Help with 1999 B5254t - cranks but won't start Topic is solved

Post by **pvfjr** » 15 Sep 2016, 22:26

Hello, I've been trying to put a project car back together that I bought. It's a '99 S70, and it was partially torn apart when I bought it 1.5 years ago. I replaced the head gasket and finished putting it back together as best as I could, but it won't start. It has fuel pressure, and spark. I checked compression, and got really low numbers across the board. I also did a leakdown test, which seemed to give decent results. So, if the rings and valves are making a decent seal, but the compression is low, I have a feeling I may have botched the valve timing.

The engine turns freely by hand and doesn't bind, but perhaps my timing is off far enough to only allow for a partial compression stroke? My compression numbers ranged from 60-80 psi.

I've verified all the timing marks, and everything lines up fine. I'm now questioning whether I bolted the exhaust cam pulley back in it's proper position on the cam, however. Is there an index mark on the cam somewhere that would tell me if it was rotated properly? I had the back end of both cams lined up horizontal before I put the exhaust cam pulley back on, which I thought would give me the right orientation. Of course, now the back ends of the cams are all covered up since I reassembled everything.

I've tried searching for pictures, but there seems to be a lot of variation in these years. Most pics I find are showing an engine that slightly different from mine.

Also, should my cam sensor on the back end of the exhaust cam be pointing downward as I have it? It seems like it could bolt on two different ways...

Post by **pvfjr** » 16 Sep 2016, 19:09

So, can anyone at least tell me which way the cam sensor cover should face? Sensor pointing downward?

Post by **Ozark Lee** » 16 Sep 2016, 19:22

If you unbolted the CVVT hub from the exhaust cam then the only way you can get the cam timing correct is to use the cam adjustment tool. While you might be able to line it up with the rear slots running parallel to the head and cam cover seam (which should be done one tooth off on the initial setup) you can't properly torque the hub to the camshaft without the tool.

The procedure for the cam setup is in this document:

99 XC Cam Seal Replacement.pdf: (3.5 MiB) Downloaded 301 times

The price of the tool has come way, way, down so this isn't quite as painful as it used to be.

...Lee

Post by **pvfjr** » 16 Sep 2016, 20:47

Thanks for that, but fortunately, I did not unbolt the hub from the shaft. The pulley was removed from the hub though, and seems like it could be bolted back on in three different orientations.

Post by **Ozark Lee** » 17 Sep 2016, 07:46

Use the slots on the back of the camshaft as the guide. If you got way off and cranked it with the starter there might be trouble but since you have compression that is greater than zero my bet is that you are OK. Pay special attention to the slots being above or below the centerline, it is real important.

Once the rear of the cams are correct then you can check that the sprocket is properly oriented in terms of the timing mark.

...Lee

Post by **erikv11** » 17 Sep 2016, 08:16

Did you try putting one treaspoon of oil into each cylinder?

Post by **pvfjr** » 17 Sep 2016, 12:24

Ozark Lee wrote:Use the slots on the back of the camshaft as the guide. If you got way off and cranked it with the starter there might be trouble but since you have compression that is greater than zero my bet is that you are OK. Pay special attention to the slots being above or below the centerline, it is real important.

Once the rear of the cams are correct then you can check that the sprocket is properly oriented in terms of the timing mark.

...Lee

So I'm pretty sure the intake cam is correct, since I never had the intake pulley off its cam. It seems there's a chance that the exhaust cam was 180 out though, since there are two different ways to have the slots go horizontal. There is a small notch for indexing the cam position sensor piece that bolts to the rear of the cam though. On this year of engine, should that little notch face up or down when the cams are lined up?

Post by **pvfjr** » 17 Sep 2016, 13:24

erikv11 wrote:Did you try putting one treaspoon of oil into each cylinder?

I haven't. The fact that the leakdown test showed better results than the compression test leads me to believe that it may be something other than rings. Also, I don't think bad rings should keep the car from starting. This was supposedly a running and driving car before it blew a head gasket. Even if it had bad compression due to rings, I would think it would at least try to start. It's not even sputtering.

Post by **pvfjr** » 17 Sep 2016, 14:32

It sputtered!

So it turns out, I did something idiotic. The ignition timing was indeed 180 out of time, because I put that cam sensor encoder wheel (or whatever you call it) back on the cam backwards. I got the rounded tab lined up in one of the big slots, but had the beveled rib 180 out and smashed it when I tightened down the bolt. Since the rib was now so misshapen, I had to use the micro die grinder to make sure it was no longer in the way. Now that the wheel is bolted back on correctly, the car actually sputters!

It still won't start, however, but it's trying. I'm not sure if it's just not firing on all five cylinders or what. Maybe I got the coil pack wiring screwed up and have effectively botched the firing order? The harnesses don't seem to be labeled...

Is there a wiring diagram I can use to check the wire colors and verify the firing order?

Post by **Ozark Lee** » 17 Sep 2016, 14:53

There is a wiring diagram but I can't post it without facing the wrath of the Volvo lawyers.

http://www.volvowiringdiagrams.com/

The pagination is all screwed up but the wire colors to the coil packs is there. Use the ME7 diagram, the Denso wire colors are different.

...Lee