Heater pipe delete - sensor relocate?

[Darkwriter77]

Heater core's been shot for ages, been running a nice copper-tubing U-turn at the end of the stock hoses as a bypass. The heater pipe, itself, has begun to give up the ghost, now, and is getting a teeny tiny bit of seepage betwixt its upper and lower halves (right ahead of the front EGR spacer line fitting). My options: 1. Replace the heater pipe with a new one from 50resto.com and throw on a nice new U-bend hose at the back, or 2. Remove the whole heater pipe assembly, altogether, and relocate the coolant temp sensor to another happy home.

Okay, obvious problems are going to be where to stick the coolant temp sensor in lieu of its fitting in the heater pipe, what to do with the fittings for it coming off of the water pump, and what about the open hole on the intake manifold?

I was first thinking of just threading the coolant temp sensor right into the intake manifold, but I'm assuming I can't just dead-end that port, because that's either a main supply or return route for the coolant. That, and I'm sure the temp sensor doesn't even have the same thread size/pitch. So, maybe a standard pipe thread brass fitting with a barb end, going to a thick (5/8"?) hose that loops around back to the water pump?

Anyone deleted the heater pipe, completely? Or does everyone just run the good ol' ghetto-engineered U-shaped hose reroute kind of gig at the tail end?

 

[TheUser]

Have you considered patching the seepage point on the heater pipe w/ JB Weld? If it's just a small hole, that would most likely do it.

I don't think the coolant returns to from the heater pipe since it isn't supposed to be cooled (heater needs to be hot). Rather, the return comes from the thermostat housing to the water pump. I suppose you most likely could get a pipe fitting and place it in the intake and put the sensor in it - I don't know why it wouldn't work since all the sensor does is sense the temp. of the coolant.

However, every time someone talks about deleting the pipe, they are told not to because of the sensor, so I'm not sure if anyone has tried to attach the sensor directly to the the lower intake via a fitting or not.

Lets see what others say.

 

[jerryD]

just get a bung to put the sensor in the lower intake where the tube would go. it works fine. the line from the t-stat to pump should be hooked up. just need to plug the other outlet on the pump somehow.

 

[Darkwriter77]

Threading the sensor into the intake would be easy if I knew exactly what the size/thread on the intake side is - the sensor's size/thread would be easy enough to get, as I need to put a new one in there, anyway. Anyone happen to know what kinda size the pipe threading into the intake might be? The thing's deteriorated enough that I'm no so sure it wouldn't just snap or leak like a mofo if I tried to remove it and put it back on...

Think I could get away with just pushing on a simple heater plug (it's either 5/8" or 3/4") and cinching it down with a hose clamp? ... or would there be enough pressure at WOT to pop that sucker off of there or make it burst?

 

[darthcual]

My buddy did this exact thing on his 88. He took all the hoses that run out of the intake, up to the heater core completely out and used a bung with acrilyc tape to seal it all up. As for the temp sensor I have no idea, I will ask him and post it later. The water pump, he used a vacuum cap.

 

[Darkwriter77]

Cool beans. Now, all I need is the thread/size of the ... hehe ... BUNGhole in the intake so I can either search for an adapter or, better yet, just thread the coolant temp sensor right into the thing. (For years, I have searched for a way to include the word "bunghole" in an automotive conversation. At last, it has come to fruition! )

Btw, though I am quite fond of JB Weld (and its handy little brother, JB Quick), I'm not so sure it would stick for long-term use. Besides, I'd still have to remove the pipe to properly scrape/sand it down and clean it to prep the surface so it'd get a good enough bond to stay on there permanently ... and then I'd have to paint it with some high-temp black so it wouldn't look horribly ghetto (unlike the rest of my car ...heh).

Just got to thinking ... if I cap off the intake's port where it normally would flow out to the heater, how is the coolant going to that portion of the motor going to actually flow, in order to actually get a proper reading? I mean, it WOULD get heated by the time things got up to 190* or so, just by heat transfer in general throughout the motor's connected metal parts, but it seems it'd take that much longer for it to send the ECU into closed loop mode, right...? I may have to give this a tad bit more thought. Don't wanna blow fifty bucks on a new pipe just so I can put a loop on the end of it...

 

[jerryD]

dunno the size it needs, but just take your heater tube and sensor to the hardware store to get the right sizes. if you or a buddy has a intake around take that.

 

[Darkwriter77]

That's just the problem: I can't take it off and just drive on over to Ace Hardware or Home Depot, as it's my only form of transit (when m'lady is at work). The size for the sensor would only necessitate that I have to bring the new sensor along, but alas, I have no local buds to loan me a ride and/or a spare heater tube/lower intake manifold to get size measurements.

