Hey guys. After cooling issues with my H22, I decided to go with an electric water pump setup, I am using a PRP 50gpm billet pump that is inline between the outlets on a custom rear water pipe, and it is constant to prevent hot spots. I had issues with the overflow tank overflowing, so I removed the thermostat which had 8 1/4" holes drilled in it to see if that would cure the issue, but it is still overflowing, and I have a standard 16psi rad cap, so I am wondering if there is a secret I am missing? I am sure I could make the cap constantly closed, but I would be worried about the coolant not having a way to evacuate, so if anyone has some insight please share, thanks.

 

Do you have the water pump flowing the correct way?

We had issues with a K series car pushing water into the overflow constantly. Turns put the water pump was pulling from the block and pushing into the radiator causing it to push into the overflow. We flipped it around and problem solved.

Granted, this is a different scenario, just an idea.

 

I am actually not sure in this one, you would think on the pump it would show the direction of flow, but it didn't so with my luck it is backwards.

 

I emailed PRP to ask them why it is so hard to make a product and not put any kind of marking for the flow direction, nothing was even said in the "instructions". Im gonna be pissed if I have to pull my damn IM off again to work on it.

 

Do you still have the fins on the belt driven water pump? The electric water pump could definitely be a problem if you're trying to flow water in the opposite direction with the electric pump.

That being said, is it getting hot after a pass or just flowing into the overflow right away?

50 GPM is a lot and is definitely not necessary. Most of the electric water pumps only flow that amount with minimal restriction. Flow is significantly reduced by a pressure causing restriction (such as the headgasket and or the radiator).

If the cap overflows as soon as the water pump is turned on or before the temp is to boiling, then I would look into the flow direction of the water pump or look for a restriction in the radiator. If the cap overflows because it gets up to temp and beyond quickly, then I would again look into flow direction of the pump and I would also make sure that the engine doesn't have a headgasket problem by running the engine briefly without the water pump on (while monitoring the temp) and watching if the cap overflows before it reaches boiling temp.

You obviously need to have a radiator cap to allow for the natural expansion of the coolant with heat. I hope that helps!

Bottom line, check the flow direction

 

Yeah, could be too much pump or you have problems elsewhere with headgasket issues. Ive been running a Mezeir Electric water pump on my SR20 for over a year now and I love it. Car stays very very cool. If your cooling system is overpressurizing you got one of two problems, either your flow direction is wrong and your normal water pump is still in function or you have headgasket problems.

The only time the the hose should harden is after it heats up. The pump really wont cause that unless there is a restriction. And even then it shouldnt heat up enough to open the cap unless its overheating or your cooling system is getting pressurized due to exhaust gasses.

If you said you were having cooling issues before the electric water pump then my guess is on headgasket issue.

 

Okay so according to PRP the pump is installed correctly...so can you guys specify more on the issue of the headgasket. It is a fresh motor with 300 miles on it with a new oem MLS gasket, and the car drives amazing with no visible issues with the HG.

 

Overheating and pressurizing of the cooling system is a pretty big sign of headgasket issues. Something isnt right. Like i said if you were having issues with the stock stuff, your problem isnt the electric pump. Again im running one and my system pressure stays well within normal. Actually the hoses remain pretty soft because the car simply runs way cooler. Highest temp i saw after doing multiple runs on the dyno was 181 deg. Im running a dual core civic radiator, Mezier electric water pump and blockoff plate and a Flexalite 1250 cfm fan on all the time, no t-stat. Most of the time the car runs at about 160-170deg driving around, stop and go, doesnt matter. Even during 120 deg summer days i could blow through the gears at 20psi of boost during the middle of the day and my temp would stay below 180 deg. I love it.

Something is up.

 

Well I guess I should have been more specific when I said cooling issues. After researching, I guess it wasn't THAT hot, but too hot for me. My stock needle would be where it was from the factory, but I would see hot cruising temps of 200-210 on hondata, and it seems as similar built cars to what I have also run that hot with the stock pump, I just wanted to be closer in the 180's, hence why I went electrical. I am going to try and see if I can get a higher psi cap to fit my rad tomorrow and see if maybe a 20psi will keep it in there.

