1966 Volvo 121

[BenHar]

I don't really know what it will prove knocking it into neutral at 70.

If it stalls straight away or only when it comes to a halt it will give some indication of what the problem is.

Ben

[Scruffy Bodger]

How'd a breather cause it?

Depends on the setup if linked at all to a carb? PCV installed on it somewhere that's gummed up like one on an old Pinto?

"Can PCV valve cause stalling?
A faulty PCV valve can cause a number of problems: 1. Rough idle or stalling: If the plunger is stuck open, the PCV valve will allow too much air to enter the engine. This can cause a lean air-fuel mixture, resulting in a rough idle or stalling"

Just chucking it out there as most of the things any of us would try have been tried already.

[Hooli]

Makes sense now ta, I hadn't thought of that.

[Warren t claim]

Makes sense now ta, I hadn't thought of that.

Won't a car that age have a catch can instead?

[Eddie Honda]

Catch can? How posh, I only had oldies with a dump it out to the road pipe!

[quietside]

If you were to knock it into neutral at 70mph would it just die or return to idle as it's rolling?

This is a good question.

What's the answer?

Ben

Sorry, you're right.
Shocking day yesterday. Worth a try.

[quietside]

UPDATE:

Had a mate of a mate come over today because he didn't understand wtf the car was doing and when I took him out in it he was even further baffled.

He reckoned it was down to the mixture setting on the carburettor.

Did the C70/Ben test (not a Bentervention) and knocked it into neutral at 70 and coasted to rest on the hard shoulder.
It stalled around the time it always does going down through the gears (i.e. near stationary) but then easily restarted.

New slave cylinder sorted the psychotic juddering and shaking it developed when I tried (and failed) to take it to Volvo 600.

PS: The breather gauze on the side of the block just vents to atmosphere with a small pipe pointed downwards. No connection to the carburettor on my model but B20s did have such a set up.

[Drum]

Is it when it slows down to a particular road speed or engine speed that it stalls?

[fried onions]

Jon, my twopenn’orth is that you should avoid going down through the gears when slowing down. This is of doubtful value and only wears the gearbox needlessly. This car will stay happily in top gear until about 20 MPH when it can be put into neutral. Brakes are for slowing down, not gears.

[quietside]

That's how I was taught to drive, Josh - and I'm not changing it for the sake of a stupid fault on a car that needs fixing.
Synchromesh exists for a reason.

Some of you seem keen for me to drive around this problem; sorry, but I am not prepared to drive around it.
It didn't do it before and I'm not driving it any distance until this fault is chased out of it.

It wants to stall far less when driven down the gearbox as opposed to being driven to near stationary in top.
It then tries to stall, baulks, but can't quite manage it and stays running.

The only difference between two runs? A quarter of a turn on the idle screw.

If you can infer the fault from that, squire fam, I'm all ears.

I'm off to nick/borrow a known good Zenith 36VN (OEM carb) to see if it is a case of a setting the Weber simply cannot run with.

Is it when it slows down to a particular road speed or engine speed that it stalls?

Road speed, somewhere between 10-20 mph.

No rev counter to gauge engine speed but I could probably get my mate to rig up some kind of nonsense through the bulkhead to connect my multimeter to.