Fuel Starvation

[Paul Greenway]

Sorry,

I mean't to add some more photos.

[davidwheeler]

Very pretty much like mine but I do not have a black bonnet.    I would be interested to know what jets you have fitted.    I uprated my slow running jets to 55 a while back and am about to try some 60s.   I was on the motorway yesterday and felt it was lacking a bit at tht top end so am wondering about bigger mains as well = apparently modern petrol is more viscous than 70s fuel and needs bigger jets (and no, it is not fuel starvation, aready fettled that with electric pump and hi flow filter).

[lancialulu]

I now run standard 42 solexs on standard jetting on my 1600 Sport. I had an odd hesitation sensation every time I wanted to accelerate from a cruising rpm of 4000ish. The car would hesitate for less than a second then had good acceleration afterwards. Tried all sorts to cure and resigned to live with it thinking maybe the Holbay tuned head and cams were to blame (timing spot on). Then late last year I splashed out on an Omicron Group 4 exhaust for the HF which freed up an Evolution Group 4 manifold which I retro fitted to the sport as the car had an exotic long header designed one off exhaust system. This had been designed by a previous owner to lift the max torque to motorway overtaking equivalent rpm. the only problem with this exhaust was it had to go under the subframe not through it. At least once a year it took a bash from uneven roads. Anyway the long and short of it is that the hesitation has gone!! Suspect the exhaust is so efficient a scavenging  the when the engine tried to accelerate the mix was momentarily too weak.

BTW I cant see how changing slow running jets can overcome poor performance at beyond slow running conditions.

BTW2 Anyone want a crazy Fulvia ss big bore manifold free to collect?

[Richard Fridd]

Manifold sounds of interest, is it damaged but repairable?

[lancialulu]

Manifold sounds of interest, is it damaged but repairable?

Actually undamaged after the last repair!! (Now with skid plates...)

[davidwheeler]

They are not actually slow running jets but intermediate jets.  Slow running mixture is adjusted by the 4 slow running screws.  The 55s certainly made a difference.  The 60s have just arrived today - watch this space!

[Paul Greenway]

Undertook a 300 mile round trip last weekend through the Lakes and back with Claire and the boys. Car ran absolutely faultlessly for first 230 miles then it lost power whilst in top gear on the A590 Cartmel by pass.
I pulled over and left it for a few minutes, restarted and it ran well for another 10 miles or so. This repeated five times until I arrived home. I have taken it out again since on a 20 mile spin and it was okay, nevertheless Claire's lost confidence and it's back in the garage for further investigation/set up- Hopefully it will be fully sorted this time!

[neil-yaj396]

Sounds like more dirt in the carbs. These faults are intermittent because the dirt gets in the jet channels, dislodges, but then gets sucked back in again. By dirt I mean something smaller than a grain of sand! Injection systems just blow crap like this straight through.

As above this was pretty much the story with my Beta which had not had a good run for many years before I bought it. The only 100% cure is a full strip down and into one of those ultrasonic cleaners.

On the other hand my car was eventually cured without this by regular filter changes and doses of Redex.

[lancialulu]

Paul

Check your fuel filters as they may be blocking from crap in the tank. Happend to Brian Mills and his new acquistion until he had got through a few filters....always the same when cars have not been used regularly condesation causes the tank to gently rust from the top down and generates a sandy dust confused with poor petrol but its rust....

Amend this as just seen your other tank refurb post, but still worth checking

[stanley sweet]

I now run standard 42 solexs on standard jetting on my 1600 Sport. I had an odd hesitation sensation every time I wanted to accelerate from a cruising rpm of 4000ish. The car would hesitate for less than a second then had good acceleration afterwards. Tried all sorts to cure and resigned to live with it thinking maybe the Holbay tuned head and cams were to blame (timing spot on). Then late last year I splashed out on an Omicron Group 4 exhaust for the HF which freed up an Evolution Group 4 manifold which I retro fitted to the sport as the car had an exotic long header designed one off exhaust system. This had been designed by a previous owner to lift the max torque to motorway overtaking equivalent rpm. the only problem with this exhaust was it had to go under the subframe not through it. At least once a year it took a bash from uneven roads. Anyway the long and short of it is that the hesitation has gone!! Suspect the exhaust is so efficient a scavenging  the when the engine tried to accelerate the mix was momentarily too weak.

BTW I cant see how changing slow running jets can overcome poor performance at beyond slow running conditions.

BTW2 Anyone want a crazy Fulvia ss big bore manifold free to collect?

My 1300 now hesitates momentarily on hard acceleration then accelerates strongly. This is since I've run it on trumpets with filter socks. Never occurred with the original filter set up. Must be a similar thing - momentarily weak.

[lancialulu]

I wonder if Paul you have a condenser problem. I am reminded of our first rally in our restored 1600 Sport which was going well until it lost all power going through a Belgium Forest. I changed the distributor capacitor for a new one I was carrying, and the car started and never produced the same problem since. I have however reinstated the Luminition ignition system that came with car after returning to the UK, so have no way of know if it would happen again but 1000km it was fine. Epilogue - tested the old capacitor when I returned home and it had not failed (fully).....

[Paul Greenway]

Tim/Neil,

Thanks for your advice, I will pass on all info to my mechanical friend who hopefully will quickly establish & resolve the issue.

Cheers,

Paul

[rogerelias]

Sounds like an electrical problem to me, but hey what do I know  keep us posted Paul

[fay66]

only way I got over the fuel problem was to fit a filter King unit, the amount of crud that it stopped getting to the carbs had to be seen to believed

Brian
8227

[Paul Greenway]

Roger,

Your'e not the first one to suggest it may be electrically related.

Brian,

I had a Malpassi filter King fitted a couple of weeks back at the same time as the new pump.

Hoping to know more about the problem tomorrow. Will keep all posted of developments.

Cheers,

Paul.