BMW E30 318i M10 heating system

[damers2000]

Hi All,

Trying to find out exactly what the coolant hose layout should look like in my pre-facelift E30. The previous owner had some kind of an issue and re-routed a hose to bypass something, be so much easier to compare one that is fully functioning.

I'm in Byram, neaar Knottingley \ Castleford, West Yorkshire.

Cheers

[ah]

Try putting up images of M10 318i and see what google comes up with.

[damers2000]

Try putting up images of M10 318i and see what google comes up with.

been there, done that mate but its not conclusive. The pipework I need to have a look at comes out of bulkhead and under the engine, or should do I think...... Bought a haynes manual in the hope that might help but, nope, no help at all

[ah]

Right ok, you need to get in contact with Brianmoooore,if he doesn’t know you have got real trouble.

[Satan]

Have you checked the WiKi and Realoem to get an idea?

[martauto]

Hi All,

Trying to find out exactly what the coolant hose layout should look like in my pre-facelift E30. The previous owner had some kind of an issue and re-routed a hose to bypass something, be so much easier to compare one that is fully functioning.

I'm in Byram, neaar Knottingley \ Castleford, West Yorkshire.

Cheers

Pop up some pics of what you are concerned about so we can see the problem areas.
My M10 has a webber on but it may not be the original water system.
Over in Morley by the way

Mart.

[damers2000]

Hi all,

Thankyou for your responses so far. I've attached photo's below to show the issue. As you can see, it seems to be the lower pipe coming out of the bulkhead which is bypassing something and connecting straight into the large hose at the front of the car. Ignore the filthy engine bay, currently being restored so hopefully look a bit better soon!

Also, if a visit to Morley would help and is same coolant layout, I'm more than happy to have a ride across.

Thanks again!

72537257_10157814378174515_4341478806813409280_o.jpg

71911497_10157812875479515_4796076905839198208_n.jpg

72269737_10157812875534515_5111465146182533120_n.jpg

[Satan]

Does your heater work in the car?

[damers2000]

I dont think it does blow hot air, I cant check at minute as it's in bodyshop

[Satan]

Was just wondering if the heater matrix was bypassed if that is at all possible, clutching at straws here as I am no expert.

[damers2000]

Was just wondering if the heater matrix was bypassed if that is at all possible, clutching at straws here as I am no expert.

really appreciate it mate, I've been looking through the history and came across a note which said customer advised of coolant leak, so I'm guessing that that was when the faulty item was bypassed. I have no experience of E30's so completely in the dark here

[Satan]

I don't have a clue either but throwing suggestions up in the air sometimes helps garner a response.

[Satan]

Also circle the areas you are concerned with in RED

[martauto]

Also circle the areas you are concerned with in RED

Plus one mate

Mart.

[martauto]

There seems to be a stack of jubilee clips joining .....Well not really sure
You are most welcome to have a look at mine ( ) but with mine being the webber it may not be "stock" but let me know if you fancy a trip?

Mart.

[BristolE30]

Looks almost definitely like a heater matrix bypass. Especially if it’s coming out the bulkhead. The only reason the cooling system goes into and out of the bulk head is for the heater matrix. Also confirmed by the fact you have no hot air.

Heater matrix bypass pretty common if having either a leak with matrix or problems with bleeding system and getting air trapped

[BristolE30]

Or potentially PO came up with a way for the hot coolant to get into heater matrix with more ease. Doesn’t really make sense that you have no hot air though

[Brianmoooore]

The flow and return pipes to the heater are on the bulkhead, one just above the other, just inboard of the brake servo.
Is there anything connected to these pipes? Are the pipes actually there?

[damers2000]

Thanks all very much for your help with this, when I get the car back I'll have a more thorough look at it.

The hose with all the jubilee clips is the one I am referring to, it's certainly not standard.

There are pipes going into the bulkhead, above and below each other near the brake cylinder.

[Satan]

Remember also the original clips need a special tool to fit them (I believe) so if any work was done then jubilee clips would be used as a replacement once they had been removed.

[Brianmoooore]

If there are connected hoses between the engine and the stub pipes on the bulkhead, then the heater has not been bypassed.
The feed hose to the heater runs between the back of the cylinder head and the lower stub on the bulkhead. On an M10 it is a straight hose, about 300mm long, with a right angle bend at one end and another right angle bend at the other end, facing the other way.
The hose(s) from the top stub on the bulkhead will eventually connect back to the thermostat housing, but I don't remember exactly how, and I don't have an E30 with a M10 engine any longer to check on, although I do have an M10 which still has the feed hose on it.

