Home 
Home Search search Menu menu Not logged in - Login | Register

 Moderated by: Greg Fletcher
New Topic Reply Printer Friendly
running rough  Rating:  Rating
AuthorPost
 Posted: 06-16-2006 03:20 pm
  PM Quote Reply
1st Post
Ian Brooks
Member
 

Joined: 05-16-2006
Location:  
Posts: 11
Status: 
Offline
Hi all,newbie here.

Bought my JH a month ago & she ran fine,however last week after firing her up sounded like she was running on 2 cylinders,so replaced plugs & wires to no avail,then pulled the distributor to find the vacuum advance piece was broken & un repairable & the iwires were looking a bit dodgy ,so ordered the petronix & flame thrower coil.Installed those & bypassed the resistor & gapped the plugs to 45,still to no avail.Pulled one of the carbs to find the real problem all along, a blocked main jet,so cleaned that & got it to run on all 4.However stiil wasnt running smooth like she did.Put a timing light on it to find it was way advanced so tried to retard it only to find the vacuum advance was hitting the block,so proceeded to loosen the timing belt taking care to keep belt tight on cam shaft gears.Finally was able to retard timing to 8 degrees,but she sounds terrible.Getting really frustrated now,pulled & cleaned plugs,leaned out carbs as plugs were sooty & smoke coming out of tail pipe.This is a rebuilt engine by the way or so I was told when purchased .did a compression test & she read 115-120 all the way across.]

Not sure if this is a spark or fuel  problem,any suggestion or clues would be greatly appreciated.Thanks in advance,Ian

 

 

Back To Top PM Quote Reply  

 Posted: 06-16-2006 03:59 pm
  PM Quote Reply
2nd Post
Mitch Ware
Member


Joined: 03-12-2005
Location: Albany, New York USA
Posts: 204
Status: 
Offline
A couple of things stand out, IIRC your plug gap should be 35 not 45. Also with pertronix timing should be 12^ advance.

Back To Top PM Quote Reply

 Posted: 06-16-2006 05:14 pm
  PM Quote Reply
3rd Post
John Kimbrough
Member
 

Joined: 03-12-2005
Location: Washington USA
Posts: 116
Status: 
Offline
Ian, you might also want to try putting that balast resistor back in.  I put in a pertronix, left the resistor in, and it is running fine.  You might be shorting out somewhere because of too much spark.  John. 

Back To Top PM Quote Reply  

 Posted: 06-19-2006 04:14 am
  PM Quote Reply
4th Post
Ian Brooks
Member
 

Joined: 05-16-2006
Location:  
Posts: 11
Status: 
Offline
Thanks for the tips guys will advance the timing & reduce the gap.It definitely runs smoother the more advanced I go.Pulled the carbs & retightened them evenly as was sucking air somewhere ,it does,nt change rpms now when I squirt carb cleaner & that made a big difference.I still think I need to lean the mixture a little as the plugs are little sooty.Seem to be making progress though.

Ian

Back To Top PM Quote Reply

Current time is 09:36 pm  
> Jensen Healey & Jensen GT Tech > Ignition > running rough Top




UltraBB 1.172 Copyright © 2007-2011 Data 1 Systems