Loss of power and stopped after drive hard to start

[gimli497N]

Hi All,
I'm new had my splitty for a year now its been fine.. Last night driving it home from work.. It drove to work fine early in the morning. It was quite a hot day.. After about 10 mins and a bit of sitting in traffic started up a slight hill.. She started to lose power and miss if i floored the throttle she would pick up a bit and keep going then lose power again and eventually die. After sitting for 10 mins she started again drove for about 5mins again and then died and would not start. I managed to get off the road and sit for about an hour then she drove for about 10 - 15 mins and then same again.

Now while i was sitting i found that the distributor clamp ring was loose as the bolt thread had stripped . Managed to use another nut to get it to tighten and retimed it. I got it running but again it did it again after 5 mins driving.

Some back ground over the weekend i gave the van a full service including the valve clearance's. The engine in the van is a reconditioned one that came with her when i bought her. In the documentation that came with the engine it said the clearance's should be .20mm but the book How to keep your VW alive says it should be .15mm i set them to the book .15mm.

Also while sitting i looked at the fan and found a plastic bag which i removed. I dont think she over heated though as i have a Gene berg Dipstick temp sensor and it never set the light off at all. SO my question is where do i start its got plenty of spark and it idles and revs fine.. Its just after driving for a few mins. I just dont know where to start. Please help.

Thanks

[pom2ter]

had same issue on hot day , this was the coil ... maybe you can look at this ... loss of power , hard to start when hot ...

[LAGrunthaner]

pom2ter good call.

[pondoras box]

Check fuel line routing if it touches anything hot it could vapor lock on a hot day. Next question is do you have a stock fuel pump or electric one, if an electric one goes bad the first indication will be exactly what you described.
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[gimli497N]

You know the coil never even crossed my mind... silly its an obvious thing.. I did notice when i changed the plugs one seems to have not been firing and when i pulled the lead of to check after tuning the spark from the plug lead to the tip was yellow... which if memory serves is a weak spark, but at the time she was firing on all 4's and revving fine. Great video i will check to see if it is! Easy fix if it is though. Thanks

[Eric&Barb]

[BonTonRoulet]

I'm not signing up for bad spark or ignition problem therapy just yet. I'm going with the fuel side of things, namely the fuel tank not properly venting. Take the fuel cap off and go for a drive. See if it gives you the same problem in the same typical amount of time. Or else drive around again like you have been and when it quits go see if you can loosen and remove the fuel cap without pulling against a vacuum and hearing a big "whoosh" when you loosen and remove the cap.

IF the fuel tank isn't properly venting then the vacuum build up in the tank will be greater than the fuel pump can overcome and your engine will quit due to fuel starvation.

Good Luck!
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Never argue with an Idiot. They'll only bring you down to their level and beat you with experience.

[gimli497N]

Hi All,
Thanks for your replies... SO..... I checked the coil, as per the video and it seemed fine.. however i had a spare bran new one in the van... SO i swapped it out... I have just driven her home from my brothers place which is a 30 min journey its about 21C here at the moment. There plenty of hills and also traffic lights etc. She never missed a beat.. SO thank you so much for the advice. I have also checked the vent on the tank and that is fine, no fuel lines are touching anything hot however i have noticed the in line filter needs doing which i already have one ready so i will do that later.

One thing i would like to ask in addition is what is the normal running temp for these engines because i can never tell. The gene berg dipstick when i pulled up at home, was about 2 thirds the way round to the screw. I have an infa red thermometer and with her sitting at idle (after the 30 min run) the heads were showing about 250F. Also with regards to timing. I am running a 009 distributor its currently timed at about 29 degrees BTDC at max advance she seems happy at that. I tend to use a light to time it at max and let the idle fall where it may as i know not all 009s are the same etc. The dwell is currently sitting at 48 degress which according to the book is within tolerance. Does all this sound good to you guys? Any suggestions?

Thanks Again for the replies though i really appreciate it!