project 1985 BMW E28 520i - Good-byes

[SiC]

More to come later when I write up...

 

[SiC]

My local motor factor got me in a Dizzy cap today. I really didn't want Intermotor but it's all they could get. At 30 quid it was twice the price of the same on eBay, but I dithered too much and didn't get one ordered in time.

Quality unsurprisingly is not a patch on Bosch or Behr.



This post is going to be a bit picture light this time as my phone suffered a oil and water incident on Thursday evening. So it's not working properly which is making it a pain to take photos.

Removed the thermostat. Old was stuck in the housing and took a few taps to loosen.


After cleaning up the surface, I grabbed the thermostat. Not sure why they don't come with one, but I drilled a 2mm hole at the top to assist in bleeding.


Spent a good while flushing fresh water through the system. Currently still full of tap water, so I'll need to remember to drain it out tomorrow and put proper antifreeze in. Weather is supposed to drop to 6c at the lowest tonight, so should be perfectly safe. (Hopefully that's accurate!!)

Replaced the air filter with a clean new one.


Chucked the air filter box back in and strapped it all up.


Then went for a start!

Aww crap.

Slight panic at this point. Nothing I had done should have broken it. But it certainly didn't want to run!

Right so what's wrong? Hmm. Let's just change the dizzy cap and rotor as I have them to hand while the ones in the car are in awful condition.

Also the spark plugs got a soaking when the end of the hose came off during filling the cooling system. So used compressed air to blast that out.

Try again.

Oh indeed.

Right let's engage brain. It's not a misfire as it's running. Just only running on full throttle, but barely and at 2500 rpm. Hmm. That's really sounds like a vacuum leak somewhere. I know the hoses are bad, but none of them looked that bad. But this car is full of vacuum hoses and one could well be holed. Lets have a poke around.


Oh. That will do it. How did that fecker come off.


The taped hose was covering a massive split.


Other hoses are shot too and not grabbing, so found some heater hose to replace what I could. The bottom hose that came off originally goes to some sort of valve that is on the heater circuit. If my memory serves me correct, this opens up when cold to provide the fast idle.


While I was doing this, I replaced the hose that goes to the vacuum advance. I didn't have any the right size, so I nicked some by shortening another elsewhere on the car. It's the red striped hose that is the vacuum hose and it goes to some sort of valve. This goes to the vacuum advance and the blue striped hose is the bit I nicked from elsewhere.


Also decided to replace this very worn brake vacuum hose. If this wasn't already split, it wouldn't be long before it did.


The fuel hose just before the fuel regulator looked like it was cracking too. This is replaced with some genuine Gates Barracuda hose that is fully ethanol compliant. I want to get the rest of the hoses changed out to ethanol grade but I have run out of my personal stash of it. I'll get it done after its got an MOT.


Third time lucky?

It smells pretty rich even when warm to me. I've noticed previously in the MOT history that it's been pretty close to an emission fail. I don't know if that was a cold or warm engine though.

Next thing tomorrow will be to go probing with the multimeter and check the resistance of the thermistors. Either something like that or it just needs a jolly good drive.

I've got new plugs to go in, but the existing ones don't look that bad tbh. Probably could do with a new set of ignition leads but they're pretty pricey. Again something for post MOT.


 

[Bstardchild]

Huge admiration for your electrickery skills - good luck with the MOT

[SiC]

Ordered this for fixing the heater valve issue. It says it's for a E36 but the part number on it says otherwise. I chose this one as it was the cheapest with a decent amount of loom cable on the connector for soldering on to. It does appear the connector is pretty universal on BMWs and MINIs for quite a few years - used extensively as the external temperature sensor connector.


https://www.ebay.co.uk/itm/273983935906

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[SiC]

Drained the coolant to refill with antifreeze and water. Heater valve definitely needs replacing as I think it's creating an airlock back there.

When running up, I did notice that the temperature was getting awfully hot. IR gun on the thermostat housing was reading around 98c at this point. Bleed screw wasn't really releasing any air.



