310IROCZ

iTrader: (1)

Can someone please post a picture of there TPI TB bypass and also a pics of a bypassed heater core. thanks

Iroc_youroll

There is nothing to really look at.

Bypassing the heater core is as simple as removing the two hoses going into the heater core, and connecting them to one another. A simple connector and two hose clamps are all thats needed.

310IROCZ

iTrader: (1)

cool thanks, I just cut it all and ran a line from the TB to the oveflow on the radiator. looking at it not even sure if i need that. can i just block it at TB?

OneLethal87GN

Exactly which 2 hoses are the ones going to the heater core? I believe I see them but wanna be sure. Can you just plug the hole in the radiator and kill the heater core and t.b. issue at the same time? Thanks.

cameron7710

the heater core hoses r the 2 next to each other at on the passenger side firewall

Iroc_youroll

The two hoses going into the heater core can be found coming from the radiator into the heater core inlets on the passenger side of the firewall. It is located between the heater blower motor and the passenger side of the engine. Very easy to spot.

As far as the TB, i have no information.

Plugging at the radiator is efficient i suppose, but i kept my hoses and just connected them.

uemf

I don't think plugging it at the radiator is a good idea.
on my 'bird, it functions as a bypass around the t-stat... of coarse most of the guts were ripped out. I basicly have a line running from the water pump to the heater core, then from there to the radiator (the PO installed a ball valve to cut down the flow while adding water).
I could be wrong, maybe the ... valve ...that was origionally on the car doesn't act like a bypass... of coarse , I live in south Texas, the more coolant flow the better !
I'd say run a hose from the water pump to the radiator, if you want to bypass the heater core, is your safest bet.

Tony

Chrisry1995

iTrader: (1)

I just answered this question for a guy. https://www.thirdgen.org/forums/atta...heaterhose.gif
Run the hose from to top/front/center of motor "waterpump-hose" right to the radiator where hose #7 connects to. You can use a heatercore **** if you want. Don't connect to overflow. The water pump hose connects to the thottle body, then come out the side of TB then goes to heatercore,comes back out and into the radiator. Radiator has 2 BIG hose on each corner diag. and 1 small 3/4' or so hose. That's where you need to connect to. Picture should help.

Luda92RS

ill grab a pick of my heatercore bypass in the morning, pretty simple, although its kinda a bitch to get to on my TBI motor, and its run like **** ever since, although i doubt its the heater core bypass itself, something else most of gotten messed up.

Chrisry1995

iTrader: (1)

Your first post say's you have tune port injection like the diagram I gave link to. Search for " I have coolant coming out of mt throttle body... help???" That's where I got link. The last post you made say throttle body injection TBI. Which do you have. That post should help out if you indeed have TPI. Read the post and it explains exactly how to bypass with Diagram. Good luck. You shouldn't even have to get to the heater core lines. Just run a hose from manifold to the radiator, NOT THE OVERFLOW !!!

Jasper45

Hey guys I bought a 92 Z28 5.0 TPI converted to 5.7 TPI that's having overheating problems and I've gone through everything but I noticed the previous owner has a hose going from the throttle body fitting arched down to the intake manifold fitting and has plugged the threads at the water pump why would he do that? and would that cause overheating?

Chrisry1995

iTrader: (1)

Does your water pump only have 1 place for the big lower radiator hose?http://www.edgesz28.com/edgesz28/sub...ccessories.htm has some pictures of a TPI conversion. You water pump shouldn't have any threaded plugs or if they are, should be O.K. Not sure how 92 block is set-up, but my 89' should be close... Also look at above post where I gave link to hose routing. Is that what your motor looks like? I think you need to have the manifold fitting going to atleast the radiator, "if you want to bypass thottlebody/heatercore" for proper coolant circulation. Don't forget to check for an airdam on the bottom of radiator. Needs to scoop air from bottom of car towards and into radiator. This is a MUST!!!!! Let me know what you have and if you need anymore info.

Jasper45

The plug you see in the top pic of that waterpump is where I was sayin mine is also plugged but I didn't know if one of those fittings from either the intake man. or throttle body was originaly supposed to be goin to the pump it just doesn't look right the way the hose is arched. But you say one should go to the radiator? should I take a picture and show you how it's connected? I just put a new air dam on too this is the only thing that doesn't seem right

Chrisry1995

iTrader: (1)

Did you look at the https://www.thirdgen.org/forums/atta...heaterhose.gif This shows the hose coming from pass side of throttle body to heatercore to radiator. You should have a molded hose with a curve that goes from the manifold to the driver side inlet of throttle body. You need the molded hose. Or you can bypass the throttle body and hook to heater core or the radiator. The gif. above should show all you need. The water is coming out of the manifold, goes to driver side TB inlet, then out of pass. side and then the gif. shows the rest. If you need, send a pix. But the above info should be self explainitory. Let me know if you need more.

