Oil Flush Products

becdavies · Post by **becdavies** » 27 Apr 2021, 04:29

I’ve wanted to check here as I’ve been told something by another Volvo owner in my area. I was telling him about the car I have and history - given very little known history and very few km driven (less than 1000 a year the last few years) he said it may be worthwhile putting an engine oil flush through it before an oil change. I was a little surprised as I’ve always thought it was snake oil / marketing but I’ve also heard it can be damaging to older engines as it’s sludge holding it together (it’s a 2001 Volvo). I have a slight cam leak and possible other leaks so obviously engine oil flush can cause more leaks?

Post by **DonnVa** » 27 Apr 2021, 05:42

If you have leaks, you’ll need to address that. PCV and seal age/wear most likely culprits. Mine was a completely clogged PCV, once corrected I replaced the cam and crank seals and I’ve done 5 oil changes since last July. I use a few ounces of Sea Foam before I changed the oil. One time I used Liqui Moly Engine Flush. I’m not sure if the added expense made a difference in cleaning. Based on my experience, I’m sticking with Sea Foam.

becdavies · Post by **becdavies** » 27 Apr 2021, 06:17

The leaks will be fixed soon. PCV is ok according to the tests - glove test gives good suction(no inflating). No smoke from dipstick.

darylrobert · Post by **darylrobert** » 27 Apr 2021, 06:20

Volvo state in the handbook not to add any additives to the oil, i also think these additives are snake oils. I recently changed the oil pan in my 2001 xc70 and was suprised to see no sludge or build up in the pan, i also bought the car with zero mechanical history. use quality oil (synthetic) and drain it when hot.

Post by **kcodyjr** » 27 Apr 2021, 06:48

If you've got weak seals already, a flush is likely to put a marginal rear main seal past the margin.

Installing that $30 seal is either very expensive or very laborious. I wouldn't do it unless you're expecting to pull the engine anyway.

Post by **oragex** » 27 Apr 2021, 07:05

When you change the oil next time, insert through the drain hole a long stick and see if it comes out with sludge. Also pass a small magnet on a wire inside the drained oil to fish for metal particles. Mainly, if the PCV is sucking in properly (see youtube) you should be fine. I did SeaFoam on mine but I was doing it differently. I don't think it would help unclog a PCV oil drain passage or free a blocked oil pick up mesh. What it did however is my oil stays still like dark honey clean after 6000 miles. Not that this means anything because the oil still needs replaced, regardless of how clean it looks on the dipstick, wear is not measured on color.