Fuel pump replaced, Questions answered

[johngreenedc]

Finished replacing my fuel pump today, after getting the correct replacement pump. It appears that the pump originally put in my 525 was the one used for the 540. While it is made by Pierburg it is listed as a Bosch by BMW. Even the brand new 540 repleacement pump assembly (with the housing, screen, etc.) at $300+ is listed as a Bosch part but is actually a Pierburg. this adds a third pump possiblity for replacement.

New pump ($125, 1 year guarentee) fits the old assembly perfectly, including the screen.

Tips:
The write ups on E34BMW.net are very good and valuable bu leave out a few things. The hardest part of the remove and replace was getting the old pump out of the basket and the new one in. There are actually three peices to the basket assembly. The outer piece with the clips that hold the fuel pump in the tank; the middle piece which attaches to the outer via with four rubber arms; and the inner sleeve which holds (contacts) the pump. The Pierburg pump has a ridge about an inch or so from the top edge which fits into an indentation on the inner surface of the sleeve. I removed the old pump with brute force. I wanted to be more careful with the new pump and was able to examine the ineer sleeve better without the pump in place.

It turns out the inner sleeve needs to be removed from the middle piece, just by using mild pressure. There is a gap along the sleeve which compresses to let the sleeve move. Once out the gap expands to allow the pump to be slipped into place. Then the ineer sleeve slids easily into the middle piece.

The bracket in the tank is only slightly offset from the opening and I found it easy to release and reinstall the pump assembly. To avoid the gas on skin problem I bought chemical (gasoline) resistant gloves, cut the fingers off the left glove, put on the right, pulled the sleeve "extender" over that, secured with duct tape and had a glove that covered up to my elbow. Did not have to put up with washing gasoline off my arm.

Overall, the job was very easy, other than the difficulty finding out which is the correct pump. My total cost was 125 (fuel pump) + 20 (filter) +8 (fuel hose [one hosehad a pinhole leak after filter replacemt]) + 20 (fuel pump relay) for a total of $173. Not bad considering the stealer wanted $600 to 650 just to replace the fuel pump, and some independents were upwards of
$450. Best estimate was $350.

thanks to those whe replied to my earlier post with suggestions.

By the way: car started immediately and seems to be running very well.

John

[Dave M]

Thanks for the follow up John. I will be looking for a pump once the 525 is away for the winter.

Hope it works out.

Dave M