what size water lines

[jstwkd]

What size water line with steal braided system should I be running?I'm curently running - 6.Is this to small?502 BBC thermostate housing.two exits

[Cheyenne19]

I am running 8 but I am going to reduce my exit inorder to force more water into my headers.

[HBjet]

-6 from the pump to the block it too small. I would at least run a -8. On my boat. I run -10 from the pump to the block which pumps through 1/2 inch openings. Exiting, I run -12 from the manifold to outside the boat, and -6 from the manifold to the headers.
Good Luck!
HBjet

[HBjet]

Originally posted by Cheyenne19:
I am running 8 but I am going to reduce my exit inorder to force more water into my headers.
Don't do that. If you want more water in your headers (which is another question in it's self) Remove the water jets from the headers and drill them out a little larger. Much cheaper.
Now, why do you want more water to your headers?
HBjet

[78Eliminator]

Question: What if you never run water through your wet headers?
There are two reasons for wet header, right?
1. Reduce exhaust decibles
2. Cool motor
So if your motor is running cool, and the cops are not around to bust you for noise, dry is fine, right?

[jstwkd]

I run -6 from a pick up on the bottom of the boat for the headers.The rest of the system is also -6 and I'm running the 4 hole thermostate system.Wich I found out actually btpasses motor at high rpms.So this may be part of my problem.But the temp. gauge flucuates 160- 180.I'm trying to figure out why I heated up one side of the block and killed 2 intakes and three pistons.

[JEThro]

Travis,If I were you,I'd go back to the basic plumbing setup to start with and then start modifying it in steps. I don't know much about running a thermostat so this might be a stupid question. What circulates the water when the thermostat is closed? Also,are your headers only getting water from the pick-up on the bottem? I think you would be taking a chance of flooding them if you went from high speeds to no speeds. Jethro
P.S. Is that offer still good on those parts?

[Cheyenne19]

HB,
one side of my headers is not getting water to it. The T valve works fine, the problem is that the water flows in the path of least resistance, which is out the water line through the transom. So I am putting a cap on the end of the lines and drilling a hole in the cap in order to reduce the size of the line, this will build up more pressure and get more water to my headers in order to prevent blueing it. It will also raise my temp. to over the 135-140 range that it now runs. But you are right i could drill out the holes to the header, but isn't the actual water line to the headers still very small?
c19

[Oldsquirt]

Cheyenne, it's fairly common to just install a valve on the water outlet hose. This allows easy adjustment.
Sounds like you may have some blockage in the hose from "T-valve" to water injection manifold, or in the water manifold itself.
You might want to do some reading at Bassett FAQ (http://www.bassettracing.com/newpage7.htm).

[jstwkd]

Ok call me an idiot.I talk to the guy who set me up with my plumbing and I'm running -8 .will this be ok?

[LVjetboy]

Jstwkd,
I think -8 inlet is fine. In fact, I used a -8 inlet restricted by valve to probably less than an equivalent -6 with no problems.
Lot's of variables here. Your hp output will determine how much cooling (flow) you need. Your pump condition (clearances) as well as impeller size and rpm will drive bowl pressure and coolant flow rate for a given line size. Since not everyone's engine and jets are the same, you'll see different opinions.
But I think for most of use mild engine guys, a -8 is plenty. Your mention of a 4-hole thermostat running 160 to 180 sounds similar to a rex tower, but not much info to go on? If your thermostat is similar to rex design (likely), then bypass is temperature controlled and not rpm controlled.
Killing two intakes and three pistons can be a temperature thing, but here again there's lot's of failure modes so consider other possibilities before deciding line size is the solution. A build-up of sand in the block, for example, may overheat one bank and cause failure no matter what the line size.
Cheyenne19,
Header flow balance is an issue as you've posted. Even with equal lengths and hose size, small variations, corrosion or blockage can upset the balance and make one header hog the flow. A simple solution is a small flow valve on each header line. Not only balances flow and gives total flow control, but also can "clear" a plugged line by shuting the opposite side temporarily.
Although Bassett shows an exit valve and lists a proceedure to force more flow to the headers by restricting a dump line, I think this has risk. Maybe common as Oldsquirt mentioned, but not necessarily the best solution.
If you check my cooling diagram, I place that valve before the engine, after the t to the headers, so I can still "pressure" the headers if needed by restricting flow before and not after the engine. This way no danger of overpressuring the engine while attempting to adjust header flow... a much safer solution I think. The only risk being restricting engine flow too much. But if you watch your temp gage while adjusting, no worries. Also, you'll flood your headers long before you reduce engine flow too much.
JeThro,
On the t-rex, some circulation is allowed by a hole in the housing even when the thermostat is fully closed. There is no pickup on the bottom, just flow from a high pressure tap off the pump. So when you lift throttle suddenly, the tap pressure drops very quickly too.
78Elim,
There's a couple more reasons...
3) Keep the chrome on
4) Keep them cool
#3 although not important to those who's chrome is long burnt...very important for those who's chrome is shiney.
And #4, keeping them cool is nice if you or your honey bump against them...in fact, the original reason for water injection I believe...to keep the pipes cool.
jer

