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Topic: High rpm when cold for 20 minutes,...?  (Read 166 times) previous topic - next topic

Re: High rpm when cold for 20 minutes,...?

Reply #15 –
Quote from: philip on
yes sorry i did test the coolant hoses and they are getting hot. I was just about to ask if it was worth it to take it out and do the boiling water test in the hope of a miracle or improvement,...lol. I will do this over the weekend as at the moment weather here south east not the best,...If i remember well, I only have to take the air filter housing off to get easy access ? thanks again, fingers crossed as this problem just suddently started 6 months ago.
Yeah, just remove the airfilter and disconnect the hoses at the choke and the coolant pipe.  On the video I mention how many milimetres (cant remember) its supposed to stick out when its fully heated up.  I did my own one using this method.  Sadly a year later it started to leak.  Finding one in good condition is tricky.

Re: High rpm when cold for 20 minutes,...?

Reply #16 –
Quote from: philip on
and i forgot, i looked at the 3 point unit, there is no gap what so ever cold, or hot,...
That's odd, should be a gap when its cold and the waxstat is keeping the throttle arm from touching it.

Re: High rpm when cold for 20 minutes,...?

Reply #17 –
Well, I don't know how to explain this, may be the weather being so hot? I was up at 8 am down to the car all ready for the mission lol.
When i took off everything, i realised i didn't have the right tools to take of the waxstat. I then remembered that 20 years ago ( i got my golf from new ). I actually fiddled with the settings of the cab flap, sucking on the hostpipe turning that wheel,....So i thought, let's check the gap again that should be around 2.5 mm. It was way off ! No wonder i've been using over 12 liters of petrol per 100 K for years when it should be around 9.5 L max urban ( that's all i do ). So to make a long story short, i adjusted it as it should and then lightly gave a few hammer hits on the waxstat ( yes i know, pretty stupid ). In any case, put everything back, started the car, it idled at 1100 rpm, drove 5 minutes, when straight back to 850/900 rpm ? Must be a miracle ! But i will not know until tomorrow morning when it's stoned cold again if this did the trick ! Fingers crossed, Un-real !!!

Re: High rpm when cold for 20 minutes,...?

Reply #18 –
Hi, well it's bizzare, tested the car this morning, idles at 1100 rpm for 15 minutes then goes back around 900. After leaving it to cool down an hour, it starts and idles way too low at +- 600 rpm for about 10 minutes. I think i'm going to leave it be now and stop fiddling as there is a big improvement in any case. Thank you all for all the help and especially the video you sent me that was so usefull to learn about the cab,... the old girl got 89000 miles, first owner from new. I wanted the GTI but couldn't afford it so got the last 1600 cc Driver without power stearing lol.

Thanks again,

Phil.

Re: High rpm when cold for 20 minutes,...?

Reply #19 –
Quote from: philip on
Hi, well it's bizzare, tested the car this morning, idles at 1100 rpm for 15 minutes then goes back around 900. After leaving it to cool down an hour, it starts and idles way too low at +- 600 rpm for about 10 minutes. I think i'm going to leave it be now and stop fiddling as there is a big improvement in any case. Thank you all for all the help and especially the video you sent me that was so usefull to learn about the cab,... the old girl got 89000 miles, first owner from new. I wanted the GTI but couldn't afford it so got the last 1600 cc Driver without power stearing lol.

Thanks again,

Phil.
Glad you found the video useful.  There is so little info on these carbs, and it took me a while to figure out how it worked, so I wanted to share the knowledge.  Its fair to say the carbs are rather over engineered, and not particularly resilient.  I had a 1990 Toyota Carina for 7 years, before I bought the 91 Driver.  The Toyota had a carb that worked so well from cold it used to surprise me that it didn't have fuel injection.  It was flawless.  It makes you wonder if the japanese could design a carb to work so perfectly, why cant the europeans!!

At the moment I'm running the supposedly better Weber.  Its not true.  Its better than a knackered Pierburg, but its a crude carb which cant deliver the fuel efficient running the pierburg can deliver.  I've done another video on it.  Its flaw, in the 1600, is the accellerator pump jet.  The web con kit has the same jet for the 1600 and 1800.  Why?  Because its the smallest one they do.  It mean it delivers too much fuel when you floor the throttle, cause it to stumble before it accellerates.  It can also cause the engine to stall at idle if you blip the throttle.  I have managed to improve it though.  There is an external arm/cam wheel, that controls the amount of fuel.  I used a dremmel to take 1mm off the cam which has the effect of reducing the amount if fuel the pump jet delivers.  Its a lot better, but its still a little on the rich side, but it does the job.  Its also harder to start from a warm start, as the idle and the choke are controlled both by the choke cable, and the idle only increase when you pull the choke out most of the way, i.e too much when warm.

Re: High rpm when cold for 20 minutes,...?

Reply #20 –
It's obvioues to me that you know your stuff ! I've been trying to learn for the last 30 years about these cars doing my best. Your knowleged is a credit to this website and i can't thank you enaugh for everything. I have been looking for years for video's like you sent me and never found one that informative ! I hope my golf will keep going for as long as possible, i do get a lot of attention now adays with people beeping, flashing there lights, thumbs up,...that i never expected. Thanks again, until next time lol