Age old questions, but please do read.... loss of power etc

[davidvincent]

Hi John

Thanks for that, I'll get a good look at those parts tomorrow and see what what

Thanks for the tip!

Dave

[BOXY]

Another thing to check is that the two nuts holding each carb to the manifold are tight and the gasket hasn't split or cracked. Whilst there check around both carbs to make sure all the solenoid electrical connections are clean and tight, and the solenoids themselves are all screwed tightly into the carbs.

[davidvincent]

Have you changed the black T bit below left carb to servo and L pipe below right carb? I know they may look ok but Kev told me to change anyway and when I took them off the underside had cracks. Just an idea mate, hope you get sorted.

John

Hi John

I found one split hose on the left and have replaced but unfortunately no major improvements, still stalling.

Thanks for the tip though mate, I'll keep on looking!

Dave

[davidvincent]

Another thing to check is that the two nuts holding each carb to the manifold are tight and the gasket hasn't split or cracked. Whilst there check around both carbs to make sure all the solenoid electrical connections are clean and tight, and the solenoids themselves are all screwed tightly into the carbs.

Hello there - the nuts on each carb are secure, managed to get less than a quater turn extra on each only.

The gaskets look okay but then it's tricky to really see.

All connectors had had a little clean up and are connected well, as are the solenoids.

Unfortunately no major changes to the running of the engine here, thank you for the advise though, feel free to throw any other tips my way!

Cheers
Dave

[CovKid]

Ok, providing compression is good on all four cylinders (and you need a gauge to check that), idle relies on an airtight system up to carb throat, as does low speed. Under load, petrol is being squirted down carb throat but below this the engine likes a measured and predictable dose of fuel and air and on the 2.0 its a balanced system (effectively one carb split in two). Any imperfections such as air getting in via throttle flap shafts (the lower ones) will cause stalling at junctions and rotten idling. Same applies to gaskets underneath carbs and the ones where inlet pipes meet cylinder heads. Clogged fuel filter or air leaks in fuel inlet line also mess up idling.

Incorrectly functioning chokes might be a possibility as could worn points if you don't have electronic dizzy.

Spraying WD40 around carb gaskets, flap spindles, hoses and inlet gaskets may just help you find any obvious leak as it'll start to run properly whilst leak is temporarily plugged. Thats if it is fuel related....

Myself I'd go AA style and get compression readings as a baseline then work through each system accordingly.

[Steve T]

I've read all the post and think it is deffo fuel or mixture related

£50 fuel is more than it has had in it for a while, has this extra / more than usual stirred sediment that has been dormant in the tank.

Try running without fuel cap to eliminate vacuum in the fuel tank (preventing fuel delivery) check breathers not blocked.

Have you checked fuel delivery (outlet) from pump, Crank engine over with fuel pipe in container, but take care don't spray fuel everywhere if no fuel or small amount, is pushrod bent, is the fulcrum pin of fuel pump actually working and in place, is that where you oil leak came from, I had problem a while ago where fulcrum pin was dropped in one side and sticking out the other side preventing pump from operating correctly.

Assuming the fuel is clean and fuel filter is working no hole that has allowed dirty fuel into float jet and partially blocked inlet to carb, preventing correct level in carb, have you looked in carb bowl to see if there is any water / muck in there

Have you checked the vacuum advance on the dizzy (suck on the air pipe and check it moves)

Has timing slipped by small amount

Hope this gives you some more things to eliminate and sort you problem
Steve

[davidvincent]

Thanks for these tips guys.... urgh I need to do some reading as a few of the checks are on the advanced side for me, but I will definitely get stuck in and get to the bottom of it - thanks again.

[davidvincent]

Try running without fuel cap to eliminate vacuum in the fuel tank (preventing fuel delivery) check breathers not blocked.
Steve

Hi Steve

Right I'm back after a house move (the poor van limped weakly) and now getting back on with this problem.

I tried running with no fuel cap and found no difference, still stalling and not idling... presume that on the road power would still be lacking.

I've also replaced the manifold T-piece which someone else recommended changing earlier, no change.

Steve could you advise me on your comment above "check the breathers aren't blocked"? I should know what the breathers are but...