Not sure why it's getting so hot. Possibly an airlock? I did try pretty hard to remove as much air as possible when refilling. I wouldn't think an airlock in the cabin heater matrix should cause this issue.

Maybe the vicious fan isn't very effective anymore? Definitely spins when the engine is running, but I don't think it's getting noticeably quicker when the engine is getting hotter. When I removed it originally, the back did have a distinctive burning smell that you get with old ATF.

While I was there, I dumped the oil and changed it along with the filter. 15w-40 semi-synthetic has gone in.


Then buttoned up the undertray, ready for the car to be dropped down. I don't think there is much else that needs to be done underneath. Fuel filter needs changing but that's at the rear anyway. Tempting to get the garage to do that after an MOT as it'll be a really easy job for them to do.


Finally I had the satisfaction of filling and sticking this on. Also went over the old markings for any future owners.

[Noel Tidybeard]

the gauge isn't "pretty hot" this is an old car where HOT is the red bit and anything between blue & red is "normal"

[SiC]

Nah this isn't a Vauxhall.

Of course it will wiggle around unlike damped gauges but it shouldn't be this high. It's too hot for running at idle in 6c weather. Pretty sure there is an airlock in the heater core due to the valve being busted and blocking the flow. 

[Noel Tidybeard]

viscous fans are the work of the devil as well!

[RayMK]

My E28 520i only began to run hot after towing the caravan, and then only when the viscous fan had begun to degrade.  I did something to mechanically lock the viscous bit so that the fan always turned at pulley speed. I hardly noticed any difference in mpg and there was no increase in noise, but it solved the problem.  

Nice, comfortable, refined, very well designed and constructed cars, although the outer double ball joint per side on the lower front arms became a pain at MOT time when the mileage was around 100K unless expensive BMW parts were used.  Poor quality joints did not last long.

[SiC]

Left the Ozone generator in for a good 100 minutes. Seems to have killed most of the fusty smoke smell. Probably some will like that smell but to me it makes me feel a bit sick. If that does it to me, then Mrs SiC will definitely hate it. Plan is also to run the steam cleaner on the headlining to try removing the yellow tar/nicotine crap stuck in there. Otherwise in a hot summers day, the smell will come back with a vengeance.


Dropped the car down back onto four wheels on the ground.



Fuel warning light has gone out but the fuel gauge isn't registering still. Actually I think it's registering lower than when the light was on.


I went to take a look at the heater valve, but before I did that I found another vacuum hose. I can't see or even feel where this goes but it disappears around the distributor area, so presumably this is the second vacuum line for it.


Completely split at the manifold end. Chopped this end bit off to good part of the hose. This car is so full of vacuum hoses - I think more than any car I've owned or worked on before and I have owned a lot of modern cars.


The heater valve is at the back of the bulkhead and bit of a bugger to get to.


After trying removing the screws and finding the hoses not long enough, I decided to try just taking the top solenoid section off.


I was expecting coolant to be either in here or even trying to escape. Definitely this valve isn't letting coolant through. Undoing the coolant reservoir cap got it flowing up out.


The business end of the valve is pretty messy. Some point in its history the coolant system has been neglected on this car. Iirc it was laid up for a number of years when the first owner died and eventually his son pressed it back into action. No doubt that sitting and then using probably did no favours to the cooling system.


Trying the solenoid on the bench showed it consumed a decent amount of power but didn't do the much in the way of movement.



Stripping it down found it was in a pretty corroded state.




After freeing up the parts with GT85, the solenoid started moving again.


To me that shaft looks like it's missing a c-clip. Perhaps rusted off from the coolant going off?

Playing around with it, it looks like there is a rubber stopper that pushes out the rubber diaphragm to cut the water flow. When not actuated, a spring pulls the shaft back in. With out the c-clip there isn't anything to pull back the diaphragm. Not least there would be back pressure on the valve holding it shut.

