New motors Hot on Test stand ...
07-30-2007, 11:27 AM
#21
07-30-2007, 11:48 AM
#22
Geronimo36
Gold Member
Your setup is confusing....
Why do you have a hose coming from the raw water pump up to the thermostat housing, then a hose running from the thermostat housing back down to the crossover, then you have the bypass hose from the thermostat housing back down to the crossover.
Typically, any system with a crossover has water going from the raw water pump to the oil cooler, then a hose from the cooler "directly" to the crossover. If using a thermostat you then have a small bypass hose going from the crossover up to a "tri-y type of stainless neck on the intake manifold. From there the other two conections of the "tri-y" go to your exhaust manifolds.
Why do you have a hose coming from the raw water pump up to the thermostat housing, then a hose running from the thermostat housing back down to the crossover, then you have the bypass hose from the thermostat housing back down to the crossover.
Typically, any system with a crossover has water going from the raw water pump to the oil cooler, then a hose from the cooler "directly" to the crossover. If using a thermostat you then have a small bypass hose going from the crossover up to a "tri-y type of stainless neck on the intake manifold. From there the other two conections of the "tri-y" go to your exhaust manifolds.
07-30-2007, 09:28 PM
#23
Registered
Thread Starter
Your setup is confusing....
Why do you have a hose coming from the raw water pump up to the thermostat housing, then a hose running from the thermostat housing back down to the crossover, then you have the bypass hose from the thermostat housing back down to the crossover.
Why do you have a hose coming from the raw water pump up to the thermostat housing, then a hose running from the thermostat housing back down to the crossover, then you have the bypass hose from the thermostat housing back down to the crossover.
Today I change the plumbing straight to the crossover and capped the 1.25 and 1.75 outlets ...
On the other motor I added the circ pump ... then ran both motors ....
The motor with the circ pump came up to 140* pretty quickly ....after a while it was at about 160 and settled there ... The heads were at 125* ..with my original setup they were 190*+ ... Pressure off the block was less than
10bs up to 2000 rpm .... at 4000 rmp was close to 30lbs ...
The crossover motor really never came up to ANY temp ..maybe 100* .. Pressure at the block was zero to 3lbs at 4000rpm ....head temp 95*
The circ pump motor seemed real comfortable .... The crossover motor seemed ok ... Prob no difference just in my mind warm is better ...old school I guess ...I'm thinking the crossovers with oil thermostats at 200*+ might work well .. m
Last edited by offthefront; 07-30-2007 at 09:36 PM.
07-30-2007, 10:03 PM
#24
Ginger or Mary Ann?
Charter Member
Have you tried it w/o the bypass hose for chits and grins?
The T-stat housing has 4 internal chambers with sized openings to control flow direction to divert the flow depending on the Tstats status. Not sure you can mix and match a stock housing with a cross over. It's more complicated than it appears.
Just thinking outloud, but with the crossover and bypass hose setup, cold water will go up the bypass hose from teh cross over to the bottom of the t-stat giving it a false motor temp reading.
In the stock setup, water flows from the intake into the waterpump, (the opposite flow direction you are doing) and then is recirculated thru the motor.
A normal cross over/Tstat housing setup dumps the cold bypassed water from the cross over into the discharged side of the housing and out to the exhaust not effecting the Tstats workings.
The T-stat housing has 4 internal chambers with sized openings to control flow direction to divert the flow depending on the Tstats status. Not sure you can mix and match a stock housing with a cross over. It's more complicated than it appears.
Just thinking outloud, but with the crossover and bypass hose setup, cold water will go up the bypass hose from teh cross over to the bottom of the t-stat giving it a false motor temp reading.
In the stock setup, water flows from the intake into the waterpump, (the opposite flow direction you are doing) and then is recirculated thru the motor.
A normal cross over/Tstat housing setup dumps the cold bypassed water from the cross over into the discharged side of the housing and out to the exhaust not effecting the Tstats workings.
07-30-2007, 10:11 PM
#25
Ginger or Mary Ann?
Charter Member
Without the restrictor I was seeing 5-7lbs but it never got past 100*. With the restrictor I'm getting 115-120*. Oil stays right there with it. I was going to put a pressure relief valve on it for 25lbs... I could probably drill the restrictor out some to lower the pressure.
Install the Merc press relief valve and you will be set. You can run a t-stat to control the temps, while the valve controls the pressure.
07-30-2007, 10:17 PM
#26
Looks like US1 is on to something... but you'd think the cold water entering the manifold right under the t-stat might never let the t-stat open (?)
Is there a t-stat in the crossover motor?
Is there a t-stat in the crossover motor?
07-30-2007, 10:34 PM
#27
Ginger or Mary Ann?
Charter Member
Yes, that is throwing me off too. Then I was thinking that the cold bypassed water going into the intake and into the stat housing was also giving a false cold reading since both gauges would be reading this colder water, but also causing the stat to stay closed or at least not fully open which might account for the high engine temps reported in the original post.
I think it'd be easier to just install a T-stat housing made for such use. Even removing the bypass hose and the t-stat using the stock housing may be questionable do to the internal passages flow routing. I don't know.
BTW, I had the exact same extremely high pressure problems using the stock housing, pump, everything. My only cure was to install the relief valves before the stat housing. Both motors, same thing. It's a design flaw in my opinion. The older housing that used the brass tee/ball assembly was perfect.
I think it'd be easier to just install a T-stat housing made for such use. Even removing the bypass hose and the t-stat using the stock housing may be questionable do to the internal passages flow routing. I don't know.
BTW, I had the exact same extremely high pressure problems using the stock housing, pump, everything. My only cure was to install the relief valves before the stat housing. Both motors, same thing. It's a design flaw in my opinion. The older housing that used the brass tee/ball assembly was perfect.
Last edited by US1 Fountain; 07-30-2007 at 10:43 PM.
07-31-2007, 07:01 AM
#28
Registered
Thread Starter
I guess I'm still thinking the bypass will let water re circ thru the motor but US1 is right ..no way water is flowing down from the intake to the crossover against the sea pump pressure .... I will pull the bypass and see what we get .. m
07-31-2007, 08:08 AM
#30
Geronimo36
Gold Member
No thermostat ...just the outer ring of the thermostat ..
I guess I'm still thinking the bypass will let water re circ thru the motor but US1 is right ..no way water is flowing down from the intake to the crossover against the sea pump pressure .... I will pull the bypass and see what we get .. m
I guess I'm still thinking the bypass will let water re circ thru the motor but US1 is right ..no way water is flowing down from the intake to the crossover against the sea pump pressure .... I will pull the bypass and see what we get .. m
You need to buy one of these; http://www.stainlessmarine.com/thermostat6.html
If you run the crossover without a thermostat you won't build any water temp and don't need the bypass hose.
Last edited by Panther; 07-31-2007 at 08:10 AM.
