Heater By-Pass for the CS stock version

deQuincey

Quousque tandem...?
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you might remember what was done by thehackmechanic for CSI coupes in order to reduce the cabin temperature by closing the flow of coolant through the inner radiator and diverting it to bypass the heater:

http://www.e9coupe.com/forum/showthread.php?t=10824&highlight=heater+bypass


but this sound solution can not be implemented in the stock CS cars due to lack of space

two weeks working in scandinavian countries is providing me with enough flights to think-draw-design a solution, i might say that i am close to solving this problem

i still have to prepare a prototype first but,...
 
Hope your solution bypasses coolant through a Bialetti Moka Express coffee maker inside the cabin.

I can help test the prototype.

If your flights were to India instead you could solve even bigger problems. That may the problem with POTUS, his flights are too short.
 
DQ,

I am certain more than a few members of the forum will be waiting on your solution. Keep on drawing ...
 
Might be worth collecting our points and sending DeQ on a longer voyage!

hmmm ... i can probably help with that. sitting on 250k miles on sky alliance and another 100k on star alliance. will pick up another 75k miles on the next trip to qatar, and probably will go 3 or 4 more times this year ... and at least that amount next year. did i mention that i am really tired of flying.
 
miles are welcome, the POTUS is waiting for DQ

...there is always some plumbing that can be done,...:D

seriously, i will keep you posted on the topic, i will involve a couple of electric valves (automotive spec.) to build the bypass using the space available, two relais, a fuse and a 6 pin period correct switch, a plate and two lights red for heater ON = Winter, Green for BYPASS mode = summer

if i succeed it will be not only functional but beautiful too, at least i will try to

ancient phillosopher ARDEnius said once: "dont sell the skin before killing the bear"
 
hmmm ... i can probably help with that. sitting on 250k miles on sky alliance and another 100k on star alliance. will pick up another 75k miles on the next trip to qatar, and probably will go 3 or 4 more times this year ... and at least that amount next year. did i mention that i am really tired of flying.

I rolled over 1,000,000 lifetime miles with United (Continental) last year and have been 1k for the last three years. Yes, I understand being tired of flying too..

Yes! Waiting for the design too even though I have the faster CSi. Just interested
 
I rolled over 1,000,000 lifetime miles with United (Continental) last year and have been 1k for the last three years. Yes, I understand being tired of flying too..

Yes! Waiting for the design too even though I have the faster CSi. Just interested
yep, i'm approaching 2m on delta.
 
My $.02: Have only one light for the position you use least often, in my case it would be heater engaged, that way you don't have to look at the light on for 99% of the rest of the time. Only to remind you to turn it off when the weather warms back up again.

Otherwise, I have my popcorn and am looking forward to seeing this come to life :)
 
I too look forward to any and all DQ projects, having said that, I still feel a bypass is totally unnecessary... More so considering the complexity and clutter these systems are evolving into. Did BMW *ever* implement a bypass on any engine? It was always a shut-off. I will now take cover ;)
 
Luis, I have to agree. It gets pretty warm here in SoCal and I've never felt any heat coming from the heater box nor do I think I need a shield above the forward muffler.
 
I think he's referring to not needing to keep the flow going from the back of the head to the front and just using a valve to shut it off versus divert.

Another debate entirely :lol:

Luis, I have to agree. It gets pretty warm here in SoCal and I've never felt any heat coming from the heater box nor do I think I need a shield above the forward muffler.
 
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do we really need a bypass ?

well here are my thoughts:

i do not know if it is a real need of stopping the wáter passing through the heater radiator, i do not know how much heat would be refrained from entering the cabin if doing this, but it seems to me interesting to try, to keep a source of an average 85ºC beneath the dash is for sure not the best idea

it is not a priority, but i discovered pieces that might make this work conveniently, the process was:
1- i found the pieces
2- i started conceiving the solution

i would not consider bypassing permanently the tubes by linking them together as it was presented by a gentleman living in tropical climate ;-)

but absolutely i would not block the coolant flow as one fórum member did with the help of his mechanic that said "this is the way BMW would have done":shock:, did i mentioned before that i do not trust in average mechanics ? yeah, probably more that once,...:p, it is ok with them, but: 1st. they do not have the time 2nd.. the car is not their car, it is YOUR car, it is so easy to bet with someone else´s money...!

i need to be able to switch from one situation to the other, moreover i would prefer to run some coolant now and then through the heater radiator instead of keeping it fluidless and dry

on the other hand i prefer to drive knowing that the engine will not suffer, than being in the risk of blowing the head gasket, stories of 5th and 6th cylinder being badly refrigerated fill my nightmares

i know that younger M30 engines have a tap that simply closes the flow, but those engines are not conceived as the M30 carburetted versión, i can not tell the way the block, head, and so on is built, who can assure those engines are built the same ? who knows the differences of coolant routing ?

what is the effect of closing the hose that goes inside the admission manifold ? i am unable to tell if the coolant circulation through those admission manifolds is made to cool the manifolds or to warm the fuel mixture, so what would be the effect of blocking that part of the circuit ? temperature will increase there for sure,...

the switchable bypass is a very simple solution, the most important problem is the lack of space and the need to find automotive rated valves for a mínimum functional warranty

so i will go the route the real bmw would have done,...if complicate Works just as well why make it simple ?, ha, ha, ha

IMHO
 
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first idea

global sketch of the idea

two electric valves, normally open, they close if 12v is applied

this runs for safety if any failure happens they will remain open

the circuits will be fed by a signal coming from the fuse box only live if clausor is ON, a fuse and two relays will opérate the valves

a two position (two circuits) switch will be able to opérate both valves at the same time as one will be on and the other off

Winter time stands for circulation through the heater, a red light will be on, summer gives bypass and a Green light (i considered steve´s idea of only one light, but..., finally i prefer both lights)



sorry seems that the photo is upside down and i can not edit it to rotate....-(

comments ?
 
I no longer resemble this remark ;-)

I have the Hackmechanic bypass on mine, albeit plumbed to accomodate the side drafts as added to this thread:

http://www.e9coupe.com/forum/showthread.php?t=10824

I am in the camp of not chancing interrupting the flow from these early heads. Especially here in the tropics. :smile:


i would not consider bypassing permanently the tubes by linking them together as it was presented by a gentleman living in tropical climate ;-)
 
My $.02: Have only one light for the position you use least often, in my case it would be heater engaged, that way you don't have to look at the light on for 99% of the rest of the time. Only to remind you to turn it off when the weather warms back up again.

Otherwise, I have my popcorn and am looking forward to seeing this come to life :)

i have a green foglight switch that is not being used, and a hole in the '74 underdash panel (my car has a 74 telescoping steering column). that could be perfect for this exercise.
 
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