The Revs picture of the service diagrams helps visualise how it's supposed to work. On these, it looks like there should be a clip at the bottom.


I should have a box of c-clips around but I'm blowed if I can find them. Mrs SiC will point out to me that if my garage wasn't such a messy state, it would be a lot easier to find things...

Putting the solenoid back into the car and turning the heating control gives a good solid thunk now. However without a c-clip I suspect that forward water flow will simply force the valve shut. Hence giving me the air lock.

Finally there has been an anonymous looking button/switch by the steering wheel that I couldn't decide what it did or even if it was a button. Fiddling with it some more got it to pop out.



It appears to be an electric window disable button. A very weird position for it and even more unusual to not put any insignia on it, to make it clear what it actually does.

In other news, once this heater valve issue is sorted and I check the car isn't going to overheat, I'll get an MOT booked up. Biggest thing that's stopping me right now is actually the ruddy great big skip next to it blocking the car in. That should hopefully be gone next week once our new kitchen is finished.

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[spartacus]

That's an overload switch, it pops out of the windows get something stuck in them, you can just reset them by pushing it back in.

Check that the viscous fan isn't just 'windmilling', it needs to be drawing plenty of air through the rad. Check the rad isn't partially blocked too, otherwise the viscous fan won't work.

[spartacus]

As you're discovering, all those hoses are critical to correct running. They'll nearly all be split near the ends and any convoluted hoses will be split in the depths, making them tricky to locate, they're a bit of a 'mare, some of them are made a specific shape that's difficult to replicate using standard hose sizes.

 

[SiC]

27 minutes ago, spartacus said:

As you're discovering, all those hoses are critical to correct running. They'll nearly all be split near the ends and any convoluted hoses will be split in the depths, making them tricky to locate, they're a bit of a 'mare, some of them are made a specific shape that's difficult to replicate using standard hose sizes.

 

I'm definitely finding this. I might get an assortment of couplings with different shape bends in. Also make an inventory of pipes and replace the lot. However I think I've got the worst ones sorted now. 

RBJ also suggested to take off the TPS and make sure it's not full of oil. Then check the idle switch is being activated at the correct point. Once all sorted the idle speed will need to be tweaked as it's probably been previously adjusted to get around the leaks. 

[cort16]

If you're finding that much gunk in the cooling system it's quite possible your radiator is plugged up. I had issues with my P6 running hot and I tried everything including taking it out and flushing it but nothing worked until I had it re-cored and the problem went away.

[spartacus]

49 minutes ago, SiC said:

I'm definitely finding this. I might get an assortment of couplings with different shape bends in. Also make an inventory of pipes and replace the lot. However I think I've got the worst ones sorted now. 

RBJ also suggested to take off the TPS and make sure it's not full of oil. Then check the idle switch is being activated at the correct point. Once all sorted the idle speed will need to be tweaked as it's probably been previously adjusted to get around the leaks. 

Good call on both of those. There's also a manually adjustable IACV underneath the manifold, from memory, they often get adjusted to 'fix' idling issues caused by split hoses, then forgotten about.

[Bren]

Curing one problem leads you to others.

I am having the same with my SD1. I decided to replace the fuel hoses - it would be wise to service the injectors while they are out. I have refitted the throttle potentiometer only to confirm it is worn out. No longer available, I will see if I can bodge what I have.

[SiC]

Last week I discovered the radiator leaking.



Nothing has been done since apart from being order the second hand one - thanks RBJ for sourcing it. It should be arriving tomorrow.

In other news, it appears I bought just at the right time according to Mr Bell:
https://www.classiccarsmagazine.co.uk/blog/market-insights/market-watch-bmw-5-series-surge/

Which explains why stuff like radiators are NLA for the porridge models like this 520i. Surges only happen when the demand is there still and numbers have heavily dwindled. Hence the parts situation on E28 only specifics.

Will be glad to start to drive this. Can't book an MOT still though as it is still hemmed in by the skip.

