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cruiser
08-12-2013, 06:43 PM
1981 351 with pertronics ignition. Last 3 times out ran great. Went to start it and had a definate miss. Checked the carb. Drivers side 3 1/2 turns out, other side 2 1/2. Have not touched the engine since i bought it this spring. Plugs are old but clean and light brown.. Inside the dist. cap the towers are grooved from the cap not being on right at some point. should the choke plate be 100% open when the engine is warmed up? I noticed the small cotter pin is missing from the linkage than rides on the electric choke. Any suggestions, new plugs and distributor cap tomorrow for sure.

thatsmrmastercraft
08-12-2013, 07:03 PM
Choke should be lightly closed on a cold engine and 100% open after 90 seconds with the key on. The imbalance of the mixture screws could masking a clogged idle passage on one side. With the engine off, remove the mixture screw and put a rag over the top of the carb. Insert the tube from a can of carb cleaner into the mixture screw hole and spray it out. Do this for both sides. Start with the mixture screws at 1 1/2 turns out and see what you get.

The notched dist cap and worn plugs could all add up to your problem. Keep us posted on your results.

cruiser
08-12-2013, 07:23 PM
will do as you suggest. Just found two cracked terminal towers, cracks are on the outside, but im sure they travel to the inside. can't see cracks on the inside but bet their jumping.'

thatsmrmastercraft
08-12-2013, 07:24 PM
will do as you suggest. Just found two cracked terminal towers, cracks are on the outside, but im sure they travel to the inside. can't see cracks on the inside but bet their jumping.'

Sounds like you may have found the cause. Might consider changing the cap before doing any carb work, though the carb sounds like it needs some attention.

T-Rager
08-12-2013, 07:31 PM
Be sure to check the plug wires as well.

cruiser
08-12-2013, 08:46 PM
ok to all replys, the choke butterfly will not open, only about 1/3 .seems to hit a dead stop. Am i missing something?

thatsmrmastercraft
08-12-2013, 09:14 PM
First take note of where the choke is set, then loosen the three screws on the choke cap and try rotating the cap to get more choke blade travel.

cruiser
08-13-2013, 04:03 PM
Just installed new cap, miss is gone. Trying to adjust carb. Choke plate will not open the choke cam is stopping the plate from opening. Hitting the stop post. ?????

thatsmrmastercraft
08-13-2013, 04:27 PM
I would Google Holley marine 4160 exploded view and compare your linkage. You could post some pics here and we could take a look too.

cruiser
08-13-2013, 05:19 PM
just adjusted the carb with a vacuum guage, pretty easy. Running great now. not to sure about the choke. Will take pics and try to post. Thanks for the help.

cruiser
08-13-2013, 05:44 PM
cant get pics to post. If the electric choke does not work, would that keep the linkage from opening the choke plate? Even if i try to open the choke plate it hits a post that sticks out from behind the electric choke. Im not sure if the linkage is set up correctly. I will continue to try to upload pics.

cruiser
08-13-2013, 05:54 PM
couple of pics, sorry for the poor quality. first pic the post that the plastic cam is hitting, (hard stop.)99360
second pic bottom of linkage from the choke plate. hitting the plastic, cant go down any further.??
99361

thatsmrmastercraft
08-13-2013, 06:14 PM
Hard to tell from those pics, but if working properly, you can always manually open the choke. I will be able to take a better look shortly.

cruiser
08-13-2013, 06:34 PM
thats my problem. no matter what i do i cant open the choke plate. I hit a hard stop. That is what makes me believe the electric choke or linkage is incorrect.

thatsmrmastercraft
08-13-2013, 10:28 PM
I would take the choke cap off and see if that is the problem. There is a coil spring under very little pressure inside and there is a notch in the choke housing connected to the linkage that accepts the end of the coil spring.

cruiser
08-14-2013, 08:50 AM
Will look at that choke spring this morning. has to be something wrong to stop the choke plate so hard.

cruiser
08-14-2013, 11:10 AM
turned on the ignition, 12 volts to the choke housing. Choke plate did not open. removed the choke housing and the bi-metal spring was warm to the touch. Gave full throttle and the choke plate did not open. Something is not right with the setup. Will go down and try to take better pics the linkage setup.

thatsmrmastercraft
08-14-2013, 11:15 AM
Did you turn the choke cap to try to open the choke?

Spring should be warm as the 12 volts warms the bi-metalic spring which causes expansion at different rates.

cruiser
08-14-2013, 11:56 AM
99378

99379couple more pics. Yes i turned the choke cap and still hit a dead stop. With the choke assy. off i get a lot more travel in the assy. When i hook it all up it will not work correctly.

cruiser
08-14-2013, 12:26 PM
Just figured it out. I noticed a small cotter pin hole at the bottom of the choke linkage. it is missing. the L at the bottom had jumped from under the counterweight to the top of the plastic. moved it below and everything works as it should. Will make a temporary until i can get the proper cotter pin. Thanks for all your help. It goes to show ya. stick with it, everything is fixable.:):dance::dance::):)

thatsmrmastercraft
08-14-2013, 12:37 PM
With everything disconnected, can you open the choke fully?

cruiser
08-14-2013, 12:49 PM
yes. all working great.

thatsmrmastercraft
08-14-2013, 12:56 PM
There is a plastic piece that sits into the carb housing that the linkage that connects the choke housing to the choke plate slides through. Is this causing the binding?

cruiser
08-14-2013, 01:31 PM
that was it. the cotter pin came out and allowed it to jump to the top instead of underneath. That is where it was hanging up. turned on the key and watched the choke plate open. All is good. Thanks for your continued help.

thatsmrmastercraft
08-14-2013, 01:32 PM
that was it. the cotter pin came out and allowed it to jump to the top instead of underneath. That is where it was hanging up. turned on the key and watched the choke plate open. All is good. Thanks for your continued help.

No problem. Glad we got it worked out. :toast:

cruiser
08-16-2013, 03:42 PM
just put in a new rotor. miss is back. do you have to retime the engine ?? pertronix magnets out.

cruiser
08-16-2013, 07:26 PM
no spark to number 3 cyl. changed wire nothing , no spark coming from #3 tower on distributor. Wire to ground- nothing. Changed rotor 180 spark went to another cylinder. Is this the way pertronix fails. Cap is new, rotor is new

thatsmrmastercraft
08-16-2013, 09:39 PM
no spark to number 3 cyl. changed wire nothing , no spark coming from #3 tower on distributor. Wire to ground- nothing. Changed rotor 180 spark went to another cylinder. Is this the way pertronix fails. Cap is new, rotor is new

Got me stumped.

cruiser
08-17-2013, 09:51 AM
going to get on pertronix website. I think it has to do with the magnets.

cruiser
08-17-2013, 07:08 PM
Had 3 guys on the motor today. All good with engines. All agree after checking everything out. It is either the magnets or the pertronix module. Called Summit and they never heard of such a thing .Will call pertronix on Monday Morning. Will report with findings.

cruiser
08-18-2013, 10:30 PM
does it make more sense to fix a distributor thats 32 years old or purchase a new distributor and high performance coil??

cruiser
08-19-2013, 08:12 PM
talked to 3 techs at pertronix. Finally figured out the magnets were all pulling NORTH. They have to pull SOUTH. IF they are not installed in the right direction the module does not sense to fire. IF you ever have to do this you will need patience. runs smooth and starts right up.