Author Topic: Timing issue!!!  (Read 2973 times)

Offline josh0325

  • Newbie
  • Posts: 36
  • Newbie
Timing issue!!!
« on: September 25, 2017, 08:08:17 PM »
Finally got valves adjusted, and the engine is running much better, but when I'm trying to time it with vacuum advance disconnected, the timing mark is bouncing back and forth on the pointer.  The harmonic balancer has not slipped, and timing set is brand new. Spark plugs wires, and plugs are new too.  I've never seen this before, Vacuum canister seems to be too advanced, but mark is fluctuating between 10-14 degrees BTDC.  If I retard it, it doesn't even register on the timing gun dial, and it runs like crap


Sent from my XT1585 using Tapatalk


Offline bd

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 6438
Re: Timing issue!!!
« Reply #1 on: September 25, 2017, 08:36:14 PM »
Try moving the inductive pickup to a different location on the #1 wire.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline FlatBlack77

  • Junior Member
  • ***
  • Posts: 894
  • Cheap Fast Reliable - Pick 2
Re: Timing issue!!!
« Reply #2 on: September 25, 2017, 10:20:18 PM »
are you plugging the hose for the vac advance?
"When you are a hammer, everything looks like a nail"
'77 C/10 - 350/350 mild street motor

Offline josh0325

  • Newbie
  • Posts: 36
  • Newbie
Re: Timing issue!!!
« Reply #3 on: September 26, 2017, 08:13:06 PM »
I have moved the inductive pickup all along #1 wire to make sure spark wasn't jumping between wires, and I only plugged the vacuum canister at the carburetor.  I didn't think I needed to block it at the vacuum advance as well.  The canister just seems to be too close to the T fitting on the intake manifold for the vacuum modulator, and power brakes.  It is almost pointing straight ahead towards the carburetor.  I'm going to purchase a new dizzy from proform that's already been curved to match my engines performance.

Sent from my XT1585 using Tapatalk


Offline FlatBlack77

  • Junior Member
  • ***
  • Posts: 894
  • Cheap Fast Reliable - Pick 2
Re: Timing issue!!!
« Reply #4 on: September 26, 2017, 10:29:56 PM »
yeah you just need to plug the line coming from the vacuum source i should have been more specific.

it sounds like your distributor is turned pretty far
"When you are a hammer, everything looks like a nail"
'77 C/10 - 350/350 mild street motor

Offline VileZambonie

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 18979
Re: Timing issue!!!
« Reply #5 on: September 27, 2017, 05:53:51 AM »
Dizzy's are for Honda's. If your vacuum advance diaphragm is pointing at the carburetor, you have it installed incorrectly. Move the distributor back a tooth and ensure the distributor is fully engaged and seated.
,                           ___ 
                         /  _ _ _\_
              ⌠¯¯¯¯¯'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline FlatBlack77

  • Junior Member
  • ***
  • Posts: 894
  • Cheap Fast Reliable - Pick 2
Re: Timing issue!!!
« Reply #6 on: September 27, 2017, 10:25:33 PM »
Dizzy's are for Honda's.

I didnt think anybody would get that so i didnt say anything lol
"When you are a hammer, everything looks like a nail"
'77 C/10 - 350/350 mild street motor

Offline SinisterC10

  • Newbie
  • Posts: 93
  • Newbie
Re: Timing issue!!!
« Reply #7 on: October 11, 2017, 09:40:33 PM »
Your timing is most likely bouncing around because the vacuum advance is trying to open at idle. Either lower your idle rpm’s a bit or limit the amount of advance in your distributor.

Offline VileZambonie

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 18979
Re: Timing issue!!!
« Reply #8 on: October 12, 2017, 05:17:07 PM »
Dizzy's are for Honda's.

I didnt think anybody would get that so i didnt say anything lol

 ;D
,                           ___ 
                         /  _ _ _\_
              ⌠¯¯¯¯¯'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10