M52 heater hoses?

[Daeldalus]

Which hose do I need to go from the metal pipe to the heater core? The other hose us supposed to be the e30 hose, but obviously the e30 spider hose won't work for the other side.

So, do I need to use the 328i pipe to valve hose? Or is there a better option for it?

I tried looking on here for previous threads but they were all for m50s and say the use the e36 spider hose.

[mtech325]

If you want to use the OBD1 style spider hose, here's an option for the pipe adapter:

coolant pipe adapter

I've used it with success on my s52 with both the m50 spider hose, and later with the m20 spider hose (since it deletes the throttle body warm up and is a single piece hose all the way into the m20 style expansion tank).

If you want to save a couple bucks, you can do the same thing with the OBD2 coolant pipe by chopping it and JB Welding it in place for use with the OBD1 hose.

[Daeldalus]

Really want to keep the m52 pipe since it is already in place. Just looking for a hose that works for it without any hassle.

[mjweimer]

Really want to keep the m52 pipe since it is already in place. Just looking for a hose that works for it without any hassle.

Daeldalus - in my notes I wrote down two part numbers for the heater hoses to work with my M52:

62 21 1 380 527 (from head to heater core inlet - E30 part)

11 53 1 703 844 (from metal pipe to heater core outlet - E36 part)

My swap has been paused for a bit due to other projects so I don't know how these will fit - no personal experience - but I took a ton of notes when planning my build and these will be what I order to try when the engine finally goes in the car. I imagine that these hoses might need trimmed a bit to fit but that should not be too hard.

Make sure to post back here to let us know what you find out.


MJ

[Daeldalus]

I have ordered both parts. We will see what happens

[mjweimer]

Good deal. I hope it works out and will be interested to hear the result.

[Daeldalus]

the m52 stock heater hose from the coolant pipe fits.

you have to bend the heater core outlets down for it to fit correctly though.

the problem I had was that I did not originally bend those down and the intake manifold rubbed a hole in the top of the hose.

[brads2002]

This topic is very helpful for me too. I have the engine out of the car and want to get this right before installing. I hear that the intake has to come off if its after the fact?


I am swapping an s52 into a 1991 318is. I have the metal line. Guessing its the same in all motors?


e30 hose from head to the bottom.
e36 hose from metal to the top.


Do these lines need to be trimmed and can you give me a rough idea of how far to bend?


I am planning to run 318is radiator with the expansion tank running to the middle of the metal hose. TB line has been capped.


From what I understand I can use one of the 318is radiator hoses and will need a euro 323 hose for the other 1720720 (looks like can be ordered from ebay from somewhere overseas).


Thoughts and thank you.

[Daeldalus]

Not sure on the radiator hoses since I used the late m20 radiator setup.
As for the heater hoses all the information you posted is correct as far as I know.

For the metal lines to the heater core they need to be bent down around 1/2 inch or maybe a little more. Just whatever amount is needed to clear the bottom of the intake.

[brads2002]

sweet, thanks for the help. I appreciate the confirmation