Bypass Heater Core, 3.8 hose leaks 72 Chevelle

Hello all. The heater coil leaks so I bypassed it by going with a short 3/8 hose between the water pump and radiator and the water pump end of the hose leaks. Afraid of over tightening the clamp at the water pump end. Does someone sell a coupler to connect a 5/8 and 3/4 hoses or is there a way to stop the leak at the 5/8 end? Thanks for any replys.

You can get a 3/4 to 1/2 copper reducer at any plumping supply, lowes, home depot, etc.

Hello all. The heater coil leaks so I bypassed it by going with a short 3/8 hose between the water pump and radiator and the water pump end of the hose leaks. Afraid of over tightening the clamp at the water pump end. Does someone sell a coupler to connect a 5/8 and 3/4 hoses or is there a way to stop the leak at the 5/8 end? Thanks for any replys.
http://coldhose.com/ Search heater hose fittings.

Hello all. The heater coil leaks so I bypassed it by going with a short 3/8 hose between the water pump and radiator and the water pump end of the hose leaks. Afraid of over tightening the clamp at the water pump end. Does someone sell a coupler to connect a 5/8 and 3/4 hoses or is there a way to stop the leak at the 5/8 end? Thanks for any replys.

copper water tubing fittings will allow you to connect the 2 different sized hoses. you may find plastic fittings but these may not be able to handle the heat.

I got a 5/8 to 3/4 straight heater hose splice (plastic) from NAPA. Ran it for 6 months without issue. It's out now because I replaced the heater core in the '65 4-4-2.