Inspect exhaust heat shield on the header pipe and further rearwards.

We do not know the condition of the turbo and exhaust securing hardware, yet occasionally the hardware that secures the header pipe to the exhaust manifold can loosen. Though that sound may be a scrape and if looser may be a slight clang.

You can use a spray bottle with a stream or atomized spray and wet exhaust unions with a mix of dish detergent (don't use Dawn, use lemon Ajax or Joy of cheapo) on cold exhaust and spray before and as someone else starts the engine and let idle. Bubbles suggest exhaust leak.

There is a bracket assembly. The top half of the assembly secures to the car right side passenger bell housing bolts. Between that bracket and a securing point on the header pipe is an L-shaped bracket or maybe a flex union to join the two to support the header pipe.

This single union is well neglected by RWD Volvo owners in the overhead cam redblock engine in RWD era from 240 onward. Neglecting this union can cause exhaust union and gasket failure high up including the exhaust manifold to cylinder head gaskets. You replace the studs using Volvo hardware and gaskets. Volvo issued a technical service bulletin on the exhaust studs for all four cylinder overhead redblock.

You will also want to inspect all exhaust support to verify the exhaust is secured and supported properly.

While under there, inspect the drive shaft center support bracket, bushing, and such.

+++++1 on the motor mounts (get OEM or performance like Kaplhenke and Yoshifab) and transmission mount.

The engine, as you accelerate, rotates. The engine pulls up on the smaller mount on the intake manifold side while pushing down on the exhaust side.

At 211k miles, your 1990 Volvo 740 Turbo will require a through inspection and wear item replacement. Suspension bushings, and such. What color is the brake fluid? Black? Flush the brake fluid using a Motive or like power pressure bleeder. Black brake fluid always leads to seized brake calipers and other brake system internal parts failure and corrosion that contact old brake fluid. Use DOT 4 and flush around every two years or so.

Your best resource for Volvo 700-900 series information is in the FAQ link here:

https://www.brickboard.com/FAQ/700-900/


Questions?

Hope that helps.

Unemployed Technical Writer at his Bottom Dollar.
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With the noisy gear engagement, I too was thinking synchros if it was a manual. Don’t think automatics have synchros though. If they do, they probably go by another name.

I like the mounts suggestion and also the idea of driving it under different loads. When doing that try to pinpoint the exact location of the noise. Perhaps it isn’t the tranny at all?

A really bad clutch plate will smell and eventually prevent engagement. Bad bearings will make noise all the time.
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Will I buy another Volvo??? We'll see....

swami ji
Very interesting that the sound could be a starved fluid pump inside tranny!
I thought it was more of a grinding moise - like syncros not meshing - but the noise from a starved pump is also possible...At idle the pump would vulnerable to gunk starvation.

Having the car up on lift for tranny service will also give me access to look at engine & tranny mounts...

Thank you again for your kind response.

jimdnc9