Loping Motor or Bucking Bronco

[Tison78_CJ5]

My CJ5 '78, 304, has starter loping, a lot
Started a week ago, I noticed when in first gear, on a flat road, not pressing on the gas, it started trying to buck me out of the seat.
Today I decided to check it out.
I have inspected the distributor, little bit of white crusty oxide build up on the fire pins in the cap.
Cleaned it off. The rotor looks new.
Listening to the carb. intake, no noticeable changes in sound.
At the exhaust, both pipes sound the same, but it sounds like the key is being switched off/on.
Just checked the coil, it is good, add a .22mfd capacitor across it, no change still lopes.
I just increased the idle speed, and it cleared up. I am going to run it up the road, see if that helped.
I know it still isn't right, and it will drive me nuts, till I find the culprit.

Any Ideas where I should look.

 

[Tison78_CJ5]

Nope, didn't work.
Got half way down the mountain. Started back firing. I probably have the distributor too retarded now.
Got me thinking timing chain slack?

 

[flatie46]

304's are known for the timing chains being short lived, I replaced mine while back. They don't oil well in this area. I bought a Cloyes true dual roller for replacement. I can't really see it just going all at once though. Might be the ignition box on the fender but that's just me guessin. Does it seem to get worse as it gets warmer?

 

[Tison78_CJ5]

No, not really.
I cleaned my carb. about 3 weeks ago, and boy what a difference that made.
Maybe I should check it first. Might even put a rebuild kit in it.
It was full of trash.
I was thinking of taking my camera out tomorrow, and taking a video of my noise.
That may help people see/hear what I have wrong.
It gets so bad, it has scared me. The jerk is bad enough to bark the tires.

 

[69jeepcj]

I think I know what you are describing, it is in the carb. Readjust it! mine does it from time to time and a carb adjustment cures it.

 

[Tison78_CJ5]

I remember when I bought it the carb was in bad shape.
It sat in a field for 2 years, with a gas can under the hood to run it. The tank had rusted out.
I am real tempted to buy a rebuild kit.
Thanks, I'll flush it out again first.

 

[Tison78_CJ5]

WOW, I found the problem. As a friend says, "NEVER OVERLOOK THE OBVIOUS".
I'm ashamed to say, It is my ICM.....
Pulled a plug out, laid it on the radiator, plugged it into the coil, popped the cover off the distributor, and with the switch on, triggered the ICM.
Weak yellow flame.
Traded the coil out, and no change.
Thank God I didn't replace the timing chain.
I am going to build me a new one, and should be on the road this afternoon.
Course the motor is still going to burn some oil, but the new motor should be ready in a week.
I just can't wait a week to play.

 

[greg92jeepxj]

WOW, I found the problem. As a friend says, "NEVER OVERLOOK THE OBVIOUS".
I'm ashamed to say, It is my ICM.....
Pulled a plug out, laid it on the radiator, plugged it into the coil, popped the cover off the distributor, and with the switch on, triggered the ICM.
Weak yellow flame.
Traded the coil out, and no change.
Thank God I didn't replace the timing chain.
I am going to build me a new one, and should be on the road this afternoon.
Course the motor is still going to burn some oil, but the new motor should be ready in a week.
I just can't wait a week to play.

With the quality of electronic parts on the market today , I don't blame you for building your own ignition module. It wil last longer than any you can buy in a parts store since your going to use quality parts in your build. Being a fan of your work , hope we may see a picture of it when the jeeps up and running ?

 

[Tison78_CJ5]

Well there is your problem.
I still am going to build my own, but the old one had a cracked solder joint. So for now I have repaired it, and waiting till my potting epoxy cures.
Tomorrow will be the day of truth....
And yes, I cured my fresh epoxy in my oven, that is a good thing of being single.
It really does stink though. I'm sure my next pizza will b a real winner. ha

 

[flatie46]

Yea I remember my ex comming home one evening and saw I had some harley pistons on a cookie sheet. I was warming them up so the piston pins would slide in. She threw a fit! Hee Hee Hee

 

[Tison78_CJ5]

I ran a test with phenol formaldehyde resin "Bakelite" in our oven. I didn't know it had dripped a little.
That night the wife made us all brownies.
That is the way to get your very own lab oven.

 

[greg92jeepxj]

Always wanted to get into powder coating which involves oven curing. They recommend using an oven that will never be used for food cooking , but I don't see why you couldn't preheat parts for expansion such as flatlie46 does or cure epoxy as you are and hit the self-clean feature or maybe some oven cleaner ( which btw makes great engine degreaser) and all is well again.
I guess the powder coating gives off some chemical extract that will embed itself on to the oven walls ? So , that bad solder joint on the pc board of the module , could that just be reheated to a bright finish and good to go , providing it passes continuity and ohms check ? Just curious.

 

[Tison78_CJ5]

Absolutely, I cleaned it best I could, and laid the soldering iron to it.
Good as new.
Yea, the problem is, a lot of chemicals gas when heated. The stuff I ran in mine was very stinky, and a little explosive.
I blew the door off my first oven, after I almost poisoned the family. It is best to have electronic heat control, instead of contacts.
Phenolic resins main gas is alcohol. I had always pre-heated the oven, then turned it off. I only forgot once.
Now I have a heated vacuum chamber, and a Blue M lab oven.

 

[greg92jeepxj]

Looks like I will have to do quite a bit research and consult ( such as from yourself) before I even try. If I manage to get a set from Eastwood , I will definately post and ask for your opinion and anyone else whom would like. I blew up some stuff in my time , some were halarious and some were downright scary . Not trying to hear that again . Way things are up here , I'm afraid to fire my spud gun ! Folks probably got homeland security on speed dial .

 

[Tison78_CJ5]

When I first moved here, I had a few neighbors come over to say howdy. This is a picture of what they saw, when I opened the door.
Most said they thought it was a bomb. I was experimenting with Nano-structure plating.
Did tell a few kids it was an atom bomb.

 

[superj]

Ha ha ha, that's funny.

When you get everything up and running, set time and the carb with a vacuum gauge and it will be perfect.

 

[flatie46]

Looks like I will have to do quite a bit research and consult ( such as from yourself) before I even try. If I manage to get a set from Eastwood , I will definately post and ask for your opinion and anyone else whom would like. I blew up some stuff in my time , some were halarious and some were downright scary . Not trying to hear that again . Way things are up here , I'm afraid to fire my spud gun ! Folks probably got homeland security on speed dial .

Ive got a gass grill igniter in my tool box at work I've been saving to make a spud gun. It's amazing how far hairspray will shoot a tater!

 

[greg92jeepxj]

Ive got a gass grill igniter in my tool box at work I've been saving to make a spud gun. It's amazing how far hairspray will shoot a tater!

And loud too ! Hairspray works but gums up