[Heatseeker]

LV,
I've seen your cooling diagram. I think it is well thought out. I am going to use the seperate flow controls to the headers at some point. For now I have a single ball valve, and it seems to work fine.
I am planning to put a pressure relief valve on the exit line(the p.r. valve has a seperate overboard, also). This was suggested to me by a guy who's been running it on a BBC Tahiti for at least 15 years. This make sense to me for the following 2 reasons:
1. It keeps the block full. If I restrict the inlet flow, couldn't it cause air pockets in the jackets?
2. This will assure me a constant block pressure. I should have no over-pressure problems.
I'd like to hear your thoughts on this one. You must have already thought about this yourself. Why did you go the way you did?
John
Oh yea, I bumped my leg on my wet pipes one time. I still have the tattoo to prove it http://www.planetsmilies.com/smilies/sad/sad15.gif !
[This message has been edited by Heatseeker (edited June 20, 2002).]

[froggystyle]

Not that it applies totally to you guys, but I just re-engineered the cooling system in my boat.
Problem... I was running good temp at idle, and at WOT for a period I would heat up my oil and have no water temp whatsoever.
Reason... Little known fact that too much water actually reduces the ability of the water to cool the engine. It has to stay in the block for a while and heat up in order to transfer heat. Plus, the higher pressures generated by the pump will cause havoc with the head gaskets eventually, as well as every other water seal on the boat.
Solution... I bought a pressure reducing valve at Home Depot for $30 and plumbed it inline from my pump outlet. With a gauge port in front and a gauge port behind it, I can regulate the pressure and monitor where it is set at. Currently, my pump produces well over 150 lbs at WOT, and I am reducing it down to 15 (The pressure of an automotive system)
The next step was to order some Moroso restriction washers for my thermostat housing. In a race car I used to run, we could never get the thing to warm up (same theory) so we put these washers in place instead of a thermostat. Works great. I used the Gold version (smallest hole) and now have much better cooling and warmer water temp at all RPMs. In addition, it provides some restriction as the water leaves the block, keeping it in there a little longer.
I could never run a thermostat in my rig as it is plumbed, because my water-jacketed and powdercoated headers would melt immediately (they need constant water) and my entire engine water exits through my headers (unlike OT headers) so valves were out.
Total cost of modifications...
Valve $30 Home Depot
Fittings $13 Home Depot
Restrictor $8 Summit Racing
Gauge and hose $20 Controlled Motion
(I can plug and unplug my ports and install the gauge in either my intake piece, before the regulator or after the regulator)
This will be the first hard weekend on it, but it appears fine. I will update you all later.

[HBjet]

Hmmm, wasn't this all covered in the Gate Valve thread?
Froggy and Heatsinker, Good Job!
LV, you crack me up.... http://free.***boat.net/ubb/smile.gif

[jimsride]

HEATSEEKER IS TALKING ABOUT A PRESSURE RELIEF VALVE ON THE OUTLET LINE. WHAT TYPE OF VALVE AND WHAT PRESSURE SHOULD IT BE, WHERE DID YOU GET IT. LV, WHERE IS YOU'RE COOLING DIAGRAM POSTED? I WOULD LIKE TO CHECK IT OUT.

[LVjetboy]

