bad idle, no throttle response
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bad idle, no throttle response
I just installed a new summit mild cam, gear drive, lifters and 390 springs. when I start it it runs rough, shakes and occasionally backfires. i have the timing set at TDC for what I can see, when I installed the cam I had the "0"s on the gears facing eachother. Im at a loss and am extremly frustrated. anyone have any ideas?
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Logistics Pro
Joined: Jan 2007
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From: Martinsburg, WV
The balancer is made up of two peices, the hub and outer ring. they are joined by a rubber ring. it is common for an older balancer to have the outer ring slip. Ypu need to pull #1 plug and verify tdc and see where the balancer mark is.
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From: Denver Metro Area, CO
Although, when I've encountered that situation myself, twisting the distributor in a way to adjust the timing makes a helluva difference in how the engine runs (and how it stops running, generally accompanied with a puff of what looks like jet engine exhaust emanating from the carburetor).
If there is no confusion here as to terms used to describe components, and it is true that turning the distributor with the engine running results in no perceivable change in the engine's running characteristics, then something is big-time wrong here.
Well, wait - all the way to one extreme results in more backfiring... if that's the case, then go the other way. I would pull the dizzy and install it one tooth offset so that the rotor can continue turning in that "other direction."
There is quite a wide variance of space where the rotor "appears to be correctly oriented" when in fact it's not.
The following may help you see that somewhat:
Ford Fuel Injection » Setting the timing
Cargo Master
Joined: Oct 2005
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From: NJ
Ballpark your timing at TDC to get it running, then set to 10* initial. Adjust your carb idle mixture and you should be good. Good idea to check your float level too, just to be sure. Check for vacuum leaks as well. Are you sure you adjusted the valves correctly? If non adjustable (you likely have non adjustable pedestal rockers) how much preload do you have?
How did breakin go? Any issues with temperature or leaks? What oil did you use and did you use an additive?
How did breakin go? Any issues with temperature or leaks? What oil did you use and did you use an additive?
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ok, so i re timed the timing gears at 2* advance, it runs decent now till I give it throttle. I have no break in time, just got it installed. I am using 15-40 rotella T to break it in which has a great amount of zddp. how do you set pre load? I have pedestal rockers. I was told to tighten the rocker bolts to 28# and call it good. no temperature spikes yet. it seems to only like to run well with the choke pulled, but like i said once i give it gas it dies most of the time.
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From: Denver Metro Area, CO
10° BTDC is the best initial starting point, I urge you to start there.
I don't remember the details of your engine but if you've got a flat-tappet cam you should really be following the manufacturer's assembly & break-in instructions which are going to be quite explicit about moly-based assembly lube, break-in oil to use, length of time and at what RPM to run the engine at break-in, and zinc content in future oil.
I don't remember the details of your engine but if you've got a flat-tappet cam you should really be following the manufacturer's assembly & break-in instructions which are going to be quite explicit about moly-based assembly lube, break-in oil to use, length of time and at what RPM to run the engine at break-in, and zinc content in future oil.