Jasper45

I have the setup on the left and it's all there but I also have a fitting on the front bottom of my throttle body and thats the one that has a hose going directly beneath it to the intake manifold fitting. I have read somewhere the tpi systems have coolant run through them to keep from freezing in cold temps do ya think thats what its for? Should I take a pic?

Chrisry1995

iTrader: (1)

YEAH,YEAH, YEAH, That's it!!!!! That goes through the throttle body just like you said to help with winter operation. So then you have all the rest hooked up like the picture then? You have exactly what I have then. You can hookup the hose from the manifold that youv'e been talking about and connect it where hose #3 goes in the diagram. To the black vacum/valve. That will bypass the throttlebody. I disconnected mine last summer but didn't notice any difference. I reconnected for the winter and will leave it. Some guys bypass because a colder tb will give a dense air input, but I think by the time it gets into the plenum, down the runners and finally to combustion chamber, it don't make that much of a difference. I did the cold air intake stuff also. The only time you'll see a help is when you race 1/4 mile and your only talking way less than a 10th off your time. You'll never notice with street driving. It's just 1 of those things you do with a bunch of other little things like an air foil for TB that will add just a smidge of extra omph....

Jasper45

OK maybe I'll just get the RIGHT molded hose so it won't kink and that will help the coolant circulation. Thanks for your help! The way he had that hose routed it didn't look right but it makes sense now.

Chrisry1995

iTrader: (1)

Cool. Glad to help!!!! You can also start your car and let it warm up with the radiator cap off. When it gets around 160-180, you should see the coolant flowing BIG Time!!! As you give it gas, that coolant should have all kinds of flow. If not, flush radiator. Also make sure the waterpump is turning opposite of all the other pulley's. You can also check that the fan is coming on. Some have 2 fans, like mine. These cars don't kick the fan on until 210 or so. That's too hot. I put an adjustable fan switch that hooks up with a temp. probe to the lower rad. hose, and I can adjust what temp I want the fan to kick on. I wired the 2nd fan with the wire that goes to the sensor. I hooked up that wire to one side of switch and the other side, I ran a wire to ground. The temperature sensor is on the pass. side of the block, just below cyclinder #6. If you only have 1 fan, you can still hook it up, just not sure if it's the same sensor. You could also use the air conditioning switch that comes on when air is on. It's on the silver lines going to the front of car. Just tie the switch into that because when the air is on, that switch shorts the 2 wires and forces the 2nd fan on. I did that for awhile too.Some guys tie the 2 fans together so they both come on at same time. I just left the 1st fan alone and hooked-up the 2nd. I never have a cooling problem ever. There is alot if info on the fan situation posted. I got my adjustable from Pep Boy's for under $20.00. You can also just buy a sensor that turns on sooner, 180 deg. for about $35.00 from Summitracing.com. Stock, these cars run just too hot!! It's nice to be able to kick the fans on when I'm in a traffic back-up. Good luck. Let me know if you need any other help. Glad to do it.

GMan 3MT

iTrader: (4)

No sense adding a new thread sooo....

My motor is a '92 TPI setup, and I'ld like to do the tb bypass, get rid of the diverter, heater core and blower yet still retain my stock oil cooler. Can this be done?

My understanding it that I would have to cap off the nipple at the intake, plug the inlet and outlet of the tb (just to keep debris out of it). Question is, what can I do about the cooler lines? One goes to the radiator, where could I tie the other end to?

TheScaryOne

iTrader: (3)

Run the hose out of your intake, to the inlet side of your oil cooler. Because of angles and belts this is easier said than done, but you'll figure it out. Leave the return line for the oil cooler in place, as it returns coolant to the radiator.

LAFireboyd

iTrader: (3)

You said you returned it to the overflow on the radiator, but I suspect you meant to the heater hose return nipple, just below the overflow nipple.

You asked your question 2 months ago, so I'll guess you've found the answer. But yes, you can just block it at the TB(actually, at the manifold to bypass the TB, because you haven't yet bypassed the TB). Then with having removed all the heater hoses and valve, bypassing the heater completely, and bypassing the TB, you're correct, you won't need any hose at all returning to that location on the radiator.

So now to bypass the TB, remove the U-shaped hose from the manifold to the TB and either cap the manifold nipple with a rubber cap, or remove the nipple from the manifold and plug the hole(like the water pump is plugged).

