Push loud pedal and engine stalls?

[jtbo]

Got this odd symptom after car stood over winter.

Car idles rather ok, I did need to rise idle a bit as after running minute or bit less idle speed seem to decrease, when I push throttle a bit it will pick up to normal again, this is not big issue.

Other thing however is bit bigger issue, when car idles and kick loud pedal to half way quite hastly it sputs and revs drop to 100 or so and engine turns very difficultly, if I pump throttle it can pick up again.

When I rise rpm to around 2000 very gently pushing pedal and kick loud pedal half way again it does the very same thing.

If car idles and I slowly apply throttle, around similar speed as normally accelerating in city car sputters and backfires, again if I pump throttle a bit it picks up rpm and around 3000 or more it seem to be running fine again or at least sputters less.

Perhaps this is caused because I do have wrong emulsion tube in 1st throat place, there is two of second throat emulsion tubes installed at the moment, I will swap that tomorrow so perhaps issue goes away, however I don't remember there being such issue at late summer/early autumn when car did run last time.

Also shouldn't that make it to run just quite rich?

Well, we see what happens tomorrow if there is no rain.

I did check oil and all looked to be okay, but after piston slap (I have quite bit of this) started to go away as engine did warm there was this thunk thunk thunk, which is imo crankshaft bearings, there was oil pressure as light was not lit and that did go away after engine was completely warm, don't know how hard that can be until need to worry but it was bit like gently tapping block with hammer, but sound was more soft like crankshaft bearing do sound.

225 000 km driven, can't need new lump yet or someone has fiddled my car's odometer before I got it

[Chris_C]

Could be a blockage on the second jet, then one that picks up when the butterfly goes past around 10degrees. Other than that, does the 200K carb have a full throttle pump thingy? Diapraghm could be split in that too, definately sounds like it is underfueling when you kick it.

[petefarrell360]

Just as a thought, how old is the petrol? Modern fuel really does deteriorate very quickly, and if there is a lot fo old fuel in there, then it won't be helping anything.

Pete

[jtbo]

Just as a thought, how old is the petrol? Modern fuel really does deteriorate very quickly, and if there is a lot fo old fuel in there, then it won't be helping anything.

Pete

Enough old, 8 months or so at least and there has been only very little maybe 5 liters in tank from autumn, ambient temps between -35C to +10C and sometimes way too much humidity

Must add bit more fuel even I did add fuel antifreeze so possible water will go and burn in engine instead of causing problems at tank end.

Diaphragm has to be ok, as it was ok and quite fresh at autumn when I had carb exploded and cleaned + fixed everything I could.

Old pertrol and emulsion tube are perhaps those that I fix tomorrow then and we see if problem persists.

[IvanS.]

After that long time it's possible that petrol lost it's octane number ( err....turned into water ).. Try adding more fuel or empty the tank, cose it might damage the engine.
Did you check the renix ( just a thought ) ? Might be electrical supply problem.

[jtbo]

Right, problem is mechanical, at end of 1st throttle plate shaft there is small metal part that actuates acceleration pump lever, now this part is perhaps worn as if I actuate accelerator pump manually same time as I open throttle wide there is no trouble.

Then I made small metal wire fix and now lever is perhaps 1mm further away from this worn part (metal wire in between them) and it works tad better.

Also found out that when engine is not running and as I play with accelerator pump fuel comes out from throttle plate shaft housing, so that should indicate that there is some wear in throttle plate shaft/housing too.

It always has had bit trouble with hesitation so there is answer for it, now as carb is more or less ok and not running stupidly rich all time this is just more clear problem than before.

Did not remember how loud my car was, must consider getting new exhaust for it at some point if I need to start driving more (that is if I get that job).

I do have spare parts carb, but I don't think that will help much of all as there is probably same wear and in that shafts are totally worn out, there is clearly some play, which is currently installed there is none or just tiny bit of play in shaft. Perhaps I can get some brass tube and possibly make some work to that older one so could then swap carb bodies to get nice and tight seal to there too.

There is still something wrong with my choke cable, I did found out that I had forgot retainer clip
So putting that back got it working bit better, now actually it moves lever, but I can't get it adjusted so that it would turn choke fully off, knob seem not to like to go fully closed position, when I pull it from carb side it moves last few mm but impossible to get this done from knob side.
I guess I need new cable after all, or maybe I try wd40 first, but can't see that helping for that last mm, it feels like something would get stuck or something like that.

Need to change insurance so I can actually hit the road, I get funny looks when revving at parking lot

[jtbo]

Did test drove it for 100km, damn there is something terribly wrong now:

Engine dies if..

..Choke is on and engine warm, when I put choke off engine rpm just drops so slow that it shuts down.

..Choke off, I blip throttle and it just sneezes, sputters and then stops gaining rpm and dies.

..Choke off, I pump pedal so rpm rises nicely I lift pedal up engine dies.

..Choke off, I drive normally around 2000rpm put clutch down and lift throttle, engine dies.

Engine sputters, shakes and gives lot of bangs and pops if I accelerate with around half throttle, full throttle is ok.

