Hello folks. Have an odd question for the late-model B230F crowd today

Car: 1990 740 GL; B230F. Car starts, idles, and runs smooth as glass and strongly throughout the entire powerband and into kick-down; with no smoke, excessive blow-by, or odd running noises. Car has <40K miles (verified). Uneven starter cranking sound...

Not being experienced with the Volvo redblock side, I was baffled as to why an otherwise normal, young engine would produce a cranking sound which is typically indicative of uneven compression with absolutely no other apparent running issues. In every other typical instance which I can recall over the years, uneven compression (particularly in a 4-banger) will rear its ugly head in both cranking and running smoothness/overall power at one point or another.

No compression tester on-hand, but still

Any thoughts?

Thanks again --

 

Greetings! Hmmm could actually be a faulty starter on its way out?? Post a short video, other members could provide more feedback.

Osss

 

if you do end up pulling the starter motor off, turn the crank around 10-15 degrees at a time, and inspect the flywheel teeth all the way around through the starter mounting hole... probably need a small brigth light and an inspection mirror to get a good look, and someone else turning the crank incrementally.

it coudl just be as simple as a loose bolt or two on the starter.

 

First, take a compression test. It's the easiest and cheapest way to start. Starter/flywheel is a good possibility also.

 

Thanks again, folks.

Was wondering about all of this. The compression maladies which are normally implicated seem out; and, yet, we get the "warped record" starter sound during crankup. Was truly taken aback when I first heard it; but the car idles and runs just like one would expect from an engine with less than 40K and immaculate servicing. Headscratcher...

So, looking at the ring gear as a possible culprit, is there an access plate on the lower bell housing which would allow a slow-turn manual inspection?

Starterwise, the motor cheerfully turns quick enough to trigger the injection system and tickover: Is there something about the non-reduction Bosches which causes this type of behavior when it's on the way out?

FWIW, wish I had some way of recording a vid for reference here; but I'm a neanderthal with a "dumb phone" and the car is not readily available right now for the fun

 

Until you take few tests it is hard to determine what your symptoms are. All we can do is suggest areas to look at but until you look at them it's a shot in the dark. If you don't have access to a lift then I would do the compression test. Also check your battery. As to the starter or ring gear that would be an easier noise to diagnose . We have a 89 740 with 375K miles on it and it has it's orig. starter Engine have never been opened up yet and starts and runs good.

 

Yeah, battery too... A weak battery can give that lumpy ticking over also.

 

true re weak battery. the voltage at the battery really shouldn't drop much below 9V when cranking, if it gets down to 7V things start having problems.

 

I really wouldn't worry about it; a Red Block with 40k, if there are no other symptoms, just drive it and don't pay attention to the lumpy starting. These engines do make weird sounds, had one that sounded like a rod knock, turned out it was a fan belt...

 

i gotta say, my 740 and 240 never required more than about 1 second of cranking to start, even when very cold, so I'm not sure *what* the starter sounds like if its run too long.

 

It's rare but your starter could just be loose, which would cause a grinding against the ring gear. Try tightening it and if that doesn't work pull it and check the 2 gears. If the gears are fine than the starter's probably going out. If it was the engine it would do it at all times.