Thread: Need Help: Meziere water pump flow direction

Well to start off I basically drove 2 hours away to get my new build dyno tuned, and ended up leaving after being stuck on cooling issues for several hours. I was on the phone with Meziere (who by the way have awesome customer service) and they mentioned how the flow of the water pump should inlet side bottom of the radiator and feeding towards the thermostat housing. From my understanding I thought the conventional flow for the sr20 is from the back of the cylinder head and out through the thermostat housing, so that's how I currently have the electric water pump oriented. Can someone confirm that I have my pump flowing in the right direction.

Very unfortunate, however we just couldn't get the car to burp. I opened up the bleeder port on the pump and water gushed out. I took off the bleeder screw on the thermostat housing, and even left it open with the car running. It would spit out water every now and then, but just wouldn't get a steady flow coming out. I have a funnel attached to a special radiator cap on the radiator so a constant supply of water and a place for the air bubbles to escape to is there as well. Water pump is pushing water, it's just not getting a good flow passed the block. Would love to hear anyones feedback and suggestions so i can resolve this issue. If so i can attempt to go back thursday and hopefully make it out to streets of willow friday

Brian

If you're still running a thermostat your symptoms sounds like it may have kicked the bucket.

compression checked fine, no oil/coolant contamination, no smoke out the tailpipe, idles and revs fine even under load. we took off the thermostat during the troubleshooting process. when i said water gushed out, i was implying there was no air in the system, or cavitation in the water pump.

I think you got it backwards. Coolant should be flowing from radiator > thermostat > back of cylinder head.

On the Meziere pump there is an arrow to show you the direction of the flow.

If you are going to race, take out the thermostat.

Good luck, Brian.

Edit: You're right.

See above.

I've never had the issue with getting air of the system as you describe. I was at a buddy's shop when he was filling an SR with coolant with a funnel as you describe and saw it take a good hour or so to get all of the air out of the system. It was a weird thing. However, after a long enough time it did get sorted. What seemed to be happening was that there was an air bubble by the thermostat bleed that would just not go away. It finally all sorted itself out once we turned off the car and let it cool. It really sucked in the coolant then, and pushed out the air. Spend a lot of time and you'll get it done.

NO, you got get wrong.

Go to page 17, it will show the coolant circuit. http://www.nicoclub.com/FSM/Sentra/1996/LC.pdf


If anything I miss labeled the coolant hard line and called it "back of the head" because that what Brian called it. I use the same name to help him understand.

It should be radiator > thermostat > hard coolant line/back of the block > water pump.

thanks for the response guys! good ol' FSM, i should have looked there as well. thanks Robert, i'll flip it around ASAP!!

On the drive home from work today it crept into my head that I might have had it wrong. I checked the FSM and saw that I was wrong. I came here to correct things. Sorry for the bad info.

A handy tool to have/make: get a spare radiator cap and add something under the diaphragm to keep it open (I bent a small nail). To burp, simply put the modified cap on and make sure the overflow tank is full. Get car up to normal operating temp as you normally would then just turn the car off and let it sit. It'll eventually suck the coolant right out of the overflow tank so make sure it doesn't go dry. Rinse and repeat.

I was talking about the thermostat not your motor I hope you get things figured out and get it tuned.