Well that's the plan today, So much for my thinking it would help cool better. I have a stock pump in the shop that I'm gonna put on right after I finish my morning gallon of coffee.
I have Vortec with a heater and I had a lot of air pockets that were hard to get rid of but the biggest thing I did that helped was plumb one of the heater hoses thru the p*** side cyl head between #6 & #8. Take out pipe plug and insert a 90 degree elbow pointing rearward. It also made for cleaner routing of the heater hoses and help flow which reduced temp.
Ok, not to take this thread off the rails, but once again we have people giving advice who don't really grasp the concept of how the cooling system functions. The following isn't my opinion, it's just simple logic... What are we really trying to keep cool, the water? NO, we're trying to keep the metal parts of the engine cool. The water is simply the medium which transfers heat from that metal into the radiator (heat exchanger) and then to the ambient air. What the high performance water pump is supposed to do is build block pressure, which shoves the water more tightly against the walls of the coolant p***ages and allows the water to pick up more heat. Think about this simple experiment (please dont TRY it...): Turn a burner on your stove to high...this is heat from the combustion process. Now swipe your hand (the coolant) quickly across the burner...if you go fast enough, you wont get burned because you didnt have enough time to transfer any heat from the burner to your hand. Now, if you press your hand down on the burner, you will burn the hell out of yourself because your hand (coolant again) had more time to transfer heat from the burner. The water pump and thermostat work in exactly the same way. If the water flows too fast, the water temp (gauge reading) stays low because there simply not enough time to get the heat out of the metal parts of the engine. This is NOT a good thing. More flow is not the answer.
In a pressurized cooling system, you already have pressure to push the water against the metal parts. If the performance water pump increases the block pressure, that pressure builds up against the thermostat. A normal thermostat would have to push against that pressure to open as the center moves inwards against the flow direction. It could require the thermostat to get much hotter before it can open against that pressure. That might be where a thermostat designed to work with the pump might come into play. A delay on opening could make temperatures climb. The only reason I can come up with for making a high performance water pump would be to prevent cavitation at high rpm but that can be accomplished by using underdrive pulleys.
When you add your water or coolant make sure that your heater is on (low). All of the sounds like you have air pockets. When the stat opens and there is an air pocket the sender reads the steam temp. Start the car with out the cap on and let it cycle the stat that usually helps with the air pockets. Maybe try raising the front of the car so the air goes to the top of the radiator.
Do you have a way of confirming that the engine is actually heating up and cooling back down? I have an infrared thermometer that allows you to check real time with your gauge. It might be a gauge issue.
Not exactly true... Yes the entire system is pressurized to some extent, but this is more to raise the boiling point of the coolant to prevent loss. The pressure in the radiator should always be somewhat lower than the pressure in the engine itself. If that weren't the case, why would we need an outlet restrictor (or thermostat, which acts as a restriction as well)? The design of a good high performance water pump should allow it to build more head pressure. That's why they close off the back of the impeller, where most OEM pumps don't bother.
All it takes is for someone to have a bit of a problem and all the off the wall theories come out about how to fix the issue. You are correct in that the radiator cap's pressure level is what builds pressure in the system and that the pressure is to raise the boiling point. I haven't read something such as a water pump raising the pressure inside the block since one of my former students use to come in with his off the wall concept of the week 25 years ago. Engineman, your first name isn't Bucky is it? I'm inclined to agree with those who think that the high performance pump is pushing the coolant though the engine too fast to properly absorb the heat from the block and heads and dissipate it though the radiator. I would check the radiator fins for bugs and other foreign matter that may be clogging it though. I've got an ot van out by my garage that the p/o burned up the engine on because the radiator was clogged on the outside with dirt that had ac***ulated on the fins on the trans fluid that had leaked out of the trans cooler hose.
