I am going to be helping a friend replace all of the coolant hoses on his 94 Vette. I remember discussions on going back with 95 hoses on a 94 and doing the TB by-pass at the sametime to clean up the engine bay. Anyone have any info on this?

 

The lower radiator hose is the same on all, you only need to change the existing upper three piece combination (two hoses and tee) part numbers below.

The small hose from the tee in the upper rad hose goes to the port on the left side of the throttle body (inlet) remove the hose and cap the port on the throttle body,(rubber caps available at a parts store) then install the 95/96 one piece upper radiator hose.

The second part of the mod (or at least the way I did mine) goes like this. The early design has a second tee in the surge tank outlet hose, the hose from that tee connects to the outlet hose on the right side of the throttle body, the main surge outlet hose connects to the highest small port on the water pump.
Remove the throttle body outlet hose and cap the port at the throttle body using another rubber cap.

There are several ways to address the tee remaining in the surge outlet hose, cap the tee using another rubber cap, remove the tee and replace it with an inline coupler available at a parts store, or just install a one piece hose from the surge tank to the water pump using roll stock hose (3/4" ?)

Lower radiator hose (all)
10257252 (GM)
22464 (Gates)
24409L (AC Delco)
71646 (Dayco)

Upper radiator hoses (early)
10258276 (GM)
10258277 (GM)

Upper radiator hose (95/96=one piece)
10278338 (GM)
22463 (Gates)
24408L (AC Delco)

 

 

Should be the same as my '93. Copied from an earlier post:

On my LT, I was able to use the following hoses to eliminate the 'tee'. Makes for a cleaner install. Then get a couple tube caps in the Help! section at the Zone and cap off the open tb tubes. I'm pretty sure the p/n's are NAPA.

NBH9097 - Lower Radiator Hose – Standard 1993 hose. Routes from the lower radiator to thermostat housing.

NBH9096 - Upper Radiator Hose – 1995 LT hose. Eliminates ‘Tee’ to TB. Routes from the upper radiator to the water pump housing.

NBH11743 - Heater Hose – Standard 1993 hose. Upper surge tank outlet to upper heater core inlet at firewall.

NBH11719 - Heater Hose – 1995 LT hose. Routes from the lower surge tank connection to the upper water pump housing.

NBH10729 - Heater Hose – Standard 1993 hose. Routes from the heater flow control valve to the lower water pump housing.

NBH9808 - Heater Hose – Standard 1993 hose. Routes from the lower heater core inlet to the heater flow control valve.

 

Jim, thanks for the info. It looks as simple as using a 95/96 upper radiator hose and then just replacing the 3/4" heater hose with a solid one piece hose. I think we will go that route since it is cheaper and eliminates a number of possible leak points.

 

If you look at the previous threads on the subject you'll find the GM p/n for the 95 heater hose.

 

Exactly.

 

I have a 92 and couldnt figure this out. I had the U hose from the radiator cap tank to firewall. Then a 1 inch from tank to 3/4 wp heater hose used hose connector to reduce. and a 3/4 heater hose from the firewall to WP.Am i missing something? the heater core or surge tank wouldnt have a hose on it

 

Pretty sure 92 has a one year only water pump, the fittings are different, may even be an extra one so of course the hose routing is not the same but I am not sure how exactly, sorry.

 

On my '93, after the TB bypass conversion there are 2 heater hose lines running from the base of the surge tank. The upper line is U shaped and runs to the heater core. The lower line runs to the thermostat housing.



Another heater hose runs from the heater core to an in-line flow control valve and on to the base of the water pump. That hose is to the right near the plug wires in this next pic.

 

LOL. I always get stuck with cars that have these one year options.

Darn Dang

 

Thats a great help to the thread, probably couldnt have got where we are without ya mate

 

Hi wanted to chat with you about this as you really sem to know what is up with the 93's

 

Interesting info guys. What's the advantage to doing the TB bypass on a 94? Is is just an appearance thing?

 

It makes a nice improvement in appearance by 'uncluttering' the engine bay. It also eliminates a few possible leak points and lastly it is also the best way (IMO) to do the TB by-pass.

 

I am going to do this since my on the upper hose is rusted out and I don't feel like going to the dealer to get one and pay $40.

Thanks!
Monk

 

I have seen some blue ones on ebay that looked nice don't know how good they are. Just looked they have red ones too.

It is better to start a new thread than to bring up a old one.

 

Pull the knock sensors to do a proper flush and use the spring clips not the screw type.