TB coolant plate bypass a success!

[BrandC]

Okay folks, let me start by apologizing for no pics! I was exploring the M42 during my oil change. I decided to yank off the TB and manifold and encountered the grizzly mess of coolant hoses near the TB. Like everyone has been suggesting to do, I got rid of them. It's very simple.

The hardest part is getting the throttle body off at an angle from the two coolant plates. There is one between the TB/Intake Mani and one underneath. I should tell you it requires a bit of tact removing the TB.

To remove the TB I had to seperate the tiny coolant hose from the larger coolant plate to the smaller plate underneath the TB. You will lose a little bit of coolant. After you have gotten off the TB successfully, it's all downhill.

1. Remove TB but keep it in the engine bay. No use seperating it from the cable unless you want to clean it.
2. Remove upper intake manifold and set aside.
3. Remove 2 brackets that hold the lower manifold still and adjacent nuts/bolts.
4. Take off the ICV (clean it while you're in there!)
5. Locate the two larger hoses that connect to both coolant plates and seperate the plates from them.
6. Remove the hose coming FROM the cylinder head and hose from the lower coolant plate.

Now here's where people might think it's ghetto. I bought a 3/8" brass barbed union thinking I could just join the two coolant hoses, but I found they were too long and the hoses would be bent at an awkward angle. So what I did was just cut a 4-5" piece off of the coolant hose (cylinder head hose) and used that to loop it. Fits great!

I took part #12 (cylinder head hose) and cut it. I used this to do the bypass.

http://realoem.com/bmw/showparts.do?model=AF93&mospid=47305&btnr=11_1272&hg=11&fg=35

There are probably no performance gains doing this delete. However it makes it TONS easier to remove/install your manifold and TB. I am glad I did it and hope people are adventurous enough to try it too! LMK if you have questions. Cheers and happy motoring!

Edit: I will try to get some pics cuz I know u are all pic whores.

[magnum2066]

Edit: I will try to get some pics cuz I know u are all pic whores.

You are my hero.

Great write up!

[e9nine]

FYI when you shorten/adjust/modify/lengthen a rubber hose that is molded to have a bend, make sure you wrap it.
I did my delete this same way the very first time and the hose didn't like to be stretched as you could see stress marks even. It only lasted about a day and I figured I would wrap it up to "preserve" the new form. There's a product out there in auto-stores just for this purpose. I have forgotten the exact name but it basically works by "bonding" itself to the rubber hose and it STAYS on it. I have used it several times and it has never failed me.
I'll try look for the name of the tape.

This doesn't apply to all methods. This is only when you modify the hose and notice that it's now straight and not curved like it was made to be.

I know this may sound complicated - but it really isn't. Once you're in the process of doing this - it's self explanatory. :cool:

[BrandC]

FYI when you shorten/adjust/modify/lengthen a rubber hose that is molded to have a bend, make sure you wrap it.
I did my delete this same way the very first time and the hose didn't like to be stretched as you could see stress marks even. It only lasted about a day and I figured I would wrap it up to "preserve" the new form.

e9nine: I know exactly what you mean. This is what made me weary of doing the delete with a stock hose at first. However, to eliminate the stress of "unnatural" bending I chose the straightest section of hose I could that was 4-5" inches.

Anyway, PLEASE let me know what the name of that tape is so I do not need to buy a new hose lol. I might just go looking for a new hose just to be safe.

[e9nine]

Dude I can't remember for the life of me where I bought the tape from. The reel I have left is not labeled so that's of no help. I'll update the thread when I find out.

A trip to autozone/PepBoys/NAPA and a visit in the section with sealants should yield a similar product. It's a 2 ply tape with the actual used section separating from the non-sticky section. It bonds nicely once the hoses are heated up and is virtually tight. The non-sticky section looks like regular Sellotape/Scotch tape.

[highlandmiata]

self-vulcanizing tape. 3m makes some. mcmaster part #    
7643A71

[e9nine]

self-vulcanizing tape. 3m makes some. mcmaster part #    
7643A71

This fits the description perfectly!

Thanks dude!

[silverblades181]

This is great for south states...but those of us in the snow belt need that coolant passage. I hope people realise that. If you bypass it, condensation will freeze your throttle body during winter.

