XSeries-forum

On the 4.6 has anyone heard about a modification on the oil filter housing to prevent all the oil draining back when the car is stood for a while.

It shouldn’t as there is a non return valve at the base of the oil filter housing. Allegedly.

Definitely shouldn’t drain back, when I got mine when I undid the cap to change the filter the oil pissed out of the housing and the second time, before I realised that two of the petals in the cap were missing and not lifting the filter to allow the oil to drain. Messy

I only ask as someone on the 4.6 facebook group has been talking about something they did to the filter housing to stop it draining back if stood for a while and stopping the rattle on initial start up.

I think that’s a pre-oiler mod. A couple of folks on here have done it. Not sure where it fits or what needs modifying. It’s supposed to ensure the timing chain tensioner has enough pressure right from starting the engine without waiting for the pump to pressurise everything. I think Lez did it to his.

No it's not the pre oiler mod, it's all about the filter housing.
If you join the facebook 4.6 group you'll find out

As said it shouldn't drain back.
Does the petrol filter holder have the small 0 ring at the bottom.
Also the pre-oiler system is the only way to have oil pressure the moment the engine turns and that stops the rattle.
Will see if i can find the article on fb.

There is a pressure relief/bypass valve built into the Oil Filter cap and the Oil pressure relief valve is in the oil pump (I believe there was a Dealer bulletin about it)
When my engine was rebuilt and after a ton of research I went the pre-oiler route full oil pressure delivered on start every time.
Having had the opportunity to examine the remains after oil pump failure I decided the culprit was the Chain Tensioner which operates on oil pressure but does not retain oil pressure it relies on spring tension at cold start. After many engine cycles the spring softens allowing slap, the chain guides having hardened in the same hot cycles wear faster and start to break up. Result even on an engine with regular oil changes is expensive.

If I knew how then I'd put a link up from the FB group, but the guy reckons it stopped his start up rattle, just intrigued really as to how this might work.

The pre-oiling system connects at the oil pressure switch on the Oil Filter housing. At least that's where mine is connected.

weirdfish wrote: ↑Sat Oct 03, 2020 4:08 pm I only ask as someone on the 4.6 facebook group has been talking about something they did to the filter housing to stop it draining back if stood for a while and stopping the rattle on initial start up.

I dont know anythign about the mod per sae, but if it is on Facebook then it must be true.

Surely if chain rattles on initial start up the first thing to do is replace the tensioner. This will confirm if that is the problem and whether the spring has shortened over time. If not then there is another underlying problem like guides broken up. One could argue that greydogs system will hide the fact that the guides are broken until it is to late unless regular inspection is done on guides. Not knocking greydogs system as the guides are likely to last far longer because of not slapping. I change the tensioner every 50k, will probably reduce to 30k as I’ve retired and have shorter journeys and far more stop/start.

I use the x5 very very rarely and sometimes get a momentary rattle on start up for a second or 2, it seems to be top end and comes from the left hand side, it almost sounds like a tappet sort of sound but slightly heavier, I've fitted a new tensioner and it's made no difference.
I was planning on getting the valve clearances done just to rule them out but never seem to get around to it.