Coolant/Heater hoses and a couple 530i-specific questions

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wkohler
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Coolant/Heater hoses and a couple 530i-specific questions

Post by wkohler »

In the middle of a bunch of work on the 530i. I found that both heater hoses are NLA, expansion tank hose is in Germany (have one coming) and the upper/lower hoses don't show available, so for the first time, I bought something made by ÜRO parts and frankly, I don't want to put that on my car.

I was curious if the 528i hoses (which all show available) will work on the 530i. All of my smog equipment is now removed (not a lot of fun) and from what I can tell, that must be the reason for the different hoses. It doesn't look like the radiator is different, Heater core inlet and outlet shouldn't have changed and the coolant pipe on the side of the block doesn't look different than the one on my M90 under the workbench, so I can't imagine there's much issue. The heater hoses were made out of sections of hose on my car, so using the old hoses isn't an option.

Also, could I just delete the coolant chamber under the throttle body? It's not a huge issue to leave it, but I don't see what purpose it serves. I'm already saving four miles of fuel hose by swapping to the later fuel rail but if I could just put a plug in the block, then I don't need it. I think the feed hose to that comes off the "Jules Verne device" so that would have to be capped off too, so I guess I could just leave it.
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Mike W.
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Post by Mike W. »

I'm almost positive the heater end is the same, the outlet off the back of the head is the same and the coolant pipe along the block seems to be the same, but they list 1 inlet and 3 outlet hoses. Makes no sense to me unless possibly they were routed around something that perhaps is no longer there. I put L jet off a 76 530 on an E3 and don't recall any issues with the heater return and the coolant pipe, although that was over 20 years ago now. :shock: On the water based AAV, I like them, I've never had a problem, although they seem to have a poor reputation here. So I'd be reluctant to do away with it. But there is no real need for the heat to the throttle body, they of course did away with that on E28s. So if you want to eliminate the TB warming I'd route the hose from the block to the AAV to the coolant pipe. And do use water hose there, fuel line will work, but it's not really rated for the same heat as water hose.

Availability surprises me, Realoem shows them with a price which usually means they're available, but I haven't checked. Autohausaz shows both parts (528i) available in CRP which I think is an arm of Conti, although they too may be made in China these days. Especially at the price I'd say go for it, the 528i parts. I can't imagine they'd be significantly different.
64211364770
CRP - Heater Hose; Coolant Pipe to Heater Core (Outlet)
1 per car.
$3.48
SALE$3.63
List: $15.32


64211364765
CRP - Heater Hose; Cylinder Head to Heater Core (Inlet)
1 per car.
$8.77
SALE$9.14
List: $14.08
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
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wkohler
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Post by wkohler »

Thanks Mike. I grabbed all of the numbers from RealOEM and checked with the dealer. The sheet isn't in front of me, but both heater hoses were NLA and so was the hose to the expansion tank, but shocker that my dealer actually had one in stock because it was returned to them three years ago from a local shop.

That's a good idea just bypassing the coolant chamber by running from the valve to the block. I didn't think of that. All of the hoses for that are currently fuel hose - and not very good fuel hose (Cohline). I was going to replace it with just the standard 8x13 hose, but I bet the hose from the radiator to the expansion tank would do well there, and think I will have just enough left after I trim the new one. Great news. I will cap the ports below the throttle body then. Thanks!
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Robert Bondi
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Post by Robert Bondi »

A few things to add:

1. The two formed heater hoses that go to the firewall should be the
same between 530i and 528i.
2. The coolant return pipe is slightly different between 77 530i and 80-81 528i. Only different is the little barb location. On the 528i, it points up and a ?-marked shaped hose connects up to the coolant chamber on the TB. On the 530i, that barb points out horizontally toward the driver side for hose routing to the water-based AAV. This detail made my table in the lambda conversion FAQ.
3. Realoem seems to be behind when gauging availability. When sourcing parts from anyone connected with BMW Mobile Tradition, it's become quite common place to be charged for a bunch of parts, wait a week, and then end up with a sizeable refund and a new headache once Germany informs the residents of North America of what they really have left. For example, the flywheel (11221270286) looks available on realoem. BMW kicked that back as NLA on my first attempt. :-(

Robert
Robert
77 530i
77 Euro 528
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Pierre
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Post by Pierre »

URO quality is actually pretty good. They have issues with fitment on some items such as windshield gaskets but hoses have wider tolerances and work well. I have had good luck with CRP hoses too.
If you bypass the TB coolant passage, bypass it, and do not block the two ends. You need to let the colant flow through. And you car will become undrivable under very cold conditions. (below 20 degrees) But again, who drives an E12 when it's very cold out?
Do NOT use fuel hose for coolant lines or vice versa. It's the composition of the rubber that differs. Fuel will chemically break down coolant lines from the inside out and coolant temperatures will crack and destroy fuel lines. And never use vacuum lines for anything but vacuum purposes.
Pierre in Camarillo
76 530i (3.3), 69 2002 (M20), 74 tii, 75 2002, 79 323i, 84 733i, 84 323i (S52), 91 318is, 96 318ti (S52), 97 Z3, 01 540i, 02 330i, 02 1150RTP.
OO==00==OO
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wkohler
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Post by wkohler »

Those coolant lines currently have pretty poor fuel hose on them and I was pretty surprised by that, but would have likely replaced them with the same so glad that was mentioned.

Three years ago, I paid $50 to have a radiator rodded out. Was quoted $165 on Thursday so that won't happen. From what I can tell, it looks pretty clean in there though I will flush it thoroughly and just roll with it.
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wkohler
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Post by wkohler »

I purchased hoses for a 528i and everything fit fine. The lower hose is the same, but everything else is different, and it's definitely because of the EGR. Now that my car is EGR-free, it worked out great. I capped the ports on the coolant chamber for the throttle body and then used the leftover pieces I have saved from radiator to coolant tank hoses and had plenty to go from the coolant pipe to the idle valve to the return port on the block. That was all done with fuel hose before.
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dsw99a
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coolant hoses delete

Post by dsw99a »

Hello Kohler, been following you on the forums for years. I am attempting to delete my coolant hoses. can u pm me for some specifice questions. i am thinking of deleting the egr also. having problems with vacuum i think. i capped off the large hose going to the cold start valve? should i? if not where should it go. i took of the aux air valve and the temp time switch housing. confused! let me know?
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maybeillbuyit
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Location: Vancouver BC

Post by maybeillbuyit »

Whew ,i just read this post though and it answered most everything I was wondering about. Now I just hope the 528i hoses are still available. After removing my EGR crap I was amazed at how many hoses there were under the intake bananas. Thx Mike, Chris and Robert
1977 530i another project
1979 635csi Euro "project"
1987 635csi
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