I did notice that the filler pipe is corroding and there's a section where I can see day light through - I guess this will allow dirt and water in over time... hhm, any thoughts?

Dave

[Mickyfin]

Sounds like a blocked fuel jet in one of your carbs to me, possibly no completely blocked, but possibly a odd shaped small foreign body which moves now and again, changing the quality of performance if that makes any sense? I have had similar on an old car of mine, and replacing the carb jets resolved it for me.

Another possibility is your compression, get yours checked before going on any further would be advised.

[billybigspud]

i spent £100 on mine at a local specialist and it now runs like a dream. just spend the money and get it done properly. mine was running like an absolute bag, 5mph hour up hills if it didnt stall half way up, constant backfiring, no power even on the flat, worse when i was loaded up. everything pointed to lack of fuel and it was but was adjusted through the correct timing and carb set up. new vacuum hoses as well ( still got to put up a pic of this as it is very unusual ). like i said, just spend the dosh and there is no harm in asking what they have done afterwards and why so you know for next time.

[davidvincent]

Sounds like a blocked fuel jet in one of your carbs to me, possibly no completely blocked, but possibly a odd shaped small foreign body which moves now and again, changing the quality of performance if that makes any sense? I have had similar on an old car of mine, and replacing the carb jets resolved it for me.

Another possibility is your compression, get yours checked before going on any further would be advised.

Hei Micky

Kiitos... I'll look into that, sounds promising

Moikka
David

P.S. My girlfriend is from Turku, Finland... hence the lame attempt at the language in this reply!

[Mickyfin]

My wife is Finnish Dave, Im English, Originally from the UK, but I escaped!

[HarryMann]

and replacing the carb jets resolved it for me.

Blocked jets, there's always been a remedy if its dirt or a drop of water, not really any need to change them...

Quick clear: Using a strongly gloved hand, rev the engine on the butterfly levers with the air cleaners off, and as soon as the revs start climbing, whack flat of hand over carb mouth until revs drop back and she chokes up, removing hand, to just keep engine running. Slap hand over carbs at different throttle openings, waiting till it gets up on top the 2nd choke main jet finally. Ditto other carb...
This is an old trick to suck any rubbish through the jet and if nothing else, upsets any muck and gives it a chance to find a way out.

Alternately, dismantle clean/clear: remove carb top plates and wash, blow out or vacuum out muck at bottom of main jet and emulsifier tube wells. Alt remove same (jets & emulsifier tubes) and clean by inspection. Replace carefully, do not 'graunch' slots as jets are brass!

[HarryMann]

http://archive.club8090.co.uk/viewtopic ... 2&t=36598&

https://club8090.co.uk/wiki/Fu ... ocked_jets

[davidvincent]

and replacing the carb jets resolved it for me.

Blocked jets, there's always been a remedy if its dirt or a drop of water, not really any need to change them...

Quick clear: Using a strongly gloved hand, rev the engine on the butterfly levers with the air cleaners off, and as soon as the revs start climbing, whack flat of hand over carb mouth until revs drop back and she chokes up, removing hand, to just keep engine running. Slap hand over carbs at different throttle openings, waiting till it gets up on top the 2nd choke main jet finally. Ditto other carb...
This is an old trick to suck any rubbish through the jet and if nothing else, upsets any muck and gives it a chance to find a way out.

Alternately, dismantle clean/clear: remove carb top plates and wash, blow out or vacuum out muck at bottom of main jet and emulsifier tube wells. Alt remove same (jets & emulsifier tubes) and clean by inspection. Replace carefully, do not 'graunch' slots as jets are brass!

Harry - I've run through the quick clear process quite thoroughly and found that by doing so I can get to a nice steady idle, I can even get to the end of the road with decent power and smooth revs, then it returns quickly to the stuttering and stalling.

I went through this twice, made it good, took a sort run on the flat and limped back home.

So, in your experience would this lead you to think that the jets are the culprit here and that I'm perhaps only just moving the dirt or whatever is lodged around temporarily? If so would next move be the dismantle clean and clear procedure?

I've not had the carbs off myself before so this would be a challenge, which is good/fine. I did have the carbs tuned and serviced about 2 years ago at southern carburettors.


Thanks again all.
Dave