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chad_cra
08-03-2005, 12:45 PM
Hello,

Can anyone tell me what model or # compacitor I will need for my fuel gage in an 89 535i, I saw how I just need to make sure what type to use.

Thank you

Interceptor
08-03-2005, 01:21 PM
Hello,

Can anyone tell me what model or # compacitor I will need for my fuel gage in an 89 535i, I saw how I just need to make sure what type to use.

Thank you
I don't know what type, but I'm sure they're called CAPACITORS :)

chad_cra
08-03-2005, 01:26 PM
I don't know what type, but I'm sure they're called CAPACITORS :)

Ah thank you,
I forgot to mention I can't spell very well and did not want to check against spell checker, however I shall not make that mistake again.

Any assistance would be great though. ;)

SRR2
08-03-2005, 01:33 PM
C-a-p-a-c-i-t-o-r Capacitor.

There were a couple of cluster versions in the early E34s. The circuitry was different and the capacitors required were slightly different numbers and values. You won't know for sure until you open it up. Some of the information I found as to capacitor values was incompatible with the cluster in my car, so you shouldn't assume that everything you read is applicable to your car. In my case I had to do a rush order to get a couple of values I didn't know about.

You can search for more information on this (make sure you spell the words correctly or you won't get any meaningful results) to see for yourself the variety of values. You could try the keywords "E34 cluster capacitor BMW"

I don't know quite what you mean by 'fuel gauge'. Are you saying that the fuel gauge is acting up? Because the capacitors that need to be changed aren't necessarily in the fuel gauge. The most problematic ones are in a switching regulator that powers many parts of the cluster. They're the output filters and when they go bad, the power gets 'dirty' and filled with ripple and hash such that the circuitry in the cluster behaves erratically.

Finally, the other problem you're going to find is that the capacitors available these days won't match up very well with those available in 1988. The newer ones are smaller, value for value and voltage for voltage. Plus, the lead spacing is smaller too, so they won't fit perfectly in the board. The caps you need should be of the low-ESR type, preferably with a 105C temperature rating. these are not available at Rat Shack. You'll have to get them from a real distributor like Mouser or DigiKey. Generally you can use higher capacitance and higher voltage ratings and the circuitry will be just as happy with it. Just be careful that whatever you get isn't too high in profile to close up the cluster.

To remove the cluster, you'll need to remove the steering wheel and, if your cluster is as thick as the one in my car, you'll also need to drop the column. There are plenty of resources with instructions on performing these operations. DISCONNECT THE BATTERY!!!!! By the way, on the earliest E34s, there are *three* screws on the lower steering column cover, one of which may require you to remove the bolster under the column to get at it. That cover is an SOB to get off with the bolster in place.

This is all a PITA to do the first time just in figuring out what you have to remove and how to get at it.

chad_cra
08-03-2005, 01:41 PM
C-a-p-a-c-i-t-o-r Capacitor.

There were a couple of cluster versions in the early E34s. The circuitry was different and the capacitors required were slightly different numbers and values. You won't know for sure until you open it up. Some of the information I found as to capacitor values was incompatible with the cluster in my car, so you shouldn't assume that everything you read is applicable to your car. In my case I had to do a rush order to get a couple of values I didn't know about.

You can search for more information on this (make sure you spell the words correctly or you won't get any meaningful results) to see for yourself the variety of values. You could try the keywords "E34 cluster capacitor BMW"

I don't know quite what you mean by 'fuel gauge'. Are you saying that the fuel gauge is acting up? Because the capacitors that need to be changed aren't necessarily in the fuel gauge. The most problematic ones are in a switching regulator that powers many parts of the cluster. They're the output filters and when they go bad, the power gets 'dirty' and filled with ripple and hash such that the circuitry in the cluster behaves erratically.

Finally, the other problem you're going to find is that the capacitors available these days won't match up very well with those available in 1988. The newer ones are smaller, value for value and voltage for voltage. Plus, the lead spacing is smaller too, so they won't fit perfectly in the board. The caps you need should be of the low-ESR type, preferably with a 105C temperature rating. these are not available at Rat Shack. You'll have to get them from a real distiributor like Mouser or DigiKey. Generally you can use higher capacitance and higher voltage ratings and the circuitry will be just as happy with it. Just be careful that whatever you get isn't too high in profile to close up the cluster.

To remove the cluster, you'll need to remove the steering wheel and, if your cluster is as thick as the one in my car, you'll also need to drop the column. There are plenty of resources with instructions on performing these operations. DISCONNECT THE BATTERY!!!!! By the way, on the earliest E34s, there are *three* screws on the lower steering column cover, one of which may require you to remove the bolster under the column to get at it. That cover is an SOB to get off with the bolster in place.

This is all a PITA to do the first time just in figuring out what you have to remove and how to get at it.

Thank you,
To answer your questions about the fuel gage, it does not work in is stuck on 3/4 tank, however when I turn the car off it does go to empty, but it does not tell me how much fuel I have in the tank, I just assumed that this is also in the cluster, thank you for you help.

Chad

SRR2
08-03-2005, 01:53 PM
Well, unless someone has already renovated your cluster, you can expect it to crap out. However, the fuel gauge stuck at a particular point could be the sender too. They've been known to go bad, and there was some bad fuel from ... who the heck was it? Shell? ... that ruined thousands and thousands of fuel senders. You might have gotten lucky and yours is one of those.

Lucky for you the sender and fuel pump is relativelyl easy to access through the panel in the trunk. I suggest you get the Bentley book for the E34 if you don't already have it, for those instructions.

ukm5
08-03-2005, 07:21 PM
I wouldnt assume its the capacitors and in any case if you have to ask what sort to get then in guessing you have no idea about electronic components and will end up with a mess - it could be the actual fuel needle unit which is a seperate unit in the instrument cluster and can be replaced very easily as it just plugs in. There are tests you can do but id suggest u take it to a garage and have them fix it

Or go with previous advise and check the fuel level sender is sending the correct voltage/resistance

shogun
08-03-2005, 08:26 PM
try to clean the fuel sender unit, read this
http://www.8ung.at/behrens_homepage/maxfretter/gauge.htm