Hey guys - I'm planning on doing the TB coolant bypass on of the next couple of weekends. Just a few quick questions for anyone that's done it before:

1) Do I have to drain any coolant first. I'm not too familiar with cooling systems...not sure if there will be coolant up that high when the motor is cold.
2) I read under the article under the tech section of this website that a piece of copper tubing should be used to splice the 2 hoses together when you bypass. I have a plastic hose splice kit at home that is the right size. It's a heater hose repair kit I believe. Would that work fine? Are heater hoses subjected to the same levels of heat as the rest of the system?
3) I live in NJ with fairly strict emissions and have inspection coming up next month. This mod shouldn't affect emissions at all, right?

Thanks!!

 

1 Yes.

2 Plastic should work just fine.

3 Only a visual

 

2) Plastic connector is fine, but better solution is eliminating the connection all together. Use a question mark shaped hose to connect the intake fitting directly to the diverter valve. The part number has been posted here in the past. Or, you can walk into a parts store and check the hoses until you find one that's shaped the way you like it

 

1.No.......

 

There is only the amount of coolant in the throttle body itself that will leak out after you take the hoses off. A few paper towels underneath will catch that.

This won't effect emissions at all. The purpose of having coolant run through the throttle body is to prevent icing in severe weather while going down the highway. I've driven my car to work in 25°F weather with the TB bypass and had no issues. If I lived in -30° weather, I'd leave the system hooked up.

The air temperature won't be that much different going into the engine either way. If it's 80° outside. You have 80° air going into an engine, which then gets heated up to engine temp. With the TB still hooked up, you have 180° coolant warming up the surrounding space around the 80° air going into the engine before it gets warmed up to engine temp.

 

What wasn't said here, unless I missed it, is that you should do the bypass because it's less to worry about. Take the hoses out completely. I don't have a diverter valve and I agree with the question mark looking hose which can be found at NAPA. Other parts stores might have them but I go to the closest store because I'm too lazy to shop around and I'm not a big fan of VatoZone. That's just me though.

 

Maybe just buy one of these and cut an inch off of each end to replace the whole hose?

Dayco/Hose (Upper)

Part Number: D87658
Alternate Part Number: M-4508

This DaycoŽ Small I.D. Molded Heater Hose is designed to replace OEM coolant hose and provide long, reliable service. The single molded configuration eliminates the need for multiple connections of hoses and clamps.
• Made with a tough EPDM rubber compound this hose will resist the detrimental effects of heat, ozone and impacts from road debris
• This hose meets SAE J20R4, Class D1 and SAE J1684 Type EC specifications
• Highly resistant to electro-chemical degradation and premature stress cracking of the tube
• The knitted polyester reinforcement provides high burst strength and resists degradation from temperature extremes and moisture
Part Number: D87658
Weight: 0.375 lbs
Coolant Hose Color/Finish: Black
Coolant Hose Heat Shield Included: No
Coolant Hose Length (in): 12
Coolant Hose Material: EPDM
Coolant Hose Protective Sleeve Included: No
Coolant Hose Type: Single I.D. (Inside Diameter)
Hose End (1) Inside Diameter (in): 0.63
Hose End (1) Outside Diameter (in): 1.005
Hose End (2) Inside Diameter (in): 0.63
Hose End (2) Outside Diameter (in): 1.005
Maximum Working Pressure (psi): 50