1989 750iL Highline refurbish and restore rear subframe and everything under

[fritzenos]

Nordic climate is nasty for cars in general, I love seeing pictures from all of you guys who have cars in dry warm climates, your cars look new. I'd like to thank everyone in this E32 forum, with out the forum, I'd not be attempting this job and I'll try to answer if anyone has questions about any jobs I've done. Most of the DIY jobs have been covered already by this forum.

Anyway my Highline, only seats four people, it's got the rear AC unit with a champagne cooler and the original champagne glasses, tables and foot rests, all i great shape. The car has only had four owners, it was sold new to Belgium and imported to Sweden some 10 years later. When I bought the car in 2012 I knew I had to do this job sooner or later, I'll never ever drive this car during winter, but someone had and not in California.... .

The car was originally equipped with LAD + EDC 1, someone deleted LAD and EDC in 2002, replaced with somewhat lower Bilstein 31322226192 Mtech in front, 33522226194 Mtech in the rear. The LAD lines and bombs were still there, just recirculating pentosin back into the engine room. A few years ago, the car peed pentosin all over the garage floor, so I had to make a U-turn on the LAD lines behind the cover in the front left wheel well to stop the old lines from leaking in the rear.

I now have the car up in the air to make life easier to restore everything. I have my own big blasting box on it's way so I can refinish as much parts as possible, change seals, bushings, fuel and break lines, I bought a new tank, the list is long......

I'm trying to attach pictures, as soon as I can figure out why the forum says I exceeded data quota allowed I'll add them.

750iL.JPG750iL2.jpg

[cirrusblau]

Jesus Christ! That's so high up! How did you get it up there?

[fritzenos]

Well you see my blue mobile lift behind the car in the picture, its a scissor lift (German made) and it actually can be moved sidways from between the jack points. So I lifted the car high on the jack points, off loaded the car on the front cross member (two sides) as well as held it up on the rear subframe and diff, lowered the lift and moved it sideways out from under the car. Then I used blocks of wood the build hight, my jack stands are regular size.

[fritzenos]

I don't intend to restore the LAD system so all of that is removed except the dual vane servo pump line that runs from the servo pump - in front of the engine and around to the right and back under the upper oil pan and out to the left side wheel well to the U-turn I made a few years ago and back to the Pentosin Canister. I been reading everything I can find about deleting the LAD portion of the dual vane pump and plugging it but I don't understand why BMW made the line run all the way around the engine, was this to heat or cool the pentosin flowing to the LAD system? Does any one know if I convert the dual vane pump to single vane and plug it, do I also just plug the return on the Pentosin Canister?

[shogun]

I'm trying to attach pictures, as soon as I can figure out why the forum says I exceeded data quota allowed I'll add them.

apparently a forum software problem with pics uploading at the moment, others have the same prob, I already informed the admin to check.

You can delete on the dual pump the function for the LAD, just remove the plug and the piston in the pump and put in a normal bolt. Then the pump does not generate pressure anymore and you can remove all the lines. See my post $81 with pic + below https://www.bimmerforums.com/forum/s...ght=LAD+delete
The connection originally for the LAD line can be plugged with a bolt with thread M12x1,5, picture where the new plug is, the one new, left side next to the drive" >>>>this is only when you want to eliminate all LAD parts starting from the power steering tandem pump and modify the double pump to single pump. So you remove the spring from the one port with + plug and replace it with a simple bolt = tandem pump/LAD pump no longer functioning. Instead of the LAD discharge line from the pump you install a M12x1,5 in the pump , so instead of the LAD line a plug to close the outlet on the pump.
In case you do not eliminate inside the tandem pump the function of the pump for LAD, NEVER close that with a plug, always make a return line, otherwise the pump will be destroyed.

[fritzenos]

But I need to plug the return inlet on the Pentosin reservoir also I presume, to be able the remove LAD return line that goes to it.

[shogun]

