Reliability of MTC Heater Valve Core?

[jhh925]

I'm wondering about part #11 in this RealOEM diagram (BMW PN 64118390132):



I've replaced my heater valve core with a brand new MTC valve core once, and it lasted maybe 2 weeks before essentially the same symptoms returned (regardless of where the thermostat setting is, I get heat at idle and zero hear once the engine is under load and the car is at speed). I haven't opened my heater valve up again yet, but I'm assuming the diaphragm is torn again.

Is the MTC stuff really this unreliable? Is it worth ponying up for an original BMW part? (The cheapest I'm seeing for OEM is about $142 vs $16 for the MTC valve core at AutohauseAZ.) Any other suggestions?

[tn535i]

When I started reading I expected Months or Years to follow the 2, NOT Weeks, that's really bad. But yes they are no where near the quality of the original which should last 20 Years or more.

If you are buying and MTC kit I always suggest get 2.

If you search you'll see several have found ways to adapt less expensive but more reliable alternative valves from other cars. It might be what you want to consider.

[jhh925]

Thanks, tn. After your reply, I thought I'd try to find some of those posts about the more reliable alternative valves. I searched on "heater valve" here, but didn't seem to find solutions other than core replacement. What should I be searching on?

However, I did find a post on an MB forum from back in 2015 comparing the MTC part to the Bosch branded version and the BMW OEM version. Here's a link. Interesting read. The short version is that they guy found that the rubber diaphragm on the MTC valves tended to have a larger OD, and therefore didn't seat correctly in the valve body. He suggested taking the time to make sure that the diaphram seats in (by forcing it?) when you install the new part, but I'm under the impression that the solenoid moves that diaphragm up & down, so just seating it once on installation doesn't take care of the issue?

Anyhow, I found a German source that sells the original BMW part for about $110 (and I need a couple other items from them anyhow), so I may just end up buying OEM.

[camplo]

I replaced mine with a e46 one for dirt cheap. It was a used unit that came with the harness from ebay. It does need a couple of hoses to make it work but it works great.

[BRRV]

Thanks, tn. After your reply, I thought I'd try to find some of those posts about the more reliable alternative valves. I searched on "heater valve" here, but didn't seem to find solutions other than core replacement. What should I be searching on?

However, I did find a post on an MB forum from back in 2015 comparing the MTC part to the Bosch branded version and the BMW OEM version. Here's a link. Interesting read. The short version is that they guy found that the rubber diaphragm on the MTC valves tended to have a larger OD, and therefore didn't seat correctly in the valve body.

YES. I have three of them, none of them work, none of them fit properly. Perhaps it's a valve body issue, as someone suggested to me, but I have three different valve bodies and none of them work in any of the valves. They all leak from the weep holes, and all of them lose the ability to give heat except at idle. Bite the bullet and buy it from BMW, because unless you can find a used Bosch insert (which I finally did) you're just chasing your tail.

Do not waste money on that POS insert until MTC decides to fix it, not likely I'm afraid.. (The Ferrari guys use the same insert; so does M-B, and those guys are livid, too)

I chronicled my problems with this here a couple of years ago on http://www.mye28.com/viewtopic.php?f=3&t=121283

[John in VA]

If you plan to use the MTC (or another brand, for that matter) insert, get it from FCPEuro.com, where it comes with their lifetime replacement.

[Eta power]

I bought one and ruined my old heater valve. I paid through the nose for a new one from BMW and no more heater valve problems after that. Sometimes, if you want it to work, you just gotta pay...

[BRRV]

If you plan to use the MTC (or another brand, for that matter) insert, get it from FCPEuro.com, where it comes with their lifetime replacement.

...so that every time you go through the charade of replacing the MTC insert and discovering it doesn't work either, you can have them ship another worthless insert and then ship the previous worthless insert .. back.

Been there. Wayne (PP) and I had a long exchange about this part, and it never was satisfactorily resolved (I still have the non-functioning parts, too). His warehouse manager swore up and down it was me or my valve, in spite of careful and detailed information that it simply wasn't the same part; their answer was "well we sell a ton of 'em and we never get 'em back.."

Side by side, there are noticeable differences between the original Bosch insert and the MTC fake-copy. Members of the M-B forums who have been dealing with this (and they all agree the MTC doesn't work and can prove it) have actually looked closely at the MTC part as well as the now-discontinued Bosch part, compared them to the BMW insert, and it was actually a win for the BMW insert: it is different - extra washer, thicker rubber, an improvement over the Bosch replacement. And they were looking for a replacement for the "pricey" M-B insert..

I won't speak for or against FCPEuro, since I don't use them (long story - right up there with RockAuto). Bottom line: so long as MTC represents the only aftermarket option, buy an original from BMW - maybe they'll continue to stock units that are correct. If not, there's always the M-B insert for their monovalve, which is allegedly the same part. Yes, it's highway robbery (the cheapest I've found it is Blunttech; about $145). You could try a gen-u-ine M-B part from ECS Tuning (ES# 2517529); various M-Bs use the very same valve - I already have one on order to test...

M-B valve shipped on 7/21... UPDATE: Received the mono-valve insert, genuine M-B part in an M-B box, sourced from an M-B dealer. This valve insert is literally identical, appearance-wise, to what we are used to with Bosch or BMW-sourced inserts; it appears to be the real deal. It's noticeably different from the MTC faux-insert being sold. I see no reason, none, why this won't work. I'll test it as time permits, but comparing it to a non-working but intact original BMW insert, even the rubber markings on the diaphragm edge are identical (look at it under a loupe and you'll see what I mean!). I have pictures which I've archived and may post at some point...

[demetk]

I documented my e46 valve install here: http://www.mye28.com/viewtopic.php?f=3& ... 6#p1400994

[Mike W.]

Years ago I got one, Bosch I think it was but I'm not sure, and the coil was apparently dead, out of the box, all heat, all the time. So I swapped the new rubber to the old part and it was fine for a few years.

Moral of the story: Don't throw out the old parts at least for a while. Mix and match may be as good as it gets.

[BRRV]

One of the guys on the M-B forums actually dissected both an MTC valve insert (documenting everything that was different about it in the process) and a Bosch valve insert, and then rebuilt the MTC valve insert with parts from the Bosch, and it worked, apparently. Made my head hurt just thinking about it.

[travisj]

Years ago I got one, Bosch I think it was but I'm not sure, and the coil was apparently dead, out of the box, all heat, all the time. So I swapped the new rubber to the old part and it was fine for a few years.

Moral of the story: Don't throw out the old parts at least for a while. Mix and match may be as good as it gets.

My MTC replacement was shite, so this is the route I took and it is holding up great. Frankenvalve is the way to go!