I think I just ruined my engine

it's only running at 300bhp!

exactly

Neil, I once reset computer in Vectra using paper clip.
It was in a limp mode and showing all kind of errors (crankshaft sensor, cambelt etc.).

I've been thinking about this, and I'd rather get a code reader and find out what the engine thinks is wrong, then reset it.

Once reset the codes will be cleared, and I'm interested in what the engine thinks is wrong.

Perhaps the engine could join the forum and give its opinion on BLB too.

I'll ask it.

Let it channel throough prancer.

Any idea what tool you need? Can you get a gunson one?

In terms of a code reader?

Just disconnect the battery and go from there. It absolutely won't do any harm, and will save you a lot of time and money.

Chap who looks after the engine has been in touch- he says that from the description of what's happened the belt will have skipped and the inlet valves will be bent.

So if anyone has any NA cams from a 20V 850, preferably a 93-94 model year please let me know as we may as well chuck some more aggressive ones in as the head gets rebuilt again.

Aaah. The classic telephone diagnosis.

If he's right, a re-set will make no difference, positive or negative.

True.

Diagnosis via PM on a Volvo forum:

"FUCK!!! Always when parking in gear on a hill put it in gear so that if the engine turns it turns in the normal direction of rotation, it should not still jump when turned backwards but should not be tried.

The belt will of jumped a 2 or more teeth if it doesn't start, I'm sure then that it will of bent the inlet valves, the exe ones are less likely to hit the pistons. No piston damage should of been caused with just trying to start it.

I can sort it as soon as I get back."

He is currently in the States.

Oh balls.

@DJ - fuck off. Since when have you been the arbiter of what people can or cannot post on this forum?

Oh balls.

That's what I thought.

At least the inlet valves are cheaper than the (sodium filled) exhaust valves.

It's not the best news I've ever had, but no use crying over spilled milk.

Not a nice feeling though man. I know it too well.

I was reading about sodium filled valves the other night and their merits. The article seemed to think they were overkill and questioned whether or not they actually ran cooler.

With a turbocharged engine the EGT's get pretty damn high, a common problem with the turbo 850's is people running standard octane unleaded, which means that the ECU pulls a load of timing to prevent knock, which means that EGT's rise, which burns out the sodium filled valves.

Running high octane means the engine can run a much more aggressive timing curve which in turn reduces EGT's, but if your in boost for extended periods, and/or it's really hot they can go up fast.

I'll take the marginal advantage that the sodium valves give I reckon.

Then bend the fuckers, it would seem.

Yeah, fair enough. I was thinking aloud.

Wait for your man to check it out. I pooed my pants when I popped the head gasket on the B, expecting a new head and everything to go along with it, but I got away with just the gasket.

It's not gonna start with cam belts out, anyway, so it may just be one valve (if any).

What worries me is that it fired for maybe a second, then stopped.

I suspect that havoc was wreaked in that instant.

Hey ho- I might take the opportunity to put bigger valves in.

Oh I didn't read the bit where you said it fired. When I did it the thing just spun on the starter.
Ran perfectly after the mechanic reset it. But it was an Audi not a Volvo!
But really? how can the belt have skipped?

Not really sure, it just seemed to be the only thing left that it could be.

The tensioner is hydraulic, but can apparently be backed off if the engine is reversed.

People have been making (commonly) 350 whp, 400 whp (uncommonly) and 500-700 whp (rarely, and possibly briefly) on the stock belts, with the stock tensioners and they don't skip.

Combination of wrong gear choice by me, a very steep hill and a heavy car.

sad news ;-(
this thread has been like watching inspector morse mixed with a bit of silent witness

Full autopsy results to come later this month, and hopefully news of the rebirth also.

Combination of being a fuckwit by me and being a fuckwit by me.

Don't beat youself up Neil. Coulda happened to anyone.

That's a pretty fair summary.

OHV engine designed in 1947, computer, what computer? FTW!