Sounds like a vacuum leak?

This is of course true reason why accelerator pump seemed not to squirt enough fuel, oh dear, lot to do again tomorrow

[jtbo]

That smaller ventilation hose was got itself out from plug that is below manifold, put it back and no help.

Got then idle mixture screw lost once again, damn thing is not staying on place at all, put another one in (always keep spare on car) and I have to adjust mixture screw so out that it fells out very easily, oddly enough that does not make big difference to idle.

I did install another set of seals to carb base and manifold side too, can't say any change at all, also there was no leaks that I could find after fixing that ventilation hose. Can't get it to run enough rich at low rpm area, can't be K-cam either as it can't draw so much more air.

Thermistor is next that I change, took thermistor lead out and at least at idle I could not find anything odd.

Oh and swapped emulsion tubes again, full throttle power is much less but part throttle is much better when it does not sputter and do all those weird banging and popping. Also finally understood which way those should be

I had bit this trouble last summer too, but got it to work bit better.

At least now engine does not die so easily, but if I hit brakes fast it tends to drop rpm quite a bit and makes running not so good.

I can drive rather ok if I keep choke bit on, but of course that is not too good solution.

Brake servo? Has anyone heard these been failing so that it causes air leak, but still working normally otherways ? It makes hissing sound and engine rpm is greatly influenced by brakes, but there is assist effect and it stays well after engine is shut off.

I don't know, maybe I just switch injection back in and hope that there is not any too tech interested cops that take out plates from car because it is injection instead of carb.

It drinks hell load of fuel at the moment, 21MPG mostly done on country roads (something relevant to b-roads I would guess) and I have tried to save fuel as much as possible, should get at least 30MPG, even k-cam, never exceed speed of 90kph and floored only once or twice. Of course if I try to use throttle normally, economical way it just sputters and pops, need to push it deeper and then back off to get it accelerating or slowing down bit less at hills, if I like to climb hill with constant speed I would need to almost floor it but then it jumps forward.

There would be 340 1979 Mk1 with manual transmission near for 250e, it is quite rusted and MOT is due, but started to interest after all these troubles where seem to be no logical conclusion, also if I find something is wrong I fix it and there just was no difference at all, still does not work, most frustrating.

[Chris_C]

Wasn't the whole reason you put it on squirt to get round this Jani

[jtbo]

Wasn't the whole reason you put it on squirt to get round this Jani

Yeah, it was. Well, maybe it is unavoidable and have to move again back to injection but it is soon again MOT time and need to take squirt out for mot, also that risk of getting caught running injection is something I don't like, to clear mot with injection it would cost again near 500 euros.

Can't think anything else so I try to make that other carb's base straight and put all good parts to that other carb's body, maybe there is some internal problem with currently installed carb then. Only problem in that is that throttle plate shaft has somewhat more play in that so I really doubt that to be any solution, but there seem to be no anything else left as I have rebuilt damn carb once already with good parts

Decent GLT is around 1000 euros and mint near 2000 euros here so bit expensive, but actually selling this one and getting GLT sounds nice, however would need carb working before that.

[jtbo]

Right then, now it is bit better again, but still not perfect, opened mixture screw a lot and put something to block it (currently bolt that has tape wrapped around so it is tight to hole) so that it cant unscrew and fall out as it has bit tendency to do then screwed one other screw fully in, it is number 2 in here http://www.janiervast.com/gallery2/disp ... um=8&pos=0 (click pic for bigger)

Now I need to apply only little choke to get it run fine without any sputtering etc. also without choke it runs better but lacks still loads of power so can't use 5th gear on road without choke.

I don't have a clue about fuel economy yet, I'm not hoping much more than 130km (80 miles) with 20 euros (equals around 12l/100km that is around 20mpg, 19.6mpg if we are specific) from highway...

[Chris_C]

Ouch Shame its causing so much hassle... whats up with the old carb? As an aside, there isn't any air leaks or blockages in any of the breathers are there mate?

[jtbo]

Ouch Shame its causing so much hassle... whats up with the old carb? As an aside, there isn't any air leaks or blockages in any of the breathers are there mate?

I did block that breather hose plug that is side of carb, that big one that goes top of carb to that plastic thing is normally there, so it can't get too much of air from there at least, hose on place there was not too much change, goes bit worse actually but not much.

Actually that one on place is still the old carb, this replacement one that I bought is so shot from throttle plate shaft that I think it would not solve anything.

So now there is no leaks that I can find, it just seem to get too much air when throttle plate is opened a bit.

After I did turn mixture screw as much open that is possible it really seem to idle much better and all, so I have been thinking to get this one extra idle mixture yet drilled bit bigger and perhaps that way I could make it run tad more rich so it would actually start working. Don't know how that would affect to fuel consumption, but I guess it can't get much worse.

[jtbo]

Right, I go and look for new screw driver (did broke tip from one, big chunk cracked out from it, China quality) that I can get main jet out and then I find small file and make it bit bigger, that should take care of problem for good.

[Chris_C]

File the jet? Surely its the holes in it that need to be bigger?