Then where the hose originally returned from the heater to the radiator(currently from your TB), just cap that radiator nipple with a rubber cap. In some radiators, that nipple is removeable. If yours is, then it would be better to remove it and plug the hole.

If you use the rubber caps, don't consider them to be permanent. They'll eventually deteriorate under the pressure and blow. So it's better to remove the nipples in both places(the manifold and the radiator, where possible), and plug the holes. But if you use the rubber caps, keep some extra ones in the car, just in case...

Chrisry1995

iTrader: (1)

Are you guys reading the posts and looking at the diagrams provided in above reply's? Everything should be in there. The only thing I recommend is NOT to plug the intake hose. The intake hose comes from the intake and goes to the radiator. THAT'S IT!!!!!. That hose is used to run water through the assesories. If you want to hook-up the heater core, then run it in-line. If you want to hook-up the throttle body, then do so. Oil cooler, samething, Everything is in-line like batteries in a flashlight.The motor must have a Radiator and the 2 big hoses connected to it so you have a water circulation system. The intake water port pushes alot of water also, and this returns to the radiator just below the Rad. Cap. You must keep these 3 hoses connected. The small hose is to cool/heat your assesories,heat core,oil cooler, throttlebody etc.....Please, try not to complicate the system. If you want to bypass or hook-up anything then just bypass or insert the item. EVERYTHING is in-line from the intake, to the radiator using the small hose. . IF you bypass something, you have to connect something inline or the water will come out. Please look at the links for pictures of your system. Also read what I replied to the others and follow exactly what I wrote with the diagrams. I refer to the labled hoses and were they go. Once you look, Everything should be clear. If the links are not working, let me know.

LAFireboyd

iTrader: (3)

Easy there, Chris.

If someone has deleted, or wants to delete, all of the accessories, then the only needed circulation will be from the pump thru the block, to the radiator and back to the pump. Therefore, there's no need for a hose coming out of the intake, or any other "extra" hoses, for that matter. And that's what the original poster, to whom my post is responding, asked about doing.

Mine's been set-up, just as I described, for several years now.

What I described, however, isn't appropriate for most cars/owners. But for people in warm-weather states like CA and TX, where, not coincidently, I live and the original poster lives, where our cars aren't necessarily for daily-driving, or we don't feel the need to keep the heat, a/c, or any other cooled accessory intact, then it's fine to delete all of those hoses.

Deleting them eliminates several possible failure points in the cooling system(such as heater cores, bypass valves, and hose leaks), not to mention it makes for less "clutter" in the engine compartment.

Chrisry1995

iTrader: (1)

Yeah, your right. My bad Sorry!!!!. I see what your saying. If one is to live in a warm climate, does pluging the intake hose not cause a problem with cooling? I read that blocking that could cause cavitation in the water pump and it's best to leave connected if having heating problems. Also by running the hose direct from intake to radiator, you also have less chance of failure from plug blowing out because of the presure behind it. What do you think?

LAFireboyd

iTrader: (3)

Being a t-top guy, I rarely used the a/c. And living in SoCal, I rarely used the heater either. So when each failed(the a/c needing recharging/changing-over, the heater core leaking), I decided to eliminate them, rather than keep/fix them. And my car never had an oil cooler(not yet available in 1987, IIRC). So when I bypassed the TB, I saw the chance to delete all of those hoses, and the cooling system has been more efficient than it's ever been.

A pipe plug in place of the nipple in the front of the intake(where it exits at the U-shaped hose that went up to the TB) won't blow out, but those rubber caps(clamped onto the nipple) will blow out. The rubber caps are supposed to be able to handle the pressure, and they can... for awhile, but not for the longterm. That's why I recommend using plugs, if this is done.

Unfortunately, the heater hose return nipple in my radiator is plastic, molded into the radiator tank. It's not the bolt-in type, so I can't remove it. It's clamped with a rubber cap, so I have to visually inspect and change it from time-to-time.

sapper

Chrisry1995 Thank you a lot your diagram provided me with the info i needed (could not find in haynes man) . I just bought a 92 rs and heater core was leaking took it out and found 1 hose pluged with a spark plug and heater bypass just gone (not there) had a problem wrapping my head around that one. Also the vaccum hose was plugged with a glass fuse . All that trouble just to bypass a 16 dollar part hmmm looks like i have some more work to do thanks again everyone this thread has been most helpfull.

panhead201

I just happened to see this thread cause I've developed a vacuum leak behind heater control mod on dash,,but I'm not sure some guys know the difference between a tbi and a tpi.Thats a tuned port injection in the diagram.Tbi,s look like a 2barrel carb under a regular old air cleaner and are different.The tbi,s have a return inlet at the top of the radeiator,pass.side,3/4 hose.panhead