Heatseeker,
A pressure relief can work just fine, but my concern is the regulator eventually sticking from dirt and corrosion. Especially if you regulate the dump line. RioDog had a good suggestion in the gate valve thread, he put a regulator on a tee to a dump excess inlet pressure before the block. That way if it got stuck open or closed, less likely to damage engine.
I don't run a pressure regulator because my engine doesn't have the hp to overpressure the block at full throttle (with my cooling setup). So in my situation, a simple valve system works well.
You have a good point about water pressure and hot spots. An extra 10 psi will raise the boiling point of water about 20 degrees...all good things. My exit pressure is probably on the light side (5-10 psi) but I can adjust up if needed.
So on to your comment about keeping the block full by regulating exit versus inlet flow.
Just for discussion, say there's a 10 psi pressure drop across the engine from inlet to outlet at full throttle flow rates. I haven't measured pressure drops yet (only exit pressure)...but just for example. Then if you set an inlet pressure regulator to 25 psi, you'd get nearly the same effect as setting an exit pressure regulator to 15 psi...ignoring a slight difference in flow rates of course.
So the average block coolant pressure in each case (and hot spot protection) can be similar for either inlet or exit regulated systems if you set the regulation pressure to account for block pressure drop. And an inlet regulated system is less prone to damage from failure, so would be my first choice if I ran a regulator. I'd avoid any restrictions on exit or dump lines.
Froggy,
That thing about too much water, or water flowing too fast, or needing to stay in the block (or radiator) longer to pick up heat is actually an urban myth. Fast-flowing cool water only improves temperature delta and boundary layer mixing...all good for heat transfer...unless it flows so fast it separates from the internal passage walls. Not likely with flow rates we run.
The real reason a thermostat or restriction improves internal heat transfer is by increasing coolant pressure, which ups boiling point temperature...reducing steam pockets and hot spots. If I remember you have big hp (compared to me), and an oil cooler may be more effective in controlling your oil temp at full throttle than increasing block coolant pressure.
Jimsride,
Here's one from my website:
http://users.lvcm.com/lvjetboy/CoolantDiagram.gif
Not saying this is the perfect system of course, that goal is always just around the corner http://free.***boat.net/ubb/smile.gif
HBjet, glad I could humor you.
jer

[froggystyle]

Your input is greatly appreciated, and I now need to find out why this worked. Bottom line was... at WOT, for a long period my oil temp would get upwards of 280 degrees... I know, I know... Time to change the oil. Now, the oil temp will not raise above 190, the water temp is nearly the same (up from 120 ish) and all of the planets are aligned.
Urban myth or not, this practice has gotten two separate high performance cooling systems of mine (alcohol Dirt-Modified and the jet boat) to operate properly, and both were ineffective without the exit restrictor keeping some water in the block longer.
At WOT, I could watch my water temp go down and my oil temp go up. Now they both go up together, and come down together. Worked for me. Not to mention that this regulator does not have a pop-off discharge, and as minute as it may seem to some, if pressurized water is going out the back through an overboard discharge... it is not creating thrust going out the jet.
That is a phenomenal diagram you showed by the way. I will reference that time and again regarding cooling for others.
On that note, an oil cooler is probably next. http://free.***boat.net/ubb/wink.gif

[LVjetboy]

Hi Froggy,
I didn't mean to say the t-stat restrictor is an urban myth, just that the reason it works is by increasing pressure instead of because of a slower flow rate. The myth part is about the water needing to spend more time in the block in order to pick up heat.
Thanks for posting your experience with water and oil temp. The whole issue of water pressure effect on hot spots, and ideal block pressure is interesting to me.
jer

[jimsride]

LV- CHECKED OUT YOUR DIAGRAM, WHAT CONTROLS THE FLOW THROUGH THE BALL VALVES? DO YOU PLUMB STRAIGHT TO THE HEADERS VIA A T-VALVE? RIGHT NOW I HAVE THE BASSETT VALVE THAT OPENS AT ABOUT 1500RPM WATER TO THE HEADERS. I CONTROL THE TEMP BY REDUCING THE WATER EXIT VIA A GATE VALVE. READING ALL THESE DIFFERENT APPLICATIONS LEADS ME TO BELIEVE THAT RESTRICTING THE OUTLET IS NOT GOOD. I ALSO CONTROL THE WATER IN VIA A GATE VALVE,TOO MUCH AND WATER TO THE HEADERS TOO LOW AN RPM.

[LVjetboy]

Jimsride, flow to headers splits off after the 1/2" hardline valve and before a 3/8" valve I labeled "Main header coolant control" in diagram. The 3/8" valve is actually located on the engine coolant line. With this valve I can backpressure the Bassett spring t to adjust rpm injection point...without backpressuring the engine in the process, as with a dump valve controlling injection rpm. I have a t-rex thermostat, so the 1/2 and 3/8 valves are used to control block pressure and injection point, but have little affect on temperature.
Your setup sounds like the Bassett web site cooling diagram. If it's working well for you then no worries. As Oldsquirt mentioned, lots of jets are plumbed that way and work fine. My comments on a gate restricted outlet are just my personal bias. In your case, without a thermostat, either design will require you to balance flow between two valves to hit the right combo of temp and injection point.
jer