Blocking or Bypass of Heater Core lines, which one's better?

**jvnj** · April 6th, 2016 12:57 PM

My ageing Corolla had its Heater core leaked, and was forced to just remove it thinking that it was a good idea since we really don't need heaters in our country. I was also aware of the cost if it need replacing, thus the removal. I temporarily blocked the supply hoses using the available plugs in the market. My dilemma is that I really don't know which one is better, Blocking or Bypassing. Some say plugging will cause restriction in coolant circulation (if the thermostat is closed), while Bypassing reduces pressure in the system. I don't know which one's best for my engine.

I will appreciate thought regarding this. Thank you!

**lowslowbenz** · April 6th, 2016 01:08 PM

Bypass.

Jury rig a pipe with flexible extensions on both ends for it.

I have old cars too, all are bypass.

**JohnM** · April 6th, 2016 01:21 PM

Originally Posted by lowslowbenz

Bypass.

Jury rig a pipe with flexible extensions on both ends for it.

I have old cars too, all are bypass.

Is bypass better than capping off the inlet and outlet? My old car was factory bypassed (got clogged and had very hard to detect pinholes) and my friend's car of similar make was capped (leaked too but kinda easier to check).

**lowslowbenz** · April 6th, 2016 01:32 PM

^

I'd like to think so. My bypass tubes are all outside already (engine bay) where its easy to check should they leak. The system holds a bit more coolant too (as compared to a plugged one), so I think that's one benefit there.

**JohnM** · April 6th, 2016 01:45 PM

I think most Japanese FWD engine designs route the bypass under the intake manifolds between the block and the firewall.

**jvnj** · April 6th, 2016 02:16 PM

Originally Posted by lowslowbenz

^

I'd like to think so. My bypass tubes are all outside already (engine bay) where its easy to check should they leak. The system holds a bit more coolant too (as compared to a plugged one), so I think that's one benefit there.

Ah yes, a bit more coolant. Thanks for your comments, Sir LSB!

**dreamur** · April 6th, 2016 02:48 PM

The shop did that to the jimny when they replaced the compressor. They bypassed the heater tubes.

Sent from my SM-N910C using Tapatalk

**jvnj** · April 6th, 2016 05:14 PM

Originally Posted by dreamur

The shop did that to the jimny when they replaced the compressor. They bypassed the heater tubes.

Sent from my SM-N910C using Tapatalk

I remember, it was the same process (Bypass) done to my Delica before. I guess I have to do the same with the Rolla before letting her go

Thanks dreamur!

**jaypee10** · April 6th, 2016 06:50 PM

bypass mo nalang ..
sa akin sa civic ko nag leak sa loob kaya ginawa ko binaypass ko nalang wala namang epekto sa cooling system.

**Stigg ma** · April 6th, 2016 08:50 PM

Originally Posted by jvnj

My ageing Corolla had its Heater core leaked, and was forced to just remove it thinking that it was a good idea since we really don't need heaters in our country. I was also aware of the cost if it need replacing, thus the removal. I temporarily blocked the supply hoses using the available plugs in the market. My dilemma is that I really don't know which one is better, Blocking or Bypassing. Some say plugging will cause restriction in coolant circulation (if the thermostat is closed), while Bypassing reduces pressure in the system. I don't know which one's best for my engine.

I will appreciate thought regarding this. Thank you!

blocking, just like what we have with the vios, 1 & 2 nz-fe have pipes from the water pump going to the heater core in the cabin... but since the vehicle in the philippines are not fitted with a cabin heater core, said pipes are blocked by a rubber plug...

if you maintain a good coolant system it shouldn't be a problem...