 

Need more details.

-What radiator?
-Still have the oem pump?
-How long does it take to warm up?
-How fast does it overflow? is it instead?
-Does it have the bypass hoses on the back?
-How much stuff is blocking the radiator?

 

2001 Prelude

-What radiator?
Mishimoto Civic Dual Core

-Still have the oem pump?
It is on the motor, but fins are clipped and used as an idler

-How long does it take to warm up?
At least 10-15 from a cold start

-How fast does it overflow? is it instead?
It will overflow very soon, within a few minutes of idle time

-Does it have the bypass hoses on the back?
yes the bypass hoses on the water pipe are still there, and the heater hoses are looped in the rear.

-How much stuff is blocking the radiator?
24x3x12" Intercooler, intercooler shroud to direct air through the core, 10" fan on the back of the intercooler to pull air to the rad, and a 12" puller on the rad pulling air through. Stock bumper opening.

 

So PRP told you it was installed correctly?
Not trying to be a jerk, but have you verified that it is flowing the same way as an oem pump would ?

 

Well I assume that the timing belt side of the motor where the water pump is, I would think that the flow direction would flow OUT of the rear of the water pump into the water tube, sorry if that is a horrible description, but if that is the correct way the water flows, then I have it correctly set up with the elec pump.

 

Glade, I honestly wonder if your pump is just too much flow for the restrictions of the block, head gasket, radiator, etc, and building too much pressure? Stock cap holds somewhere around 16-17psi, right? maybe 50gph is just too much?

Also, Im pretty sure the OEM water pump PULLS water, not pushes. The bottom hose is a feed, and the top hose is a return to the radiator. So if the bottom hose is connected to the t-stat, and the t-stat is connected to the water pipe, the water pump is pulling to make that hose a feed.

So maybe it IS backwards?

 

Hey Curtis. Im glad you brought up the direction, because after looking at pics on google, I think you are right and the pump actually does pull the water and not push it just judging by the fin directions. If I get some time tomorrow I will flip the pump and see what happens.

 

Take a look at the way the pump is flowing into the radiator. Based upon the way they told you it flows, is it pulling from or pushing into the radiator.

It could be just a simple placement issue that it needs to be farther from the radiator.

I believe OEM radiator caps are 11-13psi. Most of us use a Meziere water pump that pumps 20GPM. I data log coolant pressure . I usually see 6-8psi with a few spikes higher then that. I have yet to see higher then 11psi. I use a 13psi cap.

I could see 55GPM being a little too much for your system, espicially if its close to the radiator.

 

Electric Water pump should be setup to pull water from the bottom of the radiator and push into the block. allowing the hottest water from the head to be pulled into the top of the radiator.

 

Correct! If you have it mounted on the water pipe it should flow from the t-stat housing to the block. It sounds like you have it in backwards. Also, if there's no t-stat then delete the bypass hoses.

 

Nice, deffinatley sounds it's backwards then, so I might throw the thermo back in since I am flipping it and see where the temps sit, and take it out if it's too cold. Thanks for al the help guys.

 

Well I got the pumped flipped and the thermo in and no overflow, and full warm up never went over 182, so I am gonna take it for a drive and see what she does.

 

well, just got back from a short drive, and it was still too hot, hit about 212 cruising, so I am going to let it cool enough to where I can pull the thermo and see what that does, otherwise I obviously have a headgasket issue.

 

well pulled the thermo, and same issue, I have fully heated the motor, bled the air, and same thing within mins of driving temp gradualy increases, this time hit 206, so there is obviously another issue, was hoping to not have to pull the head but I dont know what else to do, I just dont see how anything could happen to the brand new hg especially at 8psi, but I guess there is only one way to find out.

 

you need to get rid of the bypass hoses. there just letting hot water recirulate through the head and not reach the radiator to be cooled. had the same issue with our shop car. deleted the bypass hoses and temps went from 205 down to 180 .

 

If the pump is too strong, it could be pushing the water too fast not letting it cool as well.

At this point it might be wise to just pull the head and see what it looks like.

 

are you talking about the two hoses that are on the rear water pipe?