'98 V70 No compression

Faust · Post by **Faust** » 06 Jan 2025, 21:41

I've just been offered a '98 V70 with no compression in one cylinder, and I am crazy enough to be thinking about it. Aside from a hole in the piston, which I assume would be creating compression inside the block, and easily checked. Is there any common valve problem that would create that situation. He has disconnected the fuel injector for that cylinder and is using the car. If it involves removing the head, I'm not too interested.

Post by **abscate** » 07 Jan 2025, 06:10

It is a head removal job. On these cars, 99% of the time its called a 'burned valve' which is an expression for a chunk of valve has gone missing, so no compression in that cylinder. You could borescope the top if a piston easily, a valve is harder but doable.

Post by **scot850** » 07 Jan 2025, 08:37

You can buy a cheap attachment these days for your cell phone. Buy a cable with the side mirror view that allows you to look up to the valves. I agree with Abscate this, or a less likely holed piston is the issue. Only way to be sure is head removal.

Neil.

Post by **erikv11** » 07 Jan 2025, 09:29

99% it's a burnt valve, which to be clear is easier to fix than a bad piston. But still a hassle.

Faust · Post by **Faust** » 07 Jan 2025, 11:13

Thanks you guys. I am familiar with all of the issues you guys mention, but I was hoping perhaps for a valve train issue I was unaware of. Too much money, effort, for a '98.

Post by **erikv11** » 07 Jan 2025, 11:36

Oh and I did have one engine with a zero compression cylinder due to a broken valve spring, in a 98 S70 NA. But that's not very common.

Post by **Krons** » 10 Jan 2025, 04:31

Faust wrote: ↑07 Jan 2025, 11:13 Thanks you guys. I am familiar with all of the issues you guys mention, but I was hoping perhaps for a valve train issue I was unaware of. Too much money, effort, for a '98.

Sometimes free is too much for a car. Seems more common these days than ever.

Post by **abscate** » 12 Jan 2025, 23:17

Krons wrote: ↑10 Jan 2025, 04:31
Faust wrote: ↑07 Jan 2025, 11:13 Thanks you guys. I am familiar with all of the issues you guys mention, but I was hoping perhaps for a valve train issue I was unaware of. Too much money, effort, for a '98.
Sometimes free is too much for a car. Seems more common these days than ever.

A free Volvo can easily need $2500 of stuff to get it road worthy. True of any brand, really. It’s a common fallacy of owner logic to balance repair cost against “ what I paid for the car” or “ what the car is worth”. That’s strictly a flipper mentality.