Jenvey throttle body balance.

[Nigel Riches]

I spent a few hours in the garage today trying to get the poor idling sorted on the 2L Black top Zetec with Emerald ECU.

I went right back to the very first steps IAW jenvey setup page, using a feeler guage under the butterfly plates set all to a gap of 0.05mm, with the cross link adjuster, all the air bleed screws were closed, and then I needed a tweak on the idle speed screw for the engine to run, a quick TPS realign and off it went.

I did find that the airbleed screws ware quite contaminated at the tips, this I removed, and then reinstated them from the positions removed.  

I have an airflow of 5Kg/hr through each intake at approx 1000 rpm, the engine is definitely more stable, gone is the shuddering and stumbling, and on snatching the throttle open it doesn't "gasp" and nearly stall.  

So my question is; 5Kg/hr sound like a reasonable figure  at idle, or do I need to revisit this, for more or less airflow.

Any thoughts or directions gratefully received.

Cheers.

Nigel.

[Molecular--Bob]

I wouldn't overthink it, if they are balanced at idle leave well alone. The transient / acceleration fueling may need looking at if it still stumbles on throttle opening. Do you have a wideband and the ability to log it's output? Not sure if the Emerald allows logging,but if it does you could see if it is going lean or rich during acceleration?

[Nigel Riches]

Thanks for the note Bob.

I don't have an O2 sensor, but it seemed to be running ok on the road test after the adjustments, not hesitating or stumbling, I have contacted an outfit in town, about a dyno run, but not got a reply yet.

Emerald does have a logging function, but I am a real techno numpty, and stuff like that just doesn't seem to work like says on the label.

Cheers anyway. 

[7 wonders of the world]

Did you disable the idle stabilisation on the Emerald first other wise you will end up chasing your tail...

There is a very good guide on the Emerald site, basically you turn this off, balance the airflows body to body, then fne tune with the bleeds and get a good base idle about 50 rpm below your ideal speed, 

[7 wonders of the world]

Here you go,

http://www.emeraldm3d.com/media/software-manuals/Emerald%20K6%20IACV%20&%20Cold%20start%20crib%20sheet.pdf

 

[Nigel Riches]

Thanks for the link, very helpful, I'll have a go after taking my next brave pill, as I am completely adrift with this stuff, so the nice easy step by step text is much appreciated.

Fortunately the old Black head engine doesn't have an IACV, so one less thing to factor in.

I had another play about this morning, there has been an improvement in starting but it is still on the low RPM side, until warmed up. 

Oh well, bash on, I hope it will start better after the wash and polish  

Cheers.

Nigel.

[oilyhands]

I would be aiming for 5.5kg/hr+ or your cold start will definitely struggle, at 5kg/hr the advance will need to ramp up significantly when cold to maintain idle. On an 1800K series I aim for 5.5kg/hr and this consistently gives perfect idle when hot and reasonable cold start, this is over around 200 engines with TBs/Emerald. Fuelling has a large part to play in cold starting...

Oily

[Nigel Riches]

Thanks Oily, seems like something to do later when it's not raining. .

The bloke from the dyno outfit called yesterday and said that he has some experience with Emerald ECUs and as it is in a running state shouldn't be too far out of whack, so just need to get a W O F (MOT) and make a booking, things are moving forward again.  just in time for the summer to fizzle out.

Cheers.

Nigel.