Just did a compression test on my '98 S70 T5, and cylinders were all about 1.1 Mpa (expected range: 1.1 - 1.3 Mpa), but compression built up slower than I was hoping. I am considering trying Zmax fuel system and oil additives to get a little improvement. Interested to hear people's thoughts/opinions of Zmax. Does it do anything at all, or is it basically snake oil?

-AJ

'98 Volvo S70 T5 "Vicky"

 

How many miles on your S70? From what I've heard, ZMAX hasn't worked for the two people I've talked to that have used it. I have heard some that swear by Marvels Mystery Oil, and Lucas products. Also a lot of people recommend Royal Purple.

 

145k on the car. I use Mobil 1 synthetic oil and filters. I have read that slow build up of compression is usually due to wearing/worn piston rings, but I don't have the time, expertise, or desire to take the engine apart. I read that a cylinder leakage test is more useful for finding the source of the leak, which leads to another question I have of how do you know when a piston is at top dead center (required for the cylinder being tested)?

Anyway, just looking for an easy way to get a little better compression. I will check out the products you mentioned, and would still be interested to hear others' thoughts on Zmax or other additives that make similar claims.

Thanks,
AJ

'98 Volvo S70 T5 "Vicky"

 

Everyone i have talked to says they say no difference with them, but i have not tried it out.

 

its junk. i know of a lot more Pierre who have had luck with lucas oil treatment.

 

Try Auto-Rx. This product is a blend of natural esters, primarily lanolin. It can improve compression by removing carbon deposits in the ring packs. I've used it in my 2000 V40 and it seems to have improved my overall fuel consumption by more than 1 mpg.

 

How about Xado Atomic Metal Conditioner? It's supposed to recondition the metal surfaces in the engine and fuse ceramic to metal in friction areas. Like most additives, seems to good to be true. Anyone use this and have thoughts.

-AJ

 

How many kilometers on your S70? From what I've observed, ZMAX hasn't proved helpful for the two individuals I've discussed to that have used it. I be familiar with some that believe by Wonders Secret Oil, and Lucas items. Also a lot of individuals suggest Elegant Violet.