Every E30 I've ever worked on, and any BMW generally, has used standard jubilee type stainless steel hose clips for every application, right up to the time they introduced those horrible clip on things.

[damers2000]

when I get the car back I'm going to have to get a better look at it and try and figure out what has been removed, if anything. On some photo's I have seen, and as you also say Brian, down besides the engine there should be a metal pipe which the hose connects to. This is only something I have found out since creating this thread and having lots of helpful feedback so, once I get the car back, I'll have a more thorough look at it. The blowers did turn on when I last had the car running and even at temperature there was no heat blowing out

[Satan]

My advice get a car with a 2.5....... rarrrrrrr ;o))))

[martauto]

My advice get a car with a 2.5....... rarrrrrrr ;o))))

Mart.

[damers2000]

My advice get a car with a 2.5....... rarrrrrrr ;o))))

hahaha

My little old E30 could have no engine and i'd still love the thing, especially after I've been wanting to buy this car since I laid eyes on it way back in 1992

[martauto]

My advice get a car with a 2.5....... rarrrrrrr ;o))))

hahaha

My little old E30 could have no engine and i'd still love the thing, especially after I've been wanting to buy this car since I laid eyes on it way back in 1992

Mart.

[Brianmoooore]

BMW chose the M10 to base their most powerful ever car engine on, (all 1200 bhp of it), not the M20.

[martauto]

BMW chose the M10 to base their most powerful ever car engine on, (all 1200 bhp of it), not the M20.

Mart.

[Satan]

BMW chose the M10 to base their most powerful ever car engine on, (all 1200 bhp of it), not the M20.

It Mart put that in the Baur the acceleration would tear the Targa roof off...........

[martauto]

BMW chose the M10 to base their most powerful ever car engine on, (all 1200 bhp of it), not the M20.

It Mart put that in the Baur the acceleration would tear the Targa roof off...........

M10`s are good but they dont accelerate, they change speed gradually

Mart.

[Satan]

You'd lose your syrup as well......

[damers2000]

If there are connected hoses between the engine and the stub pipes on the bulkhead, then the heater has not been bypassed.
The feed hose to the heater runs between the back of the cylinder head and the lower stub on the bulkhead. On an M10 it is a straight hose, about 300mm long, with a right angle bend at one end and another right angle bend at the other end, facing the other way.
The hose(s) from the top stub on the bulkhead will eventually connect back to the thermostat housing, but I don't remember exactly how, and I don't have an E30 with a M10 engine any longer to check on, although I do have an M10 which still has the feed hose on it.

Every E30 I've ever worked on, and any BMW generally, has used standard jubilee type stainless steel hose clips for every application, right up to the time they introduced those horrible clip on things.

After doing a bit more digging around, removing the air box etc so I could take closer look, I think you have hit the nail on the head with your diagnostic!

The connector to the rear of the cylinder head appears to of been blocked off with some type of silicone, although it does also appear to be damaged.

The bottom hose from the bulkhead, which is the bypass, just connects straight into the system at the front of the car behind the radiator. So, that would explain why my car has no heating, the flow from the engine is no longer there, so water would possibly just get luke warm only.

So, as far as I can see, I need two parts to correct the bypass. One of which is a connector and the other a hose. I don't suppose you would know the part numbers for these items? I think the connector is 11121250746 but can't be sure as I don't have anything to check against. I haven't got a clue what hose I would need.

In addition to the above, I would also need a replacement hose for the one which has been spliced at the front of the car which I think is 11531276541.

I have attached some photo's below but you can see to the rear of the cylinder head, there is northing other than a lump of silicone type material

[minesapint]

This work to bypass the heater has been done for a reason, and that is almost certainly the heater has been leaking.
So in restoring this pipework back to original be prepared to expect a wet interior.
My approach would be to investigate the heater, it’s valve and matrix before filling it with coolant, that way you won’t get a wet back whilst grovelling on the floor of the car!

[damers2000]

This work to bypass the heater has been done for a reason, and that is almost certainly the heater has been leaking.
So in restoring this pipework back to original be prepared to expect a wet interior.
My approach would be to investigate the heater, it’s valve and matrix before filling it with coolant, that way you won’t get a wet back whilst grovelling on the floor of the car!

Thank you for this but both pipes are still present on the heater matrix so I dont think it is leaking

[Brianmoooore]

If the heater isn't leaking, then why would this have been done?
At least, fill with plain water initially, rather than coolant mix.