Did bypassing my heater core cause my radiator to blow?

[Evancox]

I have a 95 mustang and the radiator blew, I finally have enough for a new radiator but i dont want to buy one and thrn have it blow after 20mins. Have you guys heard of this happening before. I just think it was a wierd coincidence that it blew right after bypassing the heater core. Thanks

 

[cobrajeff96]

Maybe you introduced air pockets into the system when you did the bypass. Old stock radiators aren't trustworthy past a certain amount of years/miles, with those plastic end tanks. Bypassing the heater core in and of itself doesn't change anything other than not having heat inside the cabin. The entire system pressure remains the same and the only thing that can change it is the pressure rating of the radiator cap (or the reservoir cap if the system uses a reservoir AKA degas bottle).

 

[ttocs]

I had one on my car for 2 years while I lived in phoenix. Heaters are not as important out there but radiators are. Never had a problem with min and the stock rad was almost 20 yrs old by then.

 

[Evancox]

Maybe you introduced air pockets into the system when you did the bypass. Old stock radiators aren't trustworthy past a certain amount of years/miles, with those plastic end tanks. Bypassing the heater core in and of itself doesn't change anything other than not having heat inside the cabin. The entire system pressure remains the same and the only thing that can change it is the pressure rating of the radiator cap (or the reservoir cap if the system uses a reservoir AKA degas bottle).

Ok thanks alot so a new radiator shouldnt blow cuz of that right?( ima get all aluminum) its leaking out where the small v like lines are in the center of the radiator yk what i mean? Its just a small part of it leaking. Ima replace the radiator and hopefully it last. Any radiator brand that you recommend or should i just go with lmr?

 

[weendoggy]

Those are the heat transfer tubes in the radiator and the ones that usually leak at some point. The other being the side tank seal (plastic tanks) and if you go with all aluminum (good choice) that should be a non factor. Just flush the system every three to four years.

 

[Evancox]

Those are the heat transfer tubes in the radiator and the ones that usually leak at some point. The other being the side tank seal (plastic tanks) and if you go with all aluminum (good choice) that should be a non factor. Just flush the system every three to four years.

I wish it was just the plasic so i could jb weld it temporarily lol

 

[shovel]

bypassing the heater core would never cause the system pressure to change, that's regulated by the radiator cap.

 

[ttocs]

isn't there a small restrictor that goes inside the core or the pipes going to it? I thought I read about that at some point....

 

[96blak54]

I know 100 percent there needs to be a restrictor in the feed line to the heater core with a modular engine. The stock heater core feed hose has one and there are aftermarket ones you simply push into the hose on the engine side supplying water and use a clamp to keep it stationary. If a restrictor is not used, such as in my case with the 5.4l swap, the stock feed hose wouldnt work due to extreme bends, so I browsed the part store for a hose that I could make work. Two burst hoses later, I revisited the stock hose to discover a restrictor. I made an aluminum restrictor, slipped it into the feed hose(on the end that fits to the engine) and clamped it in place and never had a burst hose again

 

[96blak54]

 

[shovel]

I'm pretty sure the restrictor is just there to reduce the possibility of noise from the heater core by limiting speed. The impeller isn't generating dynamic pressure on a scale that matters relative to the expansion pressure that the rad cap regulates.

 

[cobrajeff96]

FWIW, I've been running open AN lines to the heater core for over two years now and the particular hoses I use are definitely not as tough as OEM rubber as far as wall thickness.