Technical Oil temperature sender

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Technical Oil temperature sender

CaptainJohn2011

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Hi Guys,

Would appreciate some help here.

The oil temp sender on my Fiat Strada Abarth is broken.

I can find plenty of coolant temperature senders, but no specific oil temperature sender units. According to the manual they are both M16x1.5 units of variable resistors so can I just use a coolant temp sender for the oil gauge or are they different?

Can't make sense of the part numbers unfortunately.

Any help greatly appreciated.

http://www.mister-auto.co.uk/en/coo...-138a-130-tc-abarth-2-0-130ch_v2589_g830.html

Thanks.
 
Hi

The Fiat/Lancia Part Number for the oil temperature sender is 5940619

The water temperature sender P/N: is 4448131

Part (oil) is not available from Fiat but a little Googling should come up with possibilites.

If this all fails then you will have to look at aftermarket Oil Temp solutions.

All this information is available from my website http://www.nick-bailey.co.uk/ritmo_parts_intro.html
 
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Hi Nick,

Thanks a lot for your help.

Yes, I had looked at your site and tried to work it out. Sadly I'm not that familiar with the format and may have got confused. :-(

I was looking here:

i.e 2l version oil sum and crankcase covers.
http://www.nick-bailey.co.uk/Ritmo_Parts_Web/Pages_S1-S49/s13-2.jpg

And assumed it would be the little bolt like device on the left middle 14325011, which seemed to match what I see on the car and the thread size according to the manual i.e. 16x1.5.

I did try the part number above and it seemed to be an oil pressure sender.
 
Yes 5940619 is the low oil pressure switch! Sorry

Look here: "Lubrication"

http://www.nick-bailey.co.uk/Ritmo_Parts_Web/Pages_S1-S49/s49-1.jpg

You are looking for/at the two sensors around the oil filter sandwich plate assembly.

The larger cylindrical sensor on the right is the oil pressure sender unit. The smaller one on the left is the low oil pressure switch.

Now look a bottom/mid rhs of slide and you will see part 4470183. This is the oil temp sender unit.


According to current ePER parts listings:

5971468 - SENDING UNIT
5940619 - SWITCH
4470183 - SENDING UNIT

4470183 is replaced by 7590193 WHICH IS STILL AVAILABLE - Cost around £21.

Sorry I screwed up first time round but at least we got there and lucky for you the part is still available.

I must admit reading old microfiche slides is a bit of an art and as every year goes by I get a little rustier at it. Not enough practice :)
 
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I would also add are you sure it is the sender unit that has failed.

Suggest you check it and the wiring to the dash board.

The send unit is located on the side wall of the sump. Check with a meter it will have a restance of say 1000 ohms. Don't know what the value and range should be but there should be a difference in values between HOT and COLD.

As for wiring then the back of the intrument dash is probably the most likely cause. These are notorious on 80s Fiats for being a problem, especially on low current/signal devices like the speedo, tacho, fuel, temp and pressure guages. The flex circuit contact areas get oxidised over time.

The best thing you can do is to carefully remove all the connectors and take the dash out. Then use a carbon fibre PCB cleaning brush or a very fine emery cloth (1200 - 1500 grade) and gently polish the contact strips.

Then look at each connector and each of the terminal fingers. They should all be square and facing each other with about a 1mm gap between opposing faces. If one has a much larger gap then gently tease the gap down by hooking the appropriate leaf finger pawl and pull the gap down. Usually only one finger is spaced too far away from the other.

Before putting barck together gently spray/lubricate the flex circuit contact strips and connects with Switch Cleaner & Lubricant. (Radios Spares, Maplins sell this and I think Halfords and Screwfix also but you will need to check).

With a bit of luck your sender is ok and it is just a contact issue.
 
Hi Nick,

Really great info thanks. Must be honest I'm used to just walking into the dealer and going "Gimme". It's my first older car so thanks for the help.

I found the sending unit and the wiring to it which luckily is intact. The sending unit has just lost the little metal tab (not sure what it's called) that the sending wire plugs into.

I've tried to solder it back but I can't get the switch unit hot enough to melt the solder and form a good seal. In fairness I only have litle electrical soldering iron for PCBs etc where I usually have the opposite problem!

I could take it out and get someone with a bigger soldering iron to fix it I suppose. It's pretty bashed up/oily and so on so not sure how permanent a joint it would get and wanted to compare the cost with the new part.

I found a few sites in Russia which appeared to stock the items, I would probably have ended up paying import tax on 16x1.5 bolt!

As a test I held the wire in place and got the good lady to check the reading on the dash when the oil was hot. Not too practical for driving along but confirms an apparently easy fix!

Once again thanks Nick! I'll let you know how it goes.
 
Great news.

A small soldering iron is not really going to really get a good job done.

If I were you I would look at removing the sender unit by either jacking the car up heavily on one side or draining the oil from the sump.

Once the sender is removed you can give it a good really good clean. Then you will be able to see how much "meat" contact material is left onto which you can attact a new spade/other terminal.

Soldering may not be the best solution. I'm thinking what is really required is a short very high heat / molten metal method such as arc/mig welding. Basically a very localised melting/vapourisation of metals.

You would ideal need to check metal of the remaining electrode on the sensor but with luck it will be some form of coated steel. If copper then I'm not sure but the process outlined below should work.

1) clean up the remaining electrode/terminal on the sensor
2) make a new connection plate with excess material/second connection tab.
3) drill a hole in the new connection plate so that when overlayed on and in contact with the remaining sensor electrode/terminal BOTH will be accessible at the same time for a mig or arc welder and in contact with each other
4) connect welder earth to excess metal/2nd connection tab and spot weld.

The idea is no different to surface spot welding panels together. i.e. drill a small hole in one panel and weld throught the hole to the panel below.

Any decent engineering/welding company should be able to do this but with a new sensor only costing £21 I would have a go myself with the weld OR a large soldering iron.

Would NOT recommend a small welding torch due to the plastic/composit sensor end housing.
5)
 
Great advice Nick. Whatever I do it will be next oill change. Can happily take my time with an empty sump.

Sadly I am lacking pretty much all metal working tools. The best I can do is a torch I use for domestic plumbing. Far too risky to use it by the car, but may work when the sensor's removed.

What's left on my car is missing all of the plastic assembly and there is almost no metal left I could attach to. I'll see if I can get a photo. This invariably begs the question What on earth happened to it? The sump is otherwise in good condition so who knows?

I must admit I'd spotted the ebay item but was initially doubtful because it looked so unlike what''s left on my car.
 
Bum! Just lost a long-ish post I was writing so I'll try again! (this time a bit more briefly .... sorry)

Sender 7590193 was used on the following cars, so a scrap yard may be of help:

Fiat Uno Diesel R/89 (89-95)
Lancia Y10 R.92 (92-95)
Lancia Y10 FL.89 (88-92)
Lancia Dedra FL.94 T.DS (94-99)
Lancia Dedra Turbo Diesel (89-94)

Before doing any DIY on the sender unit suggest you measure the resistance a room temp (20degC) and in boiling water. With this info you may be able to locate a suitable sender on the Internet that is creaper than the Fiat one.

As for welding you could try your own DIY welding. Old car battery, jump leads and a copper/steel small nail as the welding rod. Remember to use gloves and eye protection please.
 
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