It wouldn't by chance happen to be the same size as the temp gauge sending unit on the opposite side of the manifold, would it? I do have a spare sending unit sitting around that I could use to size it up against...

 

[PonyPower96]

sorry to butt in but what if you have a car that had all this done and wanted to put the heat back in. This is my situation and my car has no heater tube. The heater core supposedly still works, the previous owner was just trying to clean up the engine bay because it was only a summer car. Is there anywhere i can get a diagram of the stock setup and the part numbers i need?

 

[timewarped1972]

that heater tube assebly it self is part# lrs9424b in the 5.0 resto catalog and it's 75 bucks......i'm sure if you can get that some one can post some pics if a diagram isn't available although my guess would be some one on here has one......lol...

 

[stangnutlx]

that heater tube assebly it self is part# lrs9424b in the 5.0 resto catalog and it's 75 bucks......i'm sure if you can get that some one can post some pics if a diagram isn't available although my guess would be some one on here has one......lol...

heres an easier way to remove the Molded metal heater tube and still have heat....


Goto NAPA order the factory molded heater hose for an 85 GT it goes from the lower part on the waterpump to the heatercore. Then for the Coolant Temp sensor use a fitting from Russell, Earls, or Aeroquip to install between the hose from the waterpump to the heatercore. Then plug the hole in the intake....

Works good!

 

[jerryD]

you can get the tubes off of ebay for like $10-20 all day long. just find a clean one and get that one.

 

[darthcual]

Dark, since your not sure what size i say buy several. I mean you can never have to many bungs laying around. Their is always a HOLE to stick them in, right?

 

[Darkwriter77]

I have too many BUNGholes at my job site, as it is!

So, as far as the above detailed NAPA hose thing, are we talking about an adapter such as the one used for, say, my Autometer temp probe, where one brass fitting threads into a sort of "sleeve" for the other? Or using a simple pipe plug on the intake and then getting some kind of T-connector with a female port to thread the sensor into? Or ... ummm ... that's got me all confused.

Thus far, the simplest solution seems to be to just yank all the heater tube stuffs, plug the water pump outlet, and somehow thread the sensor into the intake with the creative use of some kinda adapter thingymadoohickey. Trouble is, looking 'round my local Ace Hardware today, I found no such animal to do the trick, nor at my workplace (Autozone). NAPA guys just looked at me like I was talking about space aliens when I tried them. Any others?

 

[Darkwriter77]

Okay, finally got around to doing this. For anyone else wanting to do it, here's all you'll need:

- (1) 5/8" rubber bypass (heater) pipe cap
- (3) 1/8" vacuum caps
- (1) brass adapter bushing, Autozone part #321108 (not sure on the exact inner/outer measurement)
- Teflon tape
- Big-arsed Crescent wrench or a sturdy 1 1/8" open-end wrench

Being that my old heater pipe had just about rotted itself out completely - half of it fell apart in my hands as I tried to maneuver it out - I wound up mutilating the thing a bit in the process of removal by breaking off the small line fitting going to the EGR spacer and snapping off the rear bolt bracket that presumably either kept it bolted to the manifold or allowed for a hole into which one of those plastic pokey-fitting things was inserted for the fuel injector wiring harness's wire loom. (Whew ... long sentence!) I also had to smoosh the ends together that are spaced apart (front- and rearmost parts) to wiggle it under the fuel rail, which was the main headache of the whole deal.

At the very least, you'll need to unhook the radiator hose, the throttle cable linkage/bracket, and the throttle body air supply elbow/tube - if you wanna keep the heater pipe intact for possible later use/sale, you're gonna have to remove the entire upper intake manifold and fuel rail assembly, which involves the purchase of another upper plenum gasket and maybe some injector O-rings.

With all the old crap off, cap the heater pipe on the water pump and secure it with a hose clamp, and ditto for that little bugger of a hose fitting way on the back of the intake manifold (the hose that used to be the coolant return line for the EGR spacer), or remove that nipple fitting and thread in a pipe plug, instead - your choice. Throw some Teflon tape on the brass bushing, clean the threads of the intake out where the pipe used to thread in, crank that puppy in there, and then Teflon up and thread in your old coolant sensor (or new one, if thou art so inclined ... and wealthy).

Ta-daaaa! One less annoying thing to get in your way, and three fewer hoses to deal with!

Here's a pretty pic for those wishing to see the finished product...

 

[9350coupe]

did mine the same way! works well......