Especially as my eye is already wandering and that will only be kept in check by driving it!

[cort16]

I'm guessing you could have had it re-cored if the tanks are okay and you couldn't find a second hand one? With my P6 I had it re-cored for 100 something quid by a company in an industrial estate in Glasgow.

[SiC]

1 minute ago, cort16 said:

I'm guessing you could have had it re-cored if the tanks are okay and you couldn't find a second hand one? With my P6 I had it re-cored for 100 something quid by a company in an industrial estate in Glasgow.

That would have been the only choice if I didn't have this second hand unit coming. Many places don't like re-coring with plastic tanks though. @panhard65 had already contacted the local radiator repair company to me for another job and they said they're very busy. The one that RBJ sourced is only 70quid and looks in decent condition. So hopefully quicker and cheaper than a re-core.

Hoping that the UPS driver doesn't damage it either.

[cort16]

The p6 had metal tanks on it right enough. I see it's got auto written on it do you need to plug any extra holes it has for the gearbox cooler?

[SiC]

Apparently drops right in and you can leave those holes open without a problem. I might plug them up with something though if I can find something suitable.

[billy_bunter]

Enjoying the read. Always wanted the 525e but prices are now out of my range

I managed to get my old Audi rad re-cored by this bloke in Avonmouth.  Arrow Radiators. Was not especially cheap (120ish compared to 80 to 90 plus postage from Germany) but it was a good job and I had it within a week. He actually used brand new plastic tanks that fitted the pattern I had.  IIRC he said he was doing quite a few early golf rads like this. Worth a ring if you get stuck!

For pipes I have used Pirtec.  They sell latest ethanol resistant etc. You might get some rubber pipe for the vacuum hose there.

HTH

[Tadhg Tiogar]

2 hours ago, SiC said:

.... stuff like radiators are NLA for the porridge models like this 520i. Surges only happen when the demand is there still and numbers have heavily dwindled. Hence the parts situation on E28 only specifics....

I had a look at what Walloth & Nesch (usually good for old BMW parts) had to offer in radiators, and even they don't currently have one. They have them brand-new for 518s, 525s, 528s and the M535i, but not the 520i...

Prices are a bit stiff, though. 400 Euros-plus....!

Also the SI board is still available

[SiC]

The lack of spare parts is definitely off putting on the ownership experience. I'm hoping that once this is replaced, it should be ready for an MOT after fixing the heater valve + bleeding. 

I hate the thought of having to go through this pain of trying to source bits anytime something breaks. Really didn't expect this on a German car by a manufacturer still in business. 

[Steviemillar]

15 minutes ago, SiC said:

The lack of spare parts is definitely off putting on the ownership experience. I'm hoping that once this is replaced, it should be ready for an MOT after fixing the heater valve + bleeding. 

I hate the thought of having to go through this pain of trying to source bits anytime something breaks. Really didn't expect this on a German car by a manufacturer still in business. 

I am very very surprised to hear you can’t locate parts for your E28. As mentioned above, Walloth & Nesch carry a large and varied  product line for all older BMWs and have also remanufactured many parts that are available off the shelf too, BMW themselves still stock a vast variety of parts for all models, interior trim is hard to come by but mechanical, running gear and body panels in particular are all mostly still available direct. I never failed to locate new panels and mechanical parts for my E3s, E9s, E28 and the E32 735i that I ran as a daily up until quite recently, I can even still get every body panel for my Z1 if required directly from BMW.. I will agree that some parts can be expensive however they are mostly all still readily available as I’ve found in the 25 years I’ve owned older Beemers.. 

EDIT - Ivo at e28.nl is also a very good source of parts for older BMWs, the E28 is his speciality though, top bloke too.

[Tadhg Tiogar]

5 minutes ago, SiC said:

The lack of spare parts is definitely off putting on the ownership experience. I'm hoping that once this is replaced, it should be ready for an MOT after fixing the heater valve + bleeding. 