Here are more pics in post #17 how he elininated the LAD part of the double pump and then he used a repair seal kit for the pump I sent him.
Translate:
eine andere Möglichkeit um die Niveau abzuklemmen wäre es die Servopumpe etwas umzubauen und abzustopfen. Habe dazu im Forum schon nachgelesen aber leider nur ohne Bilder. Nachdem ich mir vom Erich den Dichtungssatz für die Servopumpe gekauft habe, wollte ich es im Eigenversuch auch wagen und habe ein paar Bilder dazu gemacht. Bin danach auch einige Km. gefahren ohne dass die Pumpe sich verabschiedet hat.
Es bleibt aber trotzdem dabei, bei Arbeiten an diesem System sollten nur "Fachmänner" ans Werk gehen, da es bei fehlerhaften arbeiten an die Sicherheit geht. Deswegen möchte ich auch für evtl. Schäden nicht grade stehen.
Die weiteren Bilder von der Überholung der Pumpe mit Dichtsatz wurden von Erich ja schonmal hochgeladen. Deswegen bezieht sich mein Post rein auf die Niveau. Meine Bilder kann ich aber gerne auf Anfrage weiter senden.
Nun zu den Bildern: An der Pumpe müssen die beiden Schrauben mit dem + aufgemacht werden, habe mir dazu anfangs eine Schraube in mühevoller Arbeit angefertigt...aber nach etlichen gescheiterten Versuchen habe ich mir eine Mutter darauf geschweißt. Hinter den Schrauben kommt eine Feder und so ein kleiner Stift mit Löchern hervor. Diese habe ich entfernt. An sich wäre es mit der Niveauarbeit schon gewesen. Aber um die Funktion nachvollziehen zu können, habe ich die Welle mit Hilfe einer Presse ausgebaut ( Im Zuge der Abdichtung wäre dies sowieso von nöten gewesen um den Simmerring zu tauschen). Nachdem bei meinen ,,Plus-Schrauben" zwangsläufig Muttern drauf geschweisst waren, habe ich einfach neue Schrauben besorgt. Gewinde ist M18x1,5. In meinem Fall habe ich einen Lamdasondenstopfen besorgt. Zum abdichten eignet sich der O-Ring aus Erich's Dichtungssatz. Den Anschluss für die Niveauleitung habe ich mit einer normalen Schraube M12x1,5 abgestopft
https://www.7-forum.com/forum/showth...pe#post2606743
He did not eliminate the return line, just left it there w/o function, but you could plug the LAD return line I assume. It goes from the regulating valve towards the front left wheel housing and there behind a plastic cover (you have to remove the left front wheel for access) into engine bay left side along with the 2 fuel lines.

[fritzenos]

Thank you! Yes I've read all these before, reading earlier threads, before posting about this. All the LAD lines, fuel lines and brake lines are removed, it's just the one LAD return line from the u-turn in the wheel housing and back to the canister and the output which goes from the pump around the engine which need removing. Getting my hands down under the canister in the engine room to reach the return line is challenging on the V12. The line is in poor shape where it enters the engine room that why I wish to remove it rather that plugging it in the wheel housing. Here is what it looks like now.IMG_1540[1].jpg

[fritzenos]

I remove the function of the LAD portion of the servo pump as described above, will lubrication of the pulley axel still be ok?

[fritzenos]

Just received my new 102L fuel tank! I think I'll give it a few coats och 2-component epoxy primer and a top coat before installation. Going to try to reuse some of the old mounting parts and clean the fuel pumps before installing them.tank.jpg

[fritzenos]

To my surprise yesterday while I was ordering a few parts for the new fuel tank, I found that it doesn't have a drain. My original has a drain and plug, this one does not. I've told BMW about my concern in this matter, I think it's a mistake in the aftermarket manufacturing, the drain plug is clearly a need-to-have and for future repair I'm sure someone will need to drain the tank for security.

Anyway I'd like to ask if anyone on our forum has replaced the 3 rubber differential bushings that sit in the rear subframe? They seem to be more difficult to replace than trailing arm bushings, and Bentley calls for special BMW tools as usual.

[shogun]

Tank: Both possible, last year we disassembled a 11/93 750iL Highline and that tank also did not have a drain, my 11/88 750 has one, apparently at one time during the production they changed to non drain version. From experience I know that the drain does not drain the tank cpl. as the bottom is not straight and has some spaces where still fuel remains, best is to remove the fuel pump and sender and pump it out there, if necessary.

which bushings exactly? item no.? http://bmwfans.info/parts-catalog/E3...wse/rear_axle/
for these bushings we used a HF C-clamp like Erwin shows here, maybe for your purpose also? http://www.bimmerboard.com/forums/posts/507089/

[fritzenos]

[COLOR=rgba(0, 0, 0, 0.87)]33 171 140 308

[/COLOR]
33 17 1 131 903

http://bmwfans.info/parts-catalog/E3...ier/#1140308_4

[fritzenos]

The bushings that the three differential bolts mount through. The outer race is fairly thin and they sit deep into the rear axel carrier. I'm sand blasting my parts and repainting, since I'm replacing all the other bushings, it feels stupid to not change these as well. Thank you for the answers, I've removed my trailing arm bushings with help from other write ups, but these.....I don't know if I should attempt.

[shogun]

Rubber Mountings 33171140308 I never changed so far. No idea how difficult that is.