1998 V70 XC Head gasket replacement

Post by **Ludermilch** » 28 May 2015, 06:30

Today I am tearing into my beloved XC

I have just wrapped up my stage 0+ and have developed a tiny leak from the coolant system into the #2 cylinder. I discovered it after a rough morning start, then looking into the cylinder the next morning when it was cold and seeing a couple of table spoons of coolant. I am slightly disappointed that I have to take all I have done apart to fix something that was supposedly fixed two years ago. Hopefully in a few day it'll be back on the road providing me joy and function. Plus I'm going out west in 12 days (road trip).

I will be having the head machined to true.

I have done a few engine heads before, Any tips would be appreciated.

Sincerely,
Alex

Post by **Ludermilch** » 28 May 2015, 12:51

Just a few hours to take apart, not the head is at the machine shop.

Post by **erikv11** » 28 May 2015, 13:53

That's quick, clean work, good job.

Unfortunately it is not uncommon for a repaired head gasket to leak two years later. They never go back on the way they came from the factory anyway, there is no way around that. But the big issue is most people don't give careful attention to detail. Without preparing the surfaces well, leaks show up relatively soon. I'll do an engine swap over a head swap any time, there is basically nothing to screw up with an engine swap (of course, the donor engine must be good, but that's another story ...).

Some tips/thoughts offhand:
- For me it is Volvo only on the head gasket make.
- Valve stem seals the same, although perhaps they don't need to be done if the head was off recently.
- Be sure to check the block surface, the head gasket job I botched (my first one) was because I made the block uneven, the head was fine.
- I have always re-used the factory head bolts once, and never re-used any aftermarket ones. That tip came from a Volvo tech who installed dozens of heads without ever snapping a head bolt. But the bolts are getting so old, I wouldn't do that any more.

I sent you a PM.

Post by **Ludermilch** » 28 May 2015, 15:01

This is how the last head gasket replacement was prepped.

Post by **Ludermilch** » 29 May 2015, 17:12

Here is the head, checked out as perfectly flat and presure/vacuum tested. Does anyone's experienced eye see any issues with the valves?

Post by **scot850** » 29 May 2015, 23:06

Assuming cylinder #1 is to the left and 5 to the right, the right of cylinder #1 intake valve (intake is the upper ones?), looks a different color to the other 9. Could be caused by anti-freeze.

Was the head checked for valve clearances. Do you need that on your engine as I think the 98 had hydraulic lifters?

Neil.

Post by **Ludermilch** » 30 May 2015, 04:14

It does have hydraulic lifters. I was unaware that I needed to have clearances checked. I did do a compression test before tearing it apart and all the cylinders were between 151 and 153 in compression.
I believe that you are right about the antifreeze, it had a noticeable leak in cylinder 2 between the cylinder walls.