I hate the thought of having to go through this pain of trying to source bits anytime something breaks. Really didn't expect this on a German car by a manufacturer still in business. 

These cars are all over 30 years old now. Plastics go brittle and crack, things get dislodged. Nothing lasts forever, even if it was well-built originally.

BMW are better than most for old parts supply (you can still order bits for O2s and E3/E9/E12), but they do work on a batch basis. I had a taste of this during my E24 years, having to wait for bits of trim. I still can't believe I paid £400+VAT for each front wing panel back then....

[SiC]

I am very very surprised to hear you can’t locate parts for your E28. As mentioned above, Walloth & Nesch carry a large and varied  product line for all older BMWs and have also remanufactured many parts that are available off the shelf too, BMW themselves still stock a vast variety of parts for all models, interior trim is hard to come by but mechanical, running gear and body panels in particular are all mostly still available direct. I never failed to locate new panels and mechanical parts for my E3s, E9s, E28 and the E32 735i that I ran as a daily up until quite recently, I can even still get every body panel for my Z1 if required directly from BMW.. I will agree that some parts can be expensive however they are mostly all still readily available as I’ve found in the 25 years I’ve owned older Beemers.. 
 

A lot of parts are available for the bigger and more exotic stuff like the M5/M535i/etc. They're the ones of course that people preserve. Middle porridge stuff like a 520i are harder though. Possibly because many were binned and so not many left. Interestingly the 518i still has a fairly good supply - I guess because, like a lot of cars, the low spec ones are popular with older people who keep their cars longer.

BMW OEM do have quite a few parts available. However they not only seem to be suffering the same problem as other classic car parts being poor quality repro. e.g. the OEM BMW heater valve is no longer Bosch and of poor quality. Then those official parts seem to require you to sell a kidney every time you need something. At least that's what I've found when I've enquired for bits on this. However a lot is surprisingly NLA.

Thankfully a lot of the core engine bits have been used on enough other models that they are readily available. Also the E30 still seems to have a ready supply of parts too and those that are shared, are affordable and obtainable. I guess because there are so many more E30 left around and so a ready market for parts still to be made.

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[SiC]

2 hours ago, billy_bunter said:

I managed to get my old Audi rad re-cored by this bloke in Avonmouth.  Arrow Radiators. Was not especially cheap (120ish compared to 80 to 90 plus postage from Germany) but it was a good job and I had it within a week. He actually used brand new plastic tanks that fitted the pattern I had.  IIRC he said he was doing quite a few early golf rads like this. Worth a ring if you get stuck!

They were the guys I was talking about that Panhard65 had spoken to. Useful to know they did a good job, as I need to find someone for my Dolomite radiator at some point soon. 

[SiC]

Fitted new, second hand radiator today.


Nothing really to say. Single bolt at the top and three hoses to unclamp then remove.


Old radiator is date coded 1998, so not that old.


The leak appears to be because the core is coming away from the tank. Bit of a weird fault and not what I expected, as no obvious reason why it should have done that. Probably repairable?


New radiator is date coded 2009, so a decade newer.


Also put a circlip and washer on the end of the heater valve pintle. Hopefully this will fix it. If the valve still plays up, I'll put the E46 one in instead. The circlip was a bit too big and loose, so I squished it with a pair of vice grips.


Filled the system up the best I could and unbolted + held the tank high to try bleeding the best I could. Couldn't see any leaks thankfully. I'll run it up tomorrow and try getting it up to temperature. Hopefully it will be possible to bleed through and not cause it to start roasting itself again.

[Steviemillar]

Bleeding coolant systems on these older M20B20 (and M30B35) engines can be a challenge. I have used this guide before with success on both my 735i (M30) and also “tailored” the same procedure to my Z1 (M20B25)  when I changed the timing belt and water pump last year, it does work and saves a load of faffing.

https://www.mye28.com/viewtopic.php?f=9&t=58368