Drilling a Hole in Intake manifod
 

Need help please.

i just received my carb engine and it's set up for a serpentine pully system.

my question is... has anyone had to drill a hole in the bottom of the termostat housing placement for an inlet for the hose coming up from the circulating pump. on my 7.4l MPI it had an inlet in the intake manifold for this hose but with the Dart manifold which is on the new motor it does not have one. do i have any other options, or drilling is the only way.

i was tiold the the inlet has to be under the termostat housing . i will post pics if needed or u can look at the velocity thread under prop selection.

thanks

Is this for the by pass hose? And it is also only an issue if you are using the thermostat. No thermostat, no need it.

Jeff,

yes it's for the bypass hose, and i was putting a thermostat in it.

do i have to go this route?
thanks

I don't use thermostats. Unless there is a specific reason that you want to put one in, I would leave it out.

That fitting is so that the exhasut does not run dry when the thermostat is closed. You can plug the pump, and this will increase youre water flow through the engine.

jeff

here r some pics. so if i block the top of the circulating pump, what type of thermostat housing can i use.
i was going to use the standard mercrusier one. would it still work. and i would i get a reading...

do u have any pics i can look at.


thanks

If you have the later model Merc t-stat that looks like picture below, then you do not need to run the recirculating pump to intake manifold bypass. The t-stat housing does not block the flow coming out of the engine like the old style t-stat housings. It merely uses the t-stat to change water direction. Again, it does not block it.

http://images.westmarine.com/large/6937114_hiRes.jpg

This is the T-housing i was going to use. so i'm just trying to figure a way to plumb the water system, where by i don't have to drill to put the bypass underneath the t housing & thermostat.

if u guys have any pics i could see that would be great..

thanks

Drill the manifold and use the bypass

Ditto...
It is also "not" required with the aftermarket unit.
Here shown with the later model Merc unit and aftermarket unit.
Plug it...

I started typing a long response to my studying of this system and just realized I posted this info elsewhere a while ago. Sorry for the link but I said more then (quite detailed) than I could probably do now. Has pics to show water direction also.

Hope this helps.

Post #62 at:
http://marineperformancetechtalk.com...sg5077#msg5077