By-pass trick question
Thread Starter
Racer
Joined: Mar 2012
Posts: 476
Likes: 37
From: Lynnwood WA
By-pass trick question
I am trying to figure out where each hose comes from and goes to, for the throttle body by-pass. I have a 86 engine with TPI in my 79 C3. On the front of the TPI, on the bottom of the throttle body is a hose that loops from the TB to the intake manifold. As near as I can tell I am supposed to remove this hose and run one of the heater hoses to it's fitting, the looped hose's lower fitting on the manifold. Is this right? And if so which heater hose? Does it matter which heater hose goes to the intake and which one goes to the water pump? Wow that's clear as mud.
Is this the fitting?
Thanks
Zorro
Is this the fitting?
Thanks
Zorro
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Not even worth messing with.
On my prior '88 I bought a "U" shaped hose, ran it from intake base back behind the A/C compressor to hide the splice into heater hose.
On this '88 I just cut back the OEM hose from the intake base, ran the heater hose under the AIR pump hoses and did the splice behind/below the AIR pump; it was damn cramped but now still have the OEM heater hose with no visible splice unless I remove the TB.
And, yes, that rusty-ended fitting looks like the one to which you need connect the heater hose.
BTW, I use black rubber nipples over the old in/out ports on the TB to dress up those now unused coolant ports.
Thread Starter
Racer
Joined: Mar 2012
Posts: 476
Likes: 37
From: Lynnwood WA
I just did this mod and the main reason was to avoid the coolant drain every time I want to remove the TB...
On my prior '88 I bought a "U" shaped hose, ran it from intake base back behind the A/C compressor to hide the splice into heater hose.
On this '88 I just cut back the OEM hose from the intake base, ran the heater hose under the AIR pump hoses and did the splice behind/below the AIR pump; it was damn cramped but now still have the OEM heater hose with no visible splice unless I remove the TB.
And, yes, that rusty-ended fitting looks like the one to which you need connect the heater hose.
BTW, I use black rubber nipples over the old in/out ports on the TB to dress up those now unused coolant ports.
On my prior '88 I bought a "U" shaped hose, ran it from intake base back behind the A/C compressor to hide the splice into heater hose.
On this '88 I just cut back the OEM hose from the intake base, ran the heater hose under the AIR pump hoses and did the splice behind/below the AIR pump; it was damn cramped but now still have the OEM heater hose with no visible splice unless I remove the TB.
And, yes, that rusty-ended fitting looks like the one to which you need connect the heater hose.
BTW, I use black rubber nipples over the old in/out ports on the TB to dress up those now unused coolant ports.
What got me started on this, was swapping TBs three times in the last month. Resetting the TPS, IAC and TV cable was bad enough without dealing with the coolent. Thanks for the conformation on the rusty fitting. That gives me a place to start.
Zorro
Team Owner
Joined: Dec 2000
Posts: 21,094
Likes: 282
From: Phila., PA burbs
For this reason alone it was well worth it. When I did mine I didn't use any connectors. I got one piece of heater hose that was long enough to go straight from the heater core to the intake manifold.
Le Mans Master
Joined: Nov 2009
Posts: 6,882
Likes: 234
From: Bangkok, Thailand
Thread Starter
Racer
Joined: Mar 2012
Posts: 476
Likes: 37
From: Lynnwood WA
Zorro.
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Team Owner
Joined: Mar 2012
Posts: 27,118
Likes: 135
From: Montgomery, Alabama
2017 C6 of Year Finalist
The bypass on mine is done the same way with one solid hose. Joining the two hoses with a splice section leaves too much possibility for leakage.
Le Mans Master
Joined: Nov 2009
Posts: 6,882
Likes: 234
From: Bangkok, Thailand
