Bypass heater core on 720

[Macklen]

Hi.

I need to bypass the heater core on my 85 720 permanently.

One hose to the heater core goes from the bottom of the intake, from a metal piece with two outlets.

The second from another single outlet coming from the block itself behind the oil filter.

Can I connect these two water takes or is it better to just cap them?

 

Also, both hoses seem the same size, I overlooked to mark which goes where when I took the head off for machining.

Is there a flow direction in the heater core?

I'll be removing the whole heater core assembly from the dash anyway, it's leaking a bit and it never gets cold enough to need heating where I live.

Thanks.

 

[datzenmike]

You can join the two hoses but NEVER without blocking the flow. Maybe join with a wooden dowel with hose clamps?

 

If permanent why not remove the elbow in the block and put a pipe plug in there so no chance of the hose failing or leaking?

[Macklen]

Thanks for the reply.

I thought about that but t's so corroded I'm afraid it's gonna break and leave a piece in the hole. It happened to the Y piece under the intake and after cracking the intake trying to get it out I had to get another intake from the junkyard. It REALLY was stuck in there.

 

Maybe just cut the hoses nice and short and plug them. Heater core is out now. Took a few grunts and two units of blood but it's out.

Thanks Mike, you the man.

 

[Thomas Perkins]

I couldn't find a new heater core so I got a new custom made heating and air.I did by pass the core for a while.What I did was connected the two hoses together with that metal connector piece with 2 clamps.All my old stuff is all gone.I mean everything.

[datzenmike]

Most of the time just connecting them together isn't a problem. With a heater core, when not used, the flow is shut off. By connecting together, you are running hot water from the block right back into the water pump with out any cooling by the heater core and certainly not through the rad. In effect you are by passing all that hot water around the radiator. On hot days this just ads an additional load on the cooling system.