Proper cooling system bypassing + res relocation

[static]

Hi, more questions

here is how my cooling system is routed currently (sans the rad hoses)


as you can see, the TB and heater core are bypassed (not needed). My question is: is there a better way to route the cooling passages to maximize the cooling capability? (like for instance, do i really need to bypass where the heater was, or it's better to just plug the hoses. Same for TB hoses.)

my other question was would it be a good idea to relocate the coolant res and run the hose not around the whole engine bay (like some people do, but under the harness cover, over and behind the back of the valve cover, beside the wires and perhaps wrap it in some thermo insulation)

Thanks a bunch
Alex

[matt]

Run the coolant reservior right into the back of the timing cover and block the heater port on the back of the head. You may have issues bleeding the system, but jacking up the front of the car or parking on a hill will help.

[static]

Run the coolant reservior right into the back of the timing cover and block the heater port on the back of the head. You may have issues bleeding the system, but jacking up the front of the car or parking on a hill will help.

Thanks Matt. By the back of the timing cover do you mean the front-most barb on the head in my diagram? I can probably use some kind of manual valve to block it off with so i can manually bypass it while bleeding.

What to do with the TB hoses? block them off too? (smaller middle barb on the head)

What the hell is that metal valve that's connected to the rear-most head barb and one of the the heater core pipes on the other side?

[FredK]

What the hell is that metal valve that's connected to the rear-most head barb and one of the the heater core pipes on the other side?

That's the heater core bypass valve, which was installed as part of a still active recall campaign. The recall installed a bypass valve to avoid having the heater core blow up and puke hot coolant all over your leg.

[So Live]

So im running a temp sender like the TRM one where it gets installed where the TB heater hose went to the head. What should i do with the other heater hose (from the tb to the spider hose)? As of right now i just have a bolt w/ the threads cut off and a bead welded around it so it wont come out of the hose too easy. Sound good?

Thanks!

[matt]

Thanks Matt. By the back of the timing cover do you mean the front-most barb on the head in my diagram? I can probably use some kind of manual valve to block it off with so i can manually bypass it while bleeding.

What to do with the TB hoses? block them off too? (smaller middle barb on the head)

What the hell is that metal valve that's connected to the rear-most head barb and one of the the heater core pipes on the other side?

Well... you might be confusing the timing cover, where the front of the spider hose actually connects, with the head. It's the 3/4" or so barb pointing parallel to the crank straight back from the front of the motor. Next to the oil filter housing.

If you run the reservoir straight to that, you will not need the spider hose or any of the TB hoses (block the port in the head or install one of my temp senders)

So im running a temp sender like the TRM one where it gets installed where the TB heater hose went to the head. What should i do with the other heater hose (from the tb to the spider hose)? As of right now i just have a bolt w/ the threads cut off and a bead welded around it so it wont come out of the hose too easy. Sound good?

Thanks!

If you're keeping the spider hose, that's about the best you can do.

[static]

Well... you might be confusing the timing cover, where the front of the spider hose actually connects, with the head. It's the 3/4" or so barb pointing parallel to the crank straight back from the front of the motor. Next to the oil filter housing.

If you run the reservoir straight to that, you will not need the spider hose or any of the TB hoses (block the port in the head or install one of my temp senders)

Thanks again, so you're saying that it is totally safe to block off the TB hoses, right?
I figured that it should be the most efficient use of the flow generated by water pump to block off (as opposed to bypass) all those auxiliary coolant ports.
If i get rid of the spider hose, what do i do with the rear-most nipple on the head that feeds coolant to the heater core? Can i block it off too? If so, what's the best way to block it? (it's rather large diameter to block off with a bolt)

Fred: I noticed that valve has inlet/outlet of large dia and another barb which is i guess to route the excess coolant if the heater side of things is under too much pressure?

Cheers
Alex

[matt]

Make a plate to bolt to the head to block off the rear heater feed on the head.

Yes, it's safe to block the TB heaters.

It's pretty common to block all this off... it's the same thing that happens when your heater core is closed.

[So Live]

any pics of a motor w/o spider hose? I need to keep my heat though :(

[static]

any pics of a motor w/o spider hose? I need to keep my heat though :(

if you need heat, you still need to return the coolant flow from the heater somewhere. You can use a T in place of where spider hose splits into 4.


I did some more research on this blocking off rear of the head and here is an interesting thread with conflicting experiences of seemingly respectable members:

http://forums.bimmerforums.com/forum/showthread.php?t=825063&highlight=plug+heater+hose

perhaps the problems experienced by Chris (ceegeezM3) was improper bleeding (which may be hard with rear blocked as Matt suggested above)

I am coming to conclusion that the best sure-shot solution would be to put a manual valve in between of the rear head fitting and the return hose; open the valve while bleeding and keep it closed afterwards.

EDIT: ...OR, install some kind of bleeding screw solution into the blocking plate. Matt, do you guys fabricate these plates? couldn't find them on the website

[matt]

There is no way that issue was caused ONLY by blocking off the rear port... it must have been a bleeding issue or something else. When the heater valve is closed, there is no flow through that port whatsoever.

We are working on getting plates made for that hole, we do not have anything right now. When we do, they will NOT include any sort of bleed screw. It will not help to have a bleed there. They may have a port for a temp sensor though.

[turboeta]

Hurry up on that plate matt.

[static]

There is no way that issue was caused ONLY by blocking off the rear port... it must have been a bleeding issue or something else. When the heater valve is closed, there is no flow through that port whatsoever.

We are working on getting plates made for that hole, we do not have anything right now. When we do, they will NOT include any sort of bleed screw. It will not help to have a bleed there. They may have a port for a temp sensor though.

correct me if i am wrong, but isn't the whole point of turning the heater knob on full open while bleeding, is to bleed the air from the coolant passages in the back of the head? If i am right on this, wouldn't the bleeding screw on block off plate be a good idea?

Good to know TRM is coming up with one. Here is some competition intel for you:
TC Design block off plate with a 1/8" port for a temp sensor: $25 (comes with gasket and the screw-plug for the port)

[matt]

Thanks for the info... ours will be competitive.

The idea behind opening the heater core is to get the air out of the heater core, not out of the back of the head. The way to get the air out of the head is to lift the nose of the car and let the bubbles come out the T-stat.

[btec116]

(block the port in the head or install one of my temp senders)

Matt, can I have a little info on that temp sender? I have an M52 in a '89 318i. I need an engine temp solution (for my dash) that I can run straight into the C101 plug. The TB plumbing would be a convenient place for a sensor!
Thx.