Well guys thanks for the input, Chuck up another one up for the HAMB and it's great knowledge. The standard water pump is on and temps are right at about 180/190 which is better than the last WP I had on it before. It's also not a total loss the high flow is going to a circle track friend of mine for his car.
You got the wrong guy with the water pump pressure. That was exwestracer's claim. I just pointed out that if the water pump does increase the pressure, the thermostat has to open against that pressure. The thermostat wasn't designed as a restriction but to warm the engine up faster and keep the minimum engine temperature up. To fit it in the engine, the port it sits in needs to be rather large. If you remove it, the flow will increase but it doesn't seem to be a problem at normal highway speeds and loads. At high engine revs the pump seems to need a restriction. I ***ume it is to allow more time for the coolant to pick up heat in the engine and dissipate it in the radiator which is why I doubt the need for a high flow water pump I don't think that the water pump could increase the engine pressure very much or the heater core would blow. In this thread, the problem started with a water pump change. The car didn't overheat before the pump change. It seems a valid ***umption that the new pump is the problem.
Glad you solved your problem and I think you knew it was the pump and are giving everybody else credit. Sometimes we just need somebody else to confirm our thoughts.
So what is going on with these pumps? Increasing the rate of water flow through some engines can adversely effect water flow patterns. Older engines often had an individual water pump for each bank of cylinders. That was done because a single pump tended not to evenly and consistently move the same amount of water through each bank. Modern pumps pretty much cured that. Possible there is something about the design of these pumps that results in inconsistent flow between cylinder banks? Higher flow capability doesn't necessarily mean higher pressure, but I do know of cases where a balanced(Robertshaw type) t-stat was needed for proper temperature regulation.
Actually I was hoping it wasn't but for the most part your right. My mistake is I didn't research it .
--------------------Quoted from last week--------------------------- 355 sbc thats been together since '04 and always ran at 160 deg. Last yr I had to replace the water pump (casting around tapped hole broke off), A coworker gave me a brand new take off from his crate engine (***uming its not reverse flow). I ran it a couple times after that and it stayed around 180-190. I could deal w/ that and figured it was just not as efficient as the previous pump. Fast forward to last week. I finally got the car out for the first time this year and now the water temp is going crazy. 2 miles down the rd and the needle starts climbing. I saw 270, the wife says it was higher. Slip into neutral and bring the R's up and itll drop to 190. Back in gear and just rolling along and up it goes again. Do this a couple times and It will finally settle down to 170 and be fine for the rest of the ride (no matter the speed). Ive pulled the the thermastat and confirmed its working. Ive left the cap off the rad and confirmed the coolants flowing (The same exact temp fluctuations occur while doing this in the garage and not driving). I have noticed the top rad hose and the drivers side rad tank do get hot and the core and p*** side tank stay cool for most of the time. Looking down the rads opening and bringing up the idle (aprox 2000rpm)will cause the coolant level to drop in the p*** side tank and then the coolant starts flowing in from the core, this will finally heat up the p*** side tank and lower hose. Sorry that was long but I wanted give as much background as possible. Any help ? ------------------------------------------------------------------------------------------Quoted from last week------------------------------ Wow, its like we were on the same mission there. Looks like I should just bite the bullet and replace my pump. Still dont quite get this place, my post gets two replies than disapears to page #150, and others get tons of help, huh? jeff
Been there done that it's just how it goes sometimes don't let it get to ya. BTW being a crate engine it's possible it is a reverse flow. My issue was a high flow pump, Similar type problem different pump probably.
Sometimes it depends on who's online. Topics move down the pages so fast that we don't all see every post. We try to help when we can and if we see it. If I see a topic that I don't have an answer to, I might make a suggestion just to bring it back to the front page where someone else might notice. You can bring the topic back up yourself by telling us things you've tried to cure it. I think we've all learned that, when it comes to water pumps, stock isn't a bad thing. Automakers do a lot of engineering and testing to make sure things work. Others come up with ideas but don't do the testing so you do it for them.
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