still not running right

[nkhd1]

rebuilt heads and now have good compression
rebuilt carb and then replaced it with another rebuilt carb
new coil, ballast resistor, reman'd dizzy,new plugs and wires (wires twice)
timing set at 12, replaced condenser and points - set gap at 17
vehicle rewired, battery replaced, metal fuel lines (checked it for leaks)

Still has a random put put sound when driving. sometimes causing it to stumble. can sometimes hear it when idling.

Vacuum gage hooked up to pcv hose vibrates between 19-21.
I don't have the git up and go that I would expect out of a 302 with 4:11 gears.

what have i missed?

 

[Nightstick]

Hmm, I'm no guru at engine diagnosis, but I figure I'll throw my $0.02 in since no one has responded yet... How bout the fuel pump? Has it been replaced? Sounds to me like either a fuel delivery or timing issue. Again, I'm no guru, just throwing ideas out there.

 

[broncnaz]

What voltage do you have at the coil when running? Should be around 8-9 volts usually could be higher.
How about the rest of the engine? has the timing chain been replaced? whats the oil pressure?
What tire size are you running?

 

[nkhd1]

The fuel pump was replaced. I checked all the fuel connections and bypassed the selector to rule that out.
I am getting 8v between the negative on the coil and the negative on the bat.
Oil pressure is OK. compressoin checked between 140-150
31x10.5-15 on the tire size.
Timing chain is an unknown. The PO told me someone had been through the motor - but i have since rebuilt the heads due to low compression in number 4. which has been corrected - and I have checked them all.
Thanks

 

[broncnaz]

Well the vacuum reading fluctationg between 19-21 still indicates valves issues. you may either have a stick valve or they werent seated properly. Of course it maight be a sticky lifter issue as well.

 

[nkhd1]

when we set the valves there was a lifter that was squirting oil a good distance- almost over the side of the bronco. My friend that was helping me said he had never seen that but it would not hurt anything.
If that could cause this issue then i reckon it needs changing.

 

[broncnaz]

I'd probably say that one was good. Maybe a little excessive squirting but you know its getting oil pressure. If you have some that are not squirting oil then they may be a issue. might be a good idea to check your valve adjustments if some are to tight that could be simliar to a sticky valve issue.

 

[nkhd1]

The other lifters were oiling fine - oil running over the rocker and dripping down the front of the rocker. Its just one was like a fire hose.

 

[broncnaz]

I guess that lifter could be stuck which could allow oil to pass directly through it constantly. but usually you'll start to get a ticking sound due to that lifter not functioning properly.

 

[red hot71]

Ditch the points they suck. Points should always be set with a dwell meter! If there's any contaminates on the feeler gauges they will cause early burning of the points.
Once you get a dwell meter hook it up and watch the meter running it should read between 25-30*. As a kid I use to fight setting the points,the ford distributors are not stable enought for points,again with a dwell meter at idle you should get between 25-30* now start increasing the RPM's and watch the dwell it will go bonkers (past 40+*)thats were your miss is coming from. You have a new distributor put in a pertronix conversion and be happy, and if you don't trust the pertronixs put your points into a plastic bag and put them in your glove box if needed.

If I remember right when dwell increses it means the point gap tightens up which causes timing to change,thats why the manfactures when to electronic it stabilized the most important part of the ignition system.

 

[knack]

12 degrees of timing at idle sounds like a lot to me - assuming this is a stock 302 we're talking about. That's about double the factory spec.

I still run a stock points ignition in mine with no problems. As long as the distributor bushings are tight - which they should be in a reman distributor, it shouldn't be a problem keeping the points gapped right. Make sure you can't move the distributor shaft back and forth too much - you'll find some specs on the board here somewhere if you search.

Single diaphram distributor? I never could get my truck to run right with the dual diaphram setup - didn't have all the stock gizmos on the engine to control the vacuum correctly any more.

 

[Bulletman]

STOCK 302with 4:10's and 31's won't have a lot of git up and go. I am just wondering if you're expecting more than the little 302 (in stock configuration) will deliver. As to the stumble, my rig duplicates yours pretty much and I have no stumbling, I peronsally would still look at the fuel system. Just my .02...........

 

[nkhd1]

changed timing to 6 no change
checked fuel connections again no change
removed line from gas pump and dropped a line n a gas can no change
checked float and was a little high changed to 1/2" to 9/16 from top of carb seemed to run rougher but has since gone back to previous.

 

[knack]

You did replace the distributor cap along with all the other stuff?

 

[nkhd1]

yep cap was changed

 

[nkhd1]

removed the line to the carb and hooked on a longer hose. Put that in a mason jar and had the wife turn the key. Seemed to fill it fairly quickly but there were a few bubbles even after the end of the hose was submerged.
<<May have found a leak in either the EGR plate or in the manifold itself. Will have to take it apart to try and locate.
keep your fingers crossed.

 

[pcf_mark]

I would check your wire routing to see if one of them is shorting to ground causing your put put noise and power loss. Lots of opinions on timing but i advanced mine all the way to 16 degrees and it woke up the throttle response w/o pinging. You could try it to see how it feels. Your balancer may have slipped or there is slop in the chain. You can always change it back.

 

[nkhd1]

pulled the intake and replaced along with the egr plate gasket.
Put a clear gas line in front of the filter on the carb. No air. So that is ruled out.
Wiring looks OK.
Found a crack on the distributor - on the shaft collar above the gear the dizzy so I swapped the distributor again. - not related but didn't want it to fall off later down the road.
Cranked it up and idled OK
Vacuum gage still fluxuating. Still getting some put put - not as bad.
Runs better but still doesnt have the throttle I think it should.
Gonna get a tape with a sticky back and put it on the crank and use the timing light on all the cylinders and see if they are all hitting consistently.
That and bypass the electrical wires one at a time.
Then I will be out of ideas again.

 

[lonesouth]

Could the balancer have shifted? Double check TDC and balancer mark.

 

[broncnaz]

You could try and time it without a light. just loosen the dizzy start the engine and rev to 3000 RPM and hold it there then adjust the dizzy until you find the smoothest running spot lock it down and take it for a spin see if there's any differance.
I'd still suspect a valve issue might be a good idea to do a compression or a leak down test.