I have had this 1978 cruiser with 2F engine about a month. I tackled an emergency brake rebuild first since it wasn't working at all (thanks all for the help) . Changed the fluids. Next up has been a tune up. Bought the tune up kit from JT outfitters before I read all the bad posts about them and that I probably should have ordered OEM stuff from Cruiser Dan. They did send me the wrong distributor cap though ( i originally ordered a 1977 because my build date was 12/77 but thought they had changed it out). Bought an OEM cap from SOR. So now on to changing plugs, wires, and dizzy cap. I am definitely new to wrenching so I decided to try out my new timing light before removing anything. Found the timing mark bb and painted it white. When I shoot the light at it from the passenger fender side the bb seems to bounce around sometimes before, on , or after the bb. Thought it might be because the plug wire were a tangle and old so I went ahead and pulled the wires and cap off and pulled the old plugs. Pictures are of my timing mark in the window #1, my dizzy cap #2 (broken ventilation port by me).
timing mark moving around at idle
- Thread starter AlaCruz
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Are you checking timing @ the correct idle speed and vacuum lines plugged?
- Thread starter
- #3
I've been reading on MUD for weeks, have the FSM and a Haynes.
So my questions are:
#1Any ideas on why the timing mark is bouncing around?
#2 While changing out the plugs all came out easily but one plug will not easily thread by hand so I assume must be cross-threaded. I searched online and found options of heli-coil or something called a back tap. Sears carried one for $75 but i found one on Ebay for $16. Has anyone used one of these? Any other ideas?
#3 The Bosch plug wires I bought are not loomed, how should i do this?
#4 when using a compression tester and after disconnecting the line from the coil do i need to ground that line or just let it hang?
So my questions are:
#1Any ideas on why the timing mark is bouncing around?
#2 While changing out the plugs all came out easily but one plug will not easily thread by hand so I assume must be cross-threaded. I searched online and found options of heli-coil or something called a back tap. Sears carried one for $75 but i found one on Ebay for $16. Has anyone used one of these? Any other ideas?
#3 The Bosch plug wires I bought are not loomed, how should i do this?
#4 when using a compression tester and after disconnecting the line from the coil do i need to ground that line or just let it hang?
- Thread starter
- #4
My idle speed is between 670 and 700 rpm. I disconnected the two vacuum lines to the distributor and plugged both with bolts. I should say that while going over the truck just to see what I have i've found that a po had done a half-baked desmog. There are several lines just hanging loose and some are capped. I'm reading up on the emissions manual now.
- Thread starter
- #5
By the way, I noticed my thread is not marked as NEW. How do I make this happen when starting a thread?
Its marked NEW for each person when they see it... since its your thread it won't be NEW to you after you post.
The timing mark jumping around a bit is not unusual. It can be caused by wear and play in the shaft bearings, cam gear, centrifugal advance and vacuum advance plate. As long as it doesn't prevent you from setting the timing properly and the engine runs fine, don't worry about it. It is not likely to be bad shaft bearings with the large cap electronic distributor.
Idle must be set to 650-700 rpm. I've had the same issue when tuning my 2F. Plug all vac. lines and try your best. I would got back and then adjust your carb to max vac at idle. then check you timing again, it's a little game but trust me it makes a difference overall in the end with smooth idle. I can idle at 500 rpm and crawl smoothly. I would also seriously consider checing your valve lash at this time too. do it after everything else! do it hot.
