95 850 turbo bad head gasket , sons 1st car, dad co-mechanic

740GREYGHOST · Post by **740GREYGHOST** » 26 Oct 2014, 09:48

Hey there, my som and I who just turned 16 have purchased a 95 850 turbo, with a majorly overheated engine. The spark plug wire boots were so crispy that we had to "crunch em off" with pliers. So far it's been a good experience. We are limited as far as working space and doing all the work on the driveway. I've gotten the head milled flat and told the shop to only do the valves if it needed it, ( "yeah those valves DEFINETELY needed to be done" he said with a furrowed brow. ) any way the kid bought the victor reinz kit, so far so good. We've got the head back on, new head bolts, torqued per Volvo specs. Exhaust man. on, camshaft cover on. This is where I think I could use a little advice on the timing of the camshafts. Should I put the cam shafts back exactly as I found/removed them? I very carefully marked them, and lined them up like the Haynes manual said, but isn't that when the crankshaft sprocket is at 0 degrees timing? I guess I have to have faith that when I purchased the vehicle it was timed correctly.yes? Thanks in advance. John and Jonah.

Post by **JimBee** » 26 Oct 2014, 10:22

I can't vouch for any of what's in this thread, but there appear to be some expert knowledge and insights here:
https://www.matthewsvolvosite.com/forums ... =5&t=22124

This doesn't get discussed very often. I suspect that's because of the general belief that you can't change the timing on a Volvo, the computer takes care of it. But ah those slotted sprocket holes tell us differently. Why did they make them that way?

Let us know how it all works out!

Post by **erikv11** » 26 Oct 2014, 11:17

I would ignore the timing that was there before, and start over with it done right.

Put the crank on the mark. The mark is not zero degrees, but it is close. Most importantly, the mark is a safe position where the cams can spin freely without damaging anything.

Then you can put the cams in however you want. As long as the crank is on the mark, it doesn't matter. After you have the cam cover on, line the cams up perfectly using the slots on the back. See Volvo 5-cylinder: How to Replace the Head Gasket for rock solid and well illustrated descriptions.

Post by **tryingbe** » 26 Oct 2014, 14:29

Was the block surface check for straightness?

740GREYGHOST · Post by **740GREYGHOST** » 28 Oct 2014, 23:10

JimBee wrote:I can't vouch for any of what's in this thread, but there appear to be some expert knowledge and insights here:
https://www.matthewsvolvosite.com/forums ... =5&t=22124

This doesn't get discussed very often. I suspect that's because of the general belief that you can't change the timing on a Volvo, the computer takes care of it. But ah those slotted sprocket holes tell us differently. Why did they make them that way?

I recall that IPD sells the blue anodized sprockets, those things look so cool! Those killer sprockets have little timing marks on the adjustable exterior slidey parts. I always thought it was so one could advance the timing when going to a stage three or four performance level. JT

740GREYGHOST · Post by **740GREYGHOST** » 28 Oct 2014, 23:14

tryingbe wrote:Was the block surface check for straightness?

Reply to tryingbe, I did not check the block for straight. I guess I didnt even think about it, and now that i think about the block, and its "aluminumness", its a little scary.

Post by **Ozark Lee** » 28 Oct 2014, 23:20

Changing the cam timing (and the ignition timing since the the ignition timing is set by the camshaft position) is possible even with the stock sprockets but there are trade-offs in terms of top end performance and low end torque. As a part of a tune the programmer might specify an alternate cam timing setting but otherwise there is no magic place that will suddenly add 10 or 20 HP to the engine.

...Lee