Thread: RRC 3.5V8 Oil Supply Problem - Help

but I was told that if the pump managed to suck out the oil in the filter, then the problem lies with a blockage elsewhere.

As you say the order is pump -filter.
The filter has a non return valve so not possible for the pump to "suck the filter dry", as the pump does not suck on teh filter it pushes into.
Therefore something is wrong between the pickup and the pump.
My first guess is that the pressure relief valve may be stuck. This is under the big brass nut at the front of the pump. Maybe take out and inspect and give it a polish.
Second guess?- sheared pump drive on the dizzy shaft possibly from wear .
Third?- Filter screen on pickup blocked by crap.
Fourth- main bearing cap has loosened and fallen off , although the filter should be full in that case.
Regards Philip A

I cannot help with your issues but (sorry if telling you to suck eggs) but as you have pulled bits of the oil pump out you will need to prime it before running it as it will often not suck up the oil if it has drained. You will need to pack Vaseline into all the pump gears to prime the pump.

Garry

Micheal, you didn't say whether you had disturbed the pump but if you did then Garrycol x2.

The order is pickup-pump-filter -main galleries-then tappets.

On an engine with 450KK you would have to suspect that a main cap has loosened and the bolts maybe fallen out , as this is a know problem with 3.5s. This would lead to a loss of oil pressure to the rest of the engine.
Or maybe a big end bearing has disintegrated with the same effect. The noise you describe could be a big end.

Does the oil light go out?

If you can get someone to help, pull off the pump end and have someone turn the engine a little. Hold the gears up with you fingers as they may fall out. If they turn it is good. If not the roll pin holding the pump drive has sheared. Of course you would then have to reprime the pump and get a new base gasket , although it would have so much wear anyway that no base gasket might perk it up!

Next cab off the rank is to pull off the sump and have a look and feel of the bearing caps and the oil pickup.

Maybe its something small like the pressure relief valve, but 450KK is a good innings.
Regards Philip A

Thanks guys.

The pressure relief valve is out, and back in. It all looked quite good and not sticking (either burred or gummy).

I'll check the drive as you suggested Phil, otherwise it looks like the sump is coming off.

The oil pressure switch doesn't seem to be working and I can't remember when the last time I saw it at either start up or post service was.

Thanks for the petroleum jelly reminder guys. I had read up on it last night, but I'd rather be told 10 times than not told at all.

I was hoping we could get another 1,000,000km out of car, so we could give D3's a chance to drop in price and become affordable. I may have to start looking at D2s now.

Without further dismantling the best way to test the oil pump is to remove the distributor and make a tool to drive the oil pump with a drill. A good spin up with a biggish drill will soon build up pressure if there's nothing else wrong. As said, check the relief valve first.

Following on it is possible that the pickup is damaged if its gasket to the block has failed but that is far less likely than the relief valve sticking open. Removing the sump to take a look is not hard. On that score I once saw a 3.5 in a 109 stage 3 that had so few oil changes in its life that the pick up sat in a huge lump of gunge in the sump, with only one litre of free oil to work with. The new owner thrashed it and it ran out of oil quite quickly. Needless to say this engine came to me wrecked.

Lastly I have heard a rattle in a plenum where if you put your hand on the plenum top, you could feel it clearly. In that case the intake trumpets were so loose they jumped up and down with the vacuum pulses. Easy fix, just expanded them a little and refitted with some loctite.

PS fix your oil pressure switch ASAP. It is useful.

The sump is off.

It all looks so clean under there. I can see hone marks on the cylinders!!

The big ends all look fine. the was some flat flakey stuff (like hardened sealant) on the bottom of the sump, and a few slithers caught on the pick up mesh, but no sludge and no blockages in the pick up.

I forgot to check the drive on the oil pump. I'll go do that now.

Otherwise, shoud I be using compressed air between the oil pick up and the pump?

The oil pump drive works.

The trumpets all felt secure when I removed the plenum.

I removed both rocker covers and the plenum chamber. Nothing looked broken or bent, and with someone cranking the engine, all the valves went up and down normally. However it was very dry and I didn't see any oil squirting up. I squirted some oil over the rocker assemblies before reassembling.

Oil does not really squirt out from the rocker assemblies. I am always surprised at how dry they seem. So do not think they are not getting oil because of that. I doubt VERY much that you have an oil blockage in a gallery so I wouldn't be blowing air down them as the filter takes out bits down to 20 microns or so which is so small that anything going through would be so tiny it would not block up a gallery.

I still have a problem with the filter being dry. Do you have an aftermarket oil cooler below the filter? as sometimes if the filter non return valve is faulty , the oil can drain into the cooler and oil pump. But in any case the filter will have some oil in it as it sits on an angle.

Was it just after start up that you heard the clattering?

When did you change the oil and filter? If a filter non return valve is faulty it lets the tappets drain back down into the sump.

Get a new oil pressure switch or reconnect the existing one ( as they usually fail ON) and start up and see if the pressure light goes off and how long it takes. Check the bulb by grounding the connector that goes on the switch.
Regards Philip A