Rough idle when hot

[stuart131]

Hello All & Hope youre ok,

Wondered if you have come across this before, 1970 131, single 175 CD2 stromberg. Car starts on the button, runs fine if a bit rattly+ white smoke , however, seems to be mostly on very cold days, when engine hot if you pull up at lights for eg, engine stumbles and if left will conk out. It will always re-start immediately though. I thought it was fuel vaporisation so fitted new fuel pump and routed fuel pipe away from heater hose,rocker cover etc but still happens. Once you give car a couple of revs, the problem clears either completely or for just a while= wierd. Some days doesnt happen at all !.
Whaddya reckon, new carb ? Temperature sensor? can you get rebuild kit for the Stromby?
My Amazon has always flipped the bird to cold weather.....
Any ideas welcome before I shell out £200 on a new carb or even more on counselling.

[Gordon Hunter]

Hi Stuart,

I'm more familliar with the SUs, but did have an early Amazon with a Zenith / Solex downdraught that had similair sounding symptoms. A good strip, check and clean solved the problem (bits of old gasket / crud blocking it up) so, perhaps following the same course of action wouldn't be a bad idea.
If a rebuild kit turns out to be exhorbitant, then I have a couple of spare Strombergs here that you'd be welcome to (one from a running car I broke up)for a nominal donation towards my latest project.

All the best,

Gordon

[stuart131]

Thanks for the reply Gordon, I am extremely grateful to you. Ill give old Simon a buzz tommorow at Brookhouse, see what the damage is and almost certainly be back to you .
Ill strip out the carb tommorow pm and see what gives.
Thanks again , Ill be in touch

very best regards

Stuart

[Martin Burch]

My 140 has a similar carb. It has been rebuilt in the past I think, but started behaving in a similar way a while back. I had a look at the temperature compensator which lives on the side of the carb under a diagonal plastic cover. I gave it a clean and used some carb cleaner spray. It helped a bit.
I am not sure if all strombergs have these devices. Might be worth a try if yours has one.
good luck,
Martin

[amazondean]

The white smoking might only need replacement plugs and points.

My car that I am restoring was white smoking really bad the other week when I struck it up. I replaced the plugs and a new set of points and it cleared it about 90%.

[TomG]

I've been having a similar problem, starts to cough when she get up to temp, and the only thing to solve it is to let her cool down again. Now i've Redexed the whole system, new fuel lines, new fuel pump and checked the heat shield on the carb, new plugs, leads and oil change and new oil filter, no change. So now i've just bought a new carb, (stomberg 175CD), and as soon as i've fitted that, i'll let you know the outcome.

[TomTom]

The only time I've had this was on twin SUs, and they were set much too rich. It got to the point when I was having to stop at traffic lights with the handbrake while revving the accelerator, so the engine didn't die. I had them tuned and balanced and the problem was gone.

Tom

[stuart131]

Just a quick thank you to all who have replied to my query,and Gordon, I have not forgotten your kind offer, just havent had chance to clean existing carb yet.
re the temp sensor at the side, I ve got a reasonable carb from a 140 with this on (the carb is incompatible..long story). Im going to try the sensor from that in the 131 carb. Thinking about it , if its happening only on really cold days then surely this must have some thing to do with it?
Will pop that on tonight and see how it goes tommorow (should be fun in the snow!!!) If no joy then Gordons fund gets a contribution!

PS A chap at work said today, are you driving that thing tommorow in the snow? I replied 1, DONT EVER call my car a thing and 2 yes i bl**dy well am. He expressed concern i may run into something. To which I replied I sincerely hope that if I do its a modern car like yours as I would probably scuff a bumper whilst yours will be in a body shop for a year. Phillistine

thanks again all, similar tales still welcome

all the best

Stuart

[amazon69]

Hi Stewart,
I have the same car/carb etc..definitely worth having a look at the temp
compensator, but also worth not taking it completely apart because the way it works is factory set and an absolute pita to reset. You'll see what I mean when you take it off. A major spraying of cleaner works wonders, but don't lose the rubber sealing washer, or spray it.
The other thing worth checking, as it was a cause of similar symptoms on mine, is a collapsing breather hose when warm. The ones running over the top of the motor can seem fine cold, probably are, but mine squished shut when warm causing wierdness.hth
best,
Dave White

[222s]

Originally Posted by stuart131

A chap at work said today, are you driving that thing tommorow in the snow? I replied 1, DONT EVER call my car a thing and 2 yes i bl**dy well am. He expressed concern i may run into something. To which I replied I sincerely hope that if I do its a modern car like yours as I would probably scuff a bumper whilst yours will be in a body shop for a year. Phillistine

Welcome back

That sounds about right - there's a small crease in my driver's door & the exposed flange on the centre pillar is slightly kinked (no broken paint on either though) and the other car was towed away.....

I haven't driven mine much in the snow (it always melts quickly in London) but when I have, I found that it coped fine. Dad (who had it for 8 years before passing it on to me) has always said that it's great in icy conditions - he reckons that it's something to do with the narrow width but large circumference of the tyres (so longitudinal tyre / road contact area), coupled with plenty of torque so it's happy at low rpm in a high gear.