5K Questions! Won't idle, threads merged.

[5ksev]

hey all,

 

iv got a 5k with 32/36 weber? ( i think )

tighe 25/65 cam

10:1 compression

premium 98 fuel

 

i got it all back together today, and it was running fine for about an hour, i turned if off, to put a stronger spring on the throttle return, and didnt like it so i put the old one on again.. started it up, and then all of a sudden it just wouldnt idle.. it kept stalling.. so i turned the throttle up, and it will idle at around 1200+rpm, but if i slow it down to about 800-1000 it runs for about 5sec, then gets real rough and stalls..

 

is this because of:

 

• 
   
  
• carby needing to be tuned?
  
• timing is wrong?
  
• or my dizzy needs to be adjusted?
  

 

video of it idling alright

 

http://youtu.be/tply9tZh2EU

[SLO-030]

Dude, please consider making a rides thread and put all updates/questions in there. 6 threads on the first page alone.

 

Cheers :)

[5ksev]

Dude, please consider making a rides thread and put all updates/questions in there. 6 threads on the first page alone.

 

Cheers :)

no idea how to do that but yeah.. sorry about all the threads.. i just keep coming across problems!! hopefully this will be the last one.

[Trev]

Did you bed in the cam?

[5ksev]

sure did, my mate ( performance mechanic ) said to run it for an hour or so, over different rpm's

[Trev]

ok, what is his opinion on it then?

 

Go over and recheck the valve clearances.

[5ksev]

i havnt spoken about it to him yet, as its a bit late..

 

how do i go by checking the clearances?

[Trev]

I don't know the value but you need to go over and check them with feeler gauges and adjust accordingly, how did you set it up prior to this?

[5ksev]

I didn't, I just took my head off and got a place in town to shave it. And put hd valve springs in.. I don't understand how I adjust the valves though?

[Trev]

Oh, well I would say that there is your problem, when it heats up the gap closes, the valve was most likely pushed open a little bit and it didn't like to run at low rpm.

 

Adjust them and I bet it will be fine.

[Figjam14]

pretty sure there set at sixteen thou

[Trev]

Did a search around and this is the best I can find:

 

 

Valve Clearance

 

Hot

IN; 0.20mm, 0.008in.

EX; 0.30mm, 0.012in.

 

Cold

IN; 0.13mm, 0.005in.

EX; 0.23mm, 0.009in.

[Evan G]

blocked idle curcit

[altezzaclub]

blocked idle curcit

 

X2

 

Trev could be right, but that is pretty esoteric. You would need the tappets set at under 2thou as they only grow 3thou between cold and hot.

 

Clean the idle jet and blow out the idle circuit in the carb. Evan can help, he has had his apart a zillion times! :laff:

[altezzaclub]

Arrrgh! 5K ! Hydraulic tappets... You don't set them.

 

Much more likely to be carb than anything else in that case.