Broke something replacing oil pressure sender unit

[ebmbiker]

Good evening folks,

I've replaced the oil pressure sender unit and now have a major oil leak when the engine is running.

When I was undoing the sender unit the manifold it's fitted to (the square block in the photo) suddenly became loose and easy to rotate. I thought at first the banjo has become loose but that's not it.

I'm guessing the banjo has snapped?? Has this happened to anyone else and how did you fix it? Car is an MY83 SC US import.

Cheers, John

 

 

[Nige]

Is it leaking where the mounting block enters the crankcase? 😲

[ebmbiker]

It’s leaking either side of that block. And because it’s under pressure it’s spewing out. 

[Rustybum]

I replaced my sender recently.

I’d read all the horror stories about the crankcase cracking if you try to undo the sender while it’s still attached to the square block. Loads of advice saying to remove the sender and block in one.

So I bought all the parts listed to re-attach the square block after you remove it. 

So sender, banjo bolt, square block and all the sealing rings. 

The parts are fairly cheap, the square block is the most expensive but I doubt you’ll need a new one. I didn’t but I replaced it as i’d bought a new one anyway.

Fortunately it was a doddle and everything came apart and went back together easily. 

The oil pipe comes off easily, just a little oil dribbles out of it, then the banjo undos from the crankcase, and the whole assembly lifts away.

With a bit of luck you’ll have just unseated a sealing ring so you could just replace them.

Or have you not tightened down the sender fully with a new sealing ring?

A thin spanner is required to get it to tighten down fully.

It’s not leaking from there is it?

Worst case scenario is the crankcase has cracked/broken. 😩

Regards

Russ

[R2D2]

The block does come loose when you are undoing the bolt so no worries there. It look like oil is escaping from between the union block and the case. Did you remember to put a sealing ring between the block and the engine case? I can see one between the oil pipe and the union block but can't see the other side in the photo.

Damage to the crankcase can occur if you try and unscrew the sender from the top of the union block whilst the block etc is still mounted on the engine case. The sender has a habit of seizing to the block and so excessive force trying to remove it can crack the case via the banjo. I doubt you swung off of it like a tarzan and so suspect the issue is simply either banjo isn't quite tight enough or the sealing rings have seated properly. Remember something like 4-5 bar of pressure can be seen at this connection and so oil will escape if isn't appropriately torqued/sealed. Try careful disassembly/ reassembly.

Edited July 26, 2018 by R2D2

[ebmbiker]

Afternoon chaps,

It’s all sorted and no damage done except my pride. Got it to Dave Griffiths Racing, my local indie, and he’s replaced the manifold washers and retightened everything. 

Never again will I wield a spanner without Googleing the procedure first! 

[jevvy]

Excellent news! Dont beat yourself up - no such thing as a mistake, just opportunities to learn something new!

[ebmbiker]

On 7/26/2018 at 3:53 PM, jevvy said:

Excellent news! Dont beat yourself up - no such thing as a mistake, just opportunities to learn something new!

Cheers dude,

I’m my worst critic!

[Phill]

I have just removed my sender as I broke the top of it while removing wiring. It's a very good job this thread was here as a reminder to remove the whole assembly rather than remove the sender in situ. I had to use Normfest Super Crack and heat to shift it, it was that stuck. If I had tried to remove it in situ there would have been crank case damage for sure!!

This is a simple DIY job but could lead to disaster very easily. Perhaps this thread could be pinned as a warning to others? @Von Twinzig

[Von Twinzig]

Duly pinned Phill. 🤙🏻

VT

[Phill]

Thanks buddy