1998 V70 Timing belt, cylinder head work 330k miles!

Post by **abscate** » 15 May 2015, 09:53

I was wondering why you were using used valves - I just looked up new ones...80 USD each x10..OUCH!

5rivers · Post by **5rivers** » 16 May 2015, 05:35

Yes, abscate, they are pricey!!
Will immerse them in oil. Thanks for the replies!

5rivers · Post by **5rivers** » 19 May 2015, 07:09

I picked up another cylinder head (from a '98 S70 turbo) from the salvage yard so I could take out the valves and install them in the cylinder head from my '98 V70 (non-turbo). My question is this: does it make sense to use the salvage yard cylinder head on my car (after cleaning up the head and re-lapping the valves) or should I just install the "newer" valves into the head from car? The cylinder heads are the same. I have not checked the bolts for the exhaust manifold yet, but they seem to be interchangeable as far as length and diameter concerned. One more note, on the cylinder head from my car, one of the valve wells has two or three small scratches on it (photo forthcoming). Is this cause for concern?

5rivers · Post by **5rivers** » 19 May 2015, 08:56

The scratches I noticed are in the valve stem area where the spring is located. I don't think this would cause a problem, but wanted to put the question out there just to be sure.

: valve stem area.jpg (36.14 KiB) Viewed 1049 times

This is the valve that came out of the head/valve stem area where the scratches are on the sidewall. I did not notice any unusual dents or imperfections on the valve seat or on the spring (aside from the valve being bent!). I do not know how the scratches could have gotten there. It is possible it is the work of owners/mechanics previous to my ownership of the car.

: bent valve.jpg (29.6 KiB) Viewed 1049 times

Appreciate your thoughts!

5rivers · Post by **5rivers** » 20 May 2015, 09:12

Here are more pics of the bent valves, and the "newer valves" from the S70 Turbo. I hope it is possible to see the special coating on the "newer" intake valve and on the valve seat. My question is does the special coating on the valve seat remain there or is the surface of the valve seat supposed to be cleaner? A similar coating (although whiter) is on the bent intake valve seat.

: Bent valves2.jpg (26.41 KiB) Viewed 1040 times

: Newer valves.jpg (29.89 KiB) Viewed 1040 times

: Seat coating.jpg (117.32 KiB) Viewed 1040 times

It looks like all 10 intake valves have various degrees of bend and 7 of the exhaust valves have a more visible bend; all extracted from my V70. This should provide evidence of appreciating the installation of a new timing belt and water pump as a preventative measure. In my case the water pump starting making noticeable noise the day before the belt shredded apart due to water pump failure.

One more question: how does one inspect the integrity of the valve guides? Do the valve guides come out and if so, what is the extraction process?

Appreciate any/all replies to my questions on the "newer" valve seat and valve guides! Thanks!

Post by **abscate** » 20 May 2015, 11:01

On the valve guides - I think you just look at the wobble in the valve to gauge the wear. If you went to the trouble of extracting them, you would put new ones in.

Ill let the Vexperts chime in on the valve and coating issue

Post by **precopster** » 20 May 2015, 12:12

The head needs to be heated in order to extract and replace the guides.......best left to an expert. Yes and excessive side to side "wobble" is pretty much the measure of a worn guide. If it feels like the wobble is smaller than a bee's genitals you should be fine

Those S70 turbo valves look like aftermarket standard non-sodium filled valves. Not really a problem as the Volvo part number for valves is now shared with non-turbos so I doubt you're getting the same valves from the dealer as originally fitted.

Won't hurt to lap the used valves in to the old head. When you visit your machinist he will do a hardness test on the head. This highly technical test consists of a long plastic pill bottle without ends with a small ball bearing inside. You drop the ball bearing onto different parts of the head to see how much "bounce" the bearing has. The sides of the pill bottle have marked graduations. Choose the head with the highest "bounce"

I wouldn't sweat on those scratches....not one bit.

5rivers · Post by **5rivers** » 20 May 2015, 17:09

Hi Mike,
Thanks for your reply and analogies!! Indeed I thought they were non-sodium filled valves as well. In fact as I was removing the head bolts, some appeared to have much less torque than others. That was great for my deep well sockets, at least I had a feeling they were not going to crack!

Any thoughts on the black material on the valve seat (see photo above)?

Cheers...

Post by **precopster** » 22 May 2015, 14:51

The bottom of the valve face is not the valve seat. The valve seat is the area of contact between valve and head which is typically about 3mm wide.

The bottom of the valve with the textured finish is simply coated in carbon. Just clean it off.

clifford06 · Post by **clifford06** » 22 May 2015, 19:44

Greetings. These valve pics are probably what I going to find this weekend when I pull my head. If so, a engine swap maybe coming. 2.3 heads are hard to find, and valves are costly, complete engines are easier to find. Thanks for posting pics.