Timing Belt Job Gone Wrong... '99 S70 T5

Post by **bmdubya1198** » 16 Apr 2016, 16:37

I was replacing the timing belt and components with my cousin and my dad in my cousin's S70 T5 last weekend, and it seems something went wrong. I have a bad feeling that we bent some valves, but I'm hoping for the best.
When we took off the cover, I noticed there were two or three white-out marks on each cam, but they were nowhere near the factory alignment marks. Instead of listening to me, my dad decided to set the cams so that he white-out marks that a PO had put on there were around the top dead center alignment marks on the top t-belt cover. His thoughts were if the cams don't move while we're replacing the belt, we should have no problem. Well, once we were finished, and the crank and cams did not appear to move, we started it up. It ran TERRIBLY. Low RPM, barely ran. The only reason we ran the car for as long as we did (maybe 20 seconds) is because it's been sitting for probably 2 months due to a failed water pump. We had turned it off a couple seconds after starting it, the car did not stall. After that, like idiots, we tried it again. Cranked, but didn't start.
So, today we went back at it. Slipped off the belt, turned the crank and cams to the factory alignment marks, replaced the belt, and tried to start it. Again, it cranks, but it won't start.
The car is a '99 and has VVT on the exhaust cam, and it feels spring loaded when you turn it to advance. When we aligned it today, the exhaust cam was sprung back the the regular position, which is where I believe it's supposed to be.

So, what can be done to get the car running again? Did we bend some valves, and is that why it won't start? I'd rather not see him get rid of this car, I'm afraid a valve job would scare him away.

Post by **polskamafia mjl** » 16 Apr 2016, 18:45

My understand is that with bent valves the engine won't be able to stay running. It sound like the timing is way off though.

Did you turn the engine over by hand first before starting it?

What do you mean by 'failed water pump?' Depending on the failure mode the valve damage could have been done then.

Post by **bmdubya1198** » 16 Apr 2016, 19:01

polskamafia mjl wrote:My understand is that with bent valves the engine won't be able to stay running. It sound like the timing is way off though.

Did you turn the engine over by hand first before starting it?

What do you mean by 'failed water pump?' Depending on the failure mode the valve damage could have been done then.

I don't think we turned it over by hand the first time, although we did today when we aligned the crank and cams.
The water pump was leaking very badly. The car has not been driven at all since the leak was originally noticed.

Post by **kahl** » 16 Apr 2016, 19:19

I would start from scratch using the rear cam locking tool. Going forward setting all marks to factory specs. Hopefully you were only off no more than three tooths on the cam. I believe any more than three you run into metal on metal. Hopefully someone can chime in on exactly how many teeth can be off before metal on metal starts to happen.

Post by **polskamafia mjl** » 16 Apr 2016, 19:28

bmdubya1198 wrote: I don't think we turned it over by hand the first time...

Ouch.

Like Kahl said I would start over with the cams locked in the back.

https://www.matthewsvolvosite.com/forums ... hp?t=54298

Post by **bmdubya1198** » 16 Apr 2016, 20:59

I don't think it was many teeth off. It had only moved slightly. I'll try locking the cams this time! Stupid VVT...

Post by **erikv11** » 16 Apr 2016, 22:15

Once you get the timing all set, and quadruple checked, if it still won't start then I would check the compression. If compression is low think LMS, if compression is zero think bent valves.

Post by **Ozark Lee** » 16 Apr 2016, 23:19

The cam locker is a total waste of time on a CVVT engine.

To do it properly you need to set the engine to the marks and the marks on the camshafts align at high noon to the notch on the cover. Once the belt is on and the tensioner is tight (don't spend a lot of time getting the tension perfect at this point) rotate the engine by hand, clockwise, a full revolution and then continue clockwise an additional 90 degrees past the camshaft marks.

At that point reverse the ratchet and rotate it back to the marks counterclockwise.

You then need to loosen the tensioner and remove the belt from the cams. Thread the belt back on and as you go across the exhaust camshaft sprocket align the outer part of the sprocket to the mark without moving the center part of the hub.

Reset the tensioner and this time get the tensioner indicator to the proper alignment in the window and then rotate the engine a couple of revolutions clockwise and recheck marks and the tensioner. It is common for the tensioner to need to be readjusted.

The point of that whole procedure is to not only set the timing but also to properly set the CVVT preload.

At that point you should be good to go to start the engine - if it will start. If it doesn't start then start checking the compression As erikv11 said, zero compression would indicate bent valves.

...Lee

Post by **abscate** » 17 Apr 2016, 04:10

I'm sending you good karma, BMW ......hope your engine is ok.

Post by **bmdubya1198** » 17 Apr 2016, 06:44

Thank you! I'll go through Lee's procedure today and report back.