn’t that bad considering they will outlast lots of replacement boschs. The peirburg CWA-50 is the smallest and they blow the Bosch out of the water. Also Davis Craig has one that’s brushless and I’ve used it and it works better than the Bosch and should hold up for a long time.
Personally ive run a few pumps and the best ones are the peirburg brushless pumps, they are beasts and ford even upgraded to them on the new cobras for 13-14 I believe. Price isn’t that bad considering they will outlast lots of replacement boschs. The peirburg CWA-50 is the smallest and they blow the Bosch out of the water. Also Davis Craig has one that’s brushless and I’ve used it and it works better than the Bosch and should hold up for a long time.
Thread Starter
Staging Lane
Joined: Mar 2018
Posts: 70
Likes: 0
From: Manitoba
Ok that’s great info, thanks. You were right, I had to set up a different way to feed it to test the heat exchanger. Pump does work. The smal heat exchanger will not, too much restriction. 1 option eliminated anyway. I will keep those pumps in mind.
thanks
thanks
