PCV Service on 98 v70

mattyice · Post by **mattyice** » 10 Jun 2025, 14:42

Just finished PCV service on my base model v70. Bought it last year and it’s sat for about 9 years before I started driving it. 135k on the odo now. That basically means no matter what it will need PCV done by most people’s standards here it seems.

Used all new Volvo parts for hoses and canister. Pretty easy breezy with all the space in the n/a model too. I do have a cracked lower intake hose now though so I will address that when I can find the part.

Found lots of vacuum leaks including the small line that plugs into the left side of the intake from the lower intake boot. It was practically fully rotten away, didn’t even hold itself together when I pulled the intake out of the car.

All this being said, it feels like a new car. I have so much more throttle response now. Hopefully better fuel mileage too.

All this is to say; do you guys recommend any other service items with doing PCV job? I replaced vacuum tree and all lines I could find. I was thinking of doing an oil change with some seafoam soon to fullly clear out all of the gunk and burned oil everywhere. Thoughts on that?

I’ll be doing timing belt, idlers, accessory belt, and water pump when I have the time soon. Suspension needs help but I am trying to make sure this motor is in shape first. Let me know what you guys think.

Vova585 · Post by **Vova585** » 10 Jun 2025, 15:26

Timing belt and engine mounts would be my vote. While you are at it, replace all cam and crank seals and water pump

mattyice · Post by **mattyice** » 10 Jun 2025, 19:34

Vova585 wrote: ↑10 Jun 2025, 15:26 replace all cam and crank seals

How hard are the seals to do, I dont mind doing it, I have the tools, but if it involves taking the valve cover off I might skip. I don't leak any oil yet and I am gonna choose to be a little bit lazy about this car till theres a problem for a while.

I do have an OEM timing belt, idlers, tensioner and an Aisin water pump. Need to find a good afternoon for it though. I hate working with coolant.

Vova585 · Post by **Vova585** » 10 Jun 2025, 19:48

Plenty of videos on YouTube about how to replace those seals. They are not too terrible to replace. There are special tools to install them to a correct depth, but not totally necessary for a person with more experience. Couple large washers, 2 inch pvc pipe and 2 inch pvc pipe cap can make it way easier. I am not sure if 98 uses the same size seals as newer p2 engines since recently one prominent member shared 3d prints on how to make those seal drivers.

Post by **abscate** » 11 Jun 2025, 02:53

The changes in seals start in 1999 with VVT coming in. 1998 seals are easy to do, especially on a later one with mechanical tensioner

Post by **foggydogg** » 11 Jun 2025, 10:49

mattyice wrote: ↑10 Jun 2025, 19:34
Vova585 wrote: ↑10 Jun 2025, 15:26 replace all cam and crank seals
How hard are the seals to do, I dont mind doing it, I have the tools, but if it involves taking the valve cover off I might skip. I don't leak any oil yet and I am gonna choose to be a little bit lazy about this car till theres a problem for a while.

I do have an OEM timing belt, idlers, tensioner and an Aisin water pump. Need to find a good afternoon for it though. I hate working with coolant.

The timing belt shelf life has expired, do that regardless of miles ( sounds like it's the plan already.)
Search RobertDIY on Y/T , his advice is usually good to follow. One of his 850Rs has over 500k on it.
He doesn't deal with cam seals unless they leak.
The secret ingredient in Seafoam is odorless kerosene. Spend the money on Valvoline Restore and Protect, a couple motor oil gurus have done serious independent testing on it and it works as advertised.
The detergent package in new SP oils is much better than the stuff from ten years ago.

mattyice · Post by **mattyice** » 11 Jun 2025, 22:24

foggydogg wrote: ↑11 Jun 2025, 10:49
mattyice wrote: ↑10 Jun 2025, 19:34
Vova585 wrote: ↑10 Jun 2025, 15:26 replace all cam and crank seals
How hard are the seals to do, I dont mind doing it, I have the tools, but if it involves taking the valve cover off I might skip. I don't leak any oil yet and I am gonna choose to be a little bit lazy about this car till theres a problem for a while.

I do have an OEM timing belt, idlers, tensioner and an Aisin water pump. Need to find a good afternoon for it though. I hate working with coolant.
The timing belt shelf life has expired, do that regardless of miles ( sounds like it's the plan already.)
Search RobertDIY on Y/T , his advice is usually good to follow. One of his 850Rs has over 500k on it.
He doesn't deal with cam seals unless they leak.
The secret ingredient in Seafoam is odorless kerosene. Spend the money on Valvoline Restore and Protect, a couple motor oil gurus have done serious independent testing on it and it works as advertised.
The detergent package in new SP oils is much better than the stuff from ten years ago.

Youre saying the restore and protect has the kerosene or similar components in it already? I typically use VR1 in my euros (aircooled BMW bikes and so far, this Volvo) I swear by the stuff, high zinc content is supposedly known to help out in slowing down the wear people seem to report happening on standard non-synthetic or synthetic oils.

I'm seeing online that it takes 4 oil changes for restore and protect to come into full effect?

I'm not ruling out R&P but the amount of black/dark deposits I saw doing PCV makes me want to give seafoam an honest try. Gameplan for now will be a conservative seafoam treatment in the oil and tank, and change oil to R&P. Got a couple of good road trips coming so Ill put the miles on the first leg of this pretty quickly.

Post by **foggydogg** » 12 Jun 2025, 08:47

No, Valvoline motor oils do not contain kerosene.
Lake Speed Jr. is a petrochemical engineer and developed lubricants for Joe Gibbs Racing, now marketed to the high-performance community as Driven.

He has done a few lab tests covering zinc and other chemicals in modern lubricants.