Cerbera 4.2 oil pressure

Cerbera 4.2 oil pressure

Author
Discussion

Hobby1964

Original Poster:

6 posts

34 months

Monday 7th June 2021
quotequote all
Hi, I'm looking to fit an oil pressure gauge to check the oil pressure as the dash gauge is reading low. Has anyone else done this? Any suggestions please as to where to take off from?

WIL35

525 posts

210 months

Monday 7th June 2021
quotequote all
Hi, the existing oil pressure gauge picks up from centre of the V, underneath the coils packs.

With a 4.2 it can be accessed without taking the throttle bodies off, but you just need smallish hands and some fairly long pliers (and a device to pick up the washer and bolts that you drop!). I had to get to my sender last week. I just took the dipstick out, disconnected the injector connectors from the back four injectors to make some space. Remove the coil packs, I left the HT leads connected (no chance of mixing them up), disconnected the ecu cables and slid the coil packs back so they rested on the clutch housing. Remove the plate that the coils packs attach to and the oil pressure dash light sender unit is towards the back of the engine and the oil pressure gauge pipe is just in front of it.

How low is your gauge reading? I have a SPA digital gauge and that reads about 30psi at a hot idle (900-950rpm)

Hobby1964

Original Poster:

6 posts

34 months

Monday 7th June 2021
quotequote all
My reading is approximately only 38psi on cold start, which I believe should be about 65psi. Is there a pressure sender unit or is it a switch?

WIL35

525 posts

210 months

Monday 7th June 2021
quotequote all
That IS low! Have you checked the oil pressure relief spring? That would be worth checking first, it could be broken. Accessible though the offside wheel arch or from underneath, behind a large (22 or 24mm?) bolt

Hobby1964

Original Poster:

6 posts

34 months

Monday 7th June 2021
quotequote all
Yes that was the first thing I did and the new one I fitted was exactly the same length as the old one and I pulled the plunger out to check that was moving freely too

TwinKam

2,969 posts

95 months

Monday 7th June 2021
quotequote all
Hobby1964 said:
My reading is approximately only 38psi on cold start, which I believe should be about 65psi. Is there a pressure sender unit or is it a switch?
It's just a switch for the light, the gauge is mechanical and is fed by the flexi line, they are next to each other.

Mr Cerbera

5,031 posts

230 months

Tuesday 8th June 2021
quotequote all
WIL35 said:
Hi, the existing oil pressure gauge picks up from centre of the V, underneath the coils packs.

With a 4.2 it can be accessed without taking the throttle bodies off, but you just need smallish hands and some fairly long pliers (and a device to pick up the washer and bolts that you drop!)......
This was the best tool that I ever bought for working on a Cerb thumbup

WIL35

525 posts

210 months

Tuesday 8th June 2021
quotequote all
Mr Cerbera said:
This was the best tool that I ever bought for working on a Cerb thumbup
biggrin good choice. I went for one of these, useful for those alloy parts:

https://www.eurocarparts.com/p/sealey-ak653-flexib...

ukkid35

6,171 posts

173 months

Tuesday 8th June 2021
quotequote all
First thing to do is change the Oil Pressure Relief Valve Spring

If it is fractured, make absolutely sure you get every part out

It you can't you must remove the small L shaped pipe between sump and pump, and you must find every part of the spring

It won't become loose in the sump because of the pickup filter

If any part of a fractured spring gets in to the pump, the damage that ensues could make your engine uneconomical to repair




ukkid35

6,171 posts

173 months

Tuesday 8th June 2021
quotequote all
Just seen you have already fitted a new spring - so you can ignore my advice

Oh, and it took over a year from when the spring fractured and the piece was accidently left behind, to when it was sucked in to the pump

Edited by ukkid35 on Tuesday 8th June 20:25

sean ie3

1,990 posts

136 months

Tuesday 8th June 2021
quotequote all
I have heard this can require a full engine rebuild as cam bearings and main bearings can wear and give low oil pressure.