[AL GReeNeRy]

gotta problem...

i did this bypass recently and rerouted the intake lines.  when i did this, i rerouted hose number 18 straight to the block. the car ran fine till i hit a bump and i guess the hose flexed and busted (stupid of me to try to reroute a 16 year old coolant hose).  when it busted, i was at a gas station and immediately added water.  i then drove a couple blocks to a relatives house and parked.  since then, ive replaced the bypass hose, but the car overheats with about 10-15 minutes of driving.  the check engine light popped up twice on me when the engine got REALLY hot.  upon further inspection, i found that neither of the heater core hoses are receiving coolant as well as the radiator and lower radiator hose(they stay cold or warm at most).  the upper radiator hose and bypass hose get BURNING hot.  i figured it was the thermostat and replaced the thermostat with proper gaskets and a new radiator cap.  after doing so, the car doesnt reach the check engine point, but it gets pretty hot..  the temp gauge jumps up to the red zone then drops to right before it and stays there...

i have a couple guesses: either the water pump is bad or i cracked my head gasket..

does anyone know what to do?

[e9nine]

This is great for south states...but those of us in the snow belt need that coolant passage. I hope people realise that. If you bypass it, condensation will freeze your throttle body during winter.

All of these are optional and not power gains. I like to simplify my car considering the fact I auto-x and do HPDEs and eliminate areas that can cause potential grief.
When I was in NJ, I deleted my TB lines on my 325i and never experienced any ill effects. However, just like many other mods - YMMV.

gotta problem...

i did this bypass recently and rerouted the intake lines.  when i did this, i rerouted hose number 18 straight to the block. the car ran fine till i hit a bump and i guess the hose flexed and busted (stupid of me to try to reroute a 16 year old coolant hose).  when it busted, i was at a gas station and immediately added water.  i then drove a couple blocks to a relatives house and parked.  since then, ive replaced the bypass hose, but the car overheats with about 10-15 minutes of driving.  the check engine light popped up twice on me when the engine got REALLY hot.

Bypasses like this when not done right can be catastrophic. Not calling you out on this but this was plain user error as hitting a bump should NOT cause such failure.
I'd suggest doing this the right way once and for all by fixing the hose and bleeding the system. You mention the car isn't behaving right but you've not indicated if you're trying to limp home or if you've replaced the ruptured hose.
Replace the hose, fill the car with coolant, bleed the system and then report back.

[2002maniac]

he said he did replace the hose.

My money is on an air bubble in the system.  Bleed it again and again

[D. Clay]

My bleed screw doesn't work anymore. The threaded plastic boss on the radiator split and I repaired it with epoxy and put a little clamp around it. It doesn't come out now so I bleed it with the upper hose. I take it loose at the top of the radiator and hold it straight up higher than the radiator inlet. When I see the coolant come up to that point, I stick it on real quick. I spill a little bit but the mess is cheaper than a new radiator.

[peaveybassist]

Take the radiator cap off, rev it up to around 2-3k. After you get good heat in the car, keep filling up the resevoir till its full. While its still revved up, put the cap back on tight. Should be good to go.

Will

[AL GReeNeRy]

i did replace the hose and ive FLUSHED the system a couple times already (you kinda have to in order to replace the thermostat).  but the problem has been isolated, at least i hope.. it runs fine now, but still runs warm - about half way on the gauge.  the top right portion of my radiator stays cold, right where the ect is.  the rest of the radiator is fine and the engine runs normally now.  i believe i ruptured a passage inside the radiator with one of those nylon zip-tie like things that hold in my electric fan.  i will be replacing the radiator soon.

[ecpreston]

This is great for south states...but those of us in the snow belt need that coolant passage. I hope people realise that. If you bypass it, condensation will freeze your throttle body during winter.

Just another data point: While I might not recommend it for everyone, I deleted it on both my m10 318 and my E36 325 and never had problems with VA winters, with temps well below freezing. I don't know at what temp TB icing is really a problem, but it must be pretty darn low. Heck, many cars don't even have coolant passing through the TB, makes me think it might just be a German overengineering thing. They wanted to make sure you could drive in Greenland or something. :p