General No Power after rebuild

[Raymondo555]

Fiat 500 1.3 Multijet 95 Diesel 2010 reg
My daughter’s car had big issues noisy, lost power you name it, its along story ………
Anyway was told it was oil pump. Timing chain and cover etc., she couldn’t afford garage repairs and as I’m retired and used to ‘Tinker’, bought a Haynes manual and said I’d give it a go …….
I had my suspicions and once sump dropped, Wallach! Bits of smashed up shell bearing and No 4 big end cap rattling away nicely.
Engine out crankshaft in a bad way No 4 con rod and big end cap knocked out.
Sent crankshaft to be re-ground, new oversized shells bearings all round and a replacement con rod.
Rebuilt engine new head gasket etc. Sump bolts to casing needed re-threading, thread coils and new bolts fitted.
On start up once fuel got through she stated and runs lovely.
BUT …. Oil light remains on and “insufficient oil pressure stop and turn off engine” warning, she has no power and will not rev over 3000.
Renewed oil switch in case defective, checked turbo operation all seems fine. Checked and rechecked every conne3ction to everything.
There is a clicking sound when engine revved but goes away when settled down to idle, she will start immediately the key is turned and will idle smoothly.
The Oil light remaining on and “insufficient oil pressure stop and turn off engine” warning is exactly the same as before I started .......

All suggestions gratefully received ...... thank you.

 

[portland_bill]

Firstly, I think you may have posted in the wrong section. If it is a 500, it needs reposting in the 500 section. This is 500L, which is the enormous fat MPV thing, so may not get the audience you need for the right help.

If I'm reading this correctly, the original problem also showed the low oil pressure message. But your repair description does not mention a cause or repair for this fault.

The damage to the crank and conrod are likely to be related to a lack of oil. The effect is easily seen, the cause may be more difficult. Have you replaced the oil pump? I understand it is part of the front cover, so quite expensive.

Even oil pumps that are badly worn tend to still give sufficient oil supply, as they usually have an excess of capacity over requirement. So hopefully not necessary to replace it.
Somewhere, either in the pump housing, or very nearby will be the pressure relief valve. This needs careful checking, to be clean and a good fit, and the spring not broken. Sometimes dirt can cause it to stick, causing low pressure, or occasionally excess pressure.
Also, the pickup pipe seal needs to be good, hopefully you renewed it as Haynes suggests, but it needs to be checked that it seals properly, with no air leak. I my Haynes the oil pickup pipe appears to be plastic, so as well as ensuring it is not blocked, check very carefully for any cracks above the oil level, that would allow air in.

With the crank professionally reground, I'd expect the oil drillings to be clean. However, the drillings in the block need to be checked to ensure they are clear.

Logically, there are three options.
1. Air is getting in before the pump, reducing its ability to create pressure.
2. No pressure is being created, due to pump wear or other similar problem. I guess there is some, or it would have seized during your testing.
2. The pressure is being lost, open relief valve, or excess clearances somewhere.

Good luck.

 

[Raymondo555]

portland_bill

Thank you for you answers and sugestions .......

I renewed the Timing cover casing with oil pump and pickup. also the oil drillings were checked and clear.

The original problem we were told was the oil pump.

...... and I will try and repost in the proper place, so many thanks for that too