Question about the 'normal sound' of a B230F engine

It should be relatively quiet with a smooth steady idle. There will be a bit of vibration at idle because it is a 4 cylinder. Two of the loudest noises from that engine will be the fan followed by the air intake at any speed above an idle. At idle it should be quiet.

If the engine is otherwise in tune and runing smoothy you may have a leak in the exhaust system. Or, a large leak in the air intake (air filter all but disconnected) can have a howling rumbly sound.

Thanks. I can safely say I don't think it's any of those.

I think in a way, it's sort of like the fuel injector sound - amplified about 5 times.

I still think the diesel sound is most accurate. Like when you're sitting at a stop and a Volkswagon diesel pulls up beside you - you know it's there and you hear the engine.

snipped-for-privacy@cs.com wrote:

I may replace the exhaust manifold gaskets. I checked the bolts and they are in good enough shape to come off easily.

Then I'll check the spark plugs/gaps, as the mechanic replaced them.

Then will come a new valve cover gasket when I check valve clearances.

Pull out the spark plug boots and if you have any black deposit than it is one or more of the exhaust manifold gaskets. If you do not have any black deposit it could still be the manifold gaskets leaking in different direction.

Regards,

Boris Mohar

Got Knock? - see: Viatrack Printed Circuit Designs (among other things)

void _-void-_ in the obvious place

Thanks. I think tonight I am going to "SeaFoam" the engine. I'll post the updates.

Boris Mohar wrote:

Any other Volvo's in your town with B230F engine you could listen to for comparison? Chase one down on the highway and ask them if you can listen under their hood. (Don't try this in LA, might get shot at...*g*)

I thought about that, and yes, there is 1 just like mine in town, and then a 1994. I need to do this.

I think my conclusion is that I will find 1-2 valves out of spec tomorrow when I pull the cover.

Clay wrote:

I find the easiest way to find leaks is wait until the engine is cold, then start it up and feel around the exhaust manifold with your fingers. Be careful as it heats up pretty quickly.

My 1993 940 with the same engine reminds me of an old Mercedes diesel...it's kind of got a rough-ish rumbling sound at low RPMs...it's had that for about the last five years, it seems it developed over time. I'd suppose it's normal, I haven't had any major problems.