Just curious, has anyone come across issues with engines from these years with this problem? My last two bricks (and current) are 93 B230s with squirter blocks... I cannot recall the exact years of the ones I drove when I was much younger, but in doing research on an '88 I'm looking to buy, I came across this notice:

"REVISED CONNECTING ROD

Revised Connecting Rods On
1988-89 Volvo 2.3L B230 Engines

AERA members have reported connecting rod failures in 1988-89 Volvo B230 engines. Rod failures include both bending and actual breakage. Because of the frequency of these failures, Volvo has redesigned the connecting rod for additional strength (See illustration). Engines manufactured as of the 1990 model year use the revised connecting rod.

The revised rod features a thicker beam and has increased in weight by 40 grams. The revised rod should only be installed in complete sets of four, Volvo Part #0271451-7 (four matched rods). Substituting a revised rod, Volvo Part #3531260-2, for the former design will cause an out-of-balance condition and possible engine failure."

This was news to me... I've never heard of this issue but it may be just from lack of owning one... I suppose my next question is, does anyone know if there is a signifying stamp or number range that indicates which engines had this issue and when it was resolved?

On that same note, it appears some of the bore numbers changed around this time...

"Cylinder Block & Crankshaft Change On
Volvo 1988 2.3L B230 Engines

Volvo Motors has changed the cylinder block and crankshaft on 1988 and later 2.3L B230 engines. The changes are related to the crankshaft main journal size and thrust location. Volvo also identifies 1988 and newer blocks by stamping K externally on the front timing case.

Crankshaft main journal diameters have increased in diameter to 2.4798-2.4803 (62.987-63.000 mm). The thrust bearing has been relocated to the rear main and uses a flanged type bearing. The thrust length on the crankshaft was also increased to a length of 1.398 (35.5 mm). Connecting rod journals remain unchanged at 1.9285-1.9293 (48.984-49.005 mm) in diameter.

Revising the crankshaft required the block main bearing bores be increased to 2.6378-2.6383 (67.000-67.013 mm) in diameter."


I guess my question is.... should I be careful about 240s from this period? Any signifying characteristics to determine this?

Many thanks in advance....

It's all true, for what it is. The thinner rods were used in ALL B230 and B230 turbo engines up to about 1990 as you see. They are mostly vulnerable in turbo engines with the boost turned up, primarily when detonation/pre-ignition puts heavy stress on the rods.

Not as scary as it sounds unless you push the engine hard (by this forum's standards; turbobricks.com is another story.) My 1986 turbo has over 500,000 kilometers on the original (small rod) bottom end and runs well. I have the boost turned up to 12psi and other moderate performance mods and sometimes drive pretty hard. Good gas and attention to tuning are important.

OTOH, I recently took apart a 1985 B230FT which had excellent compression and leakdown numbers, had been running great, and found two bent rods. Might have gone another decade, or one more hard run.
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67 144, 85 740T, 86 740T, 91 945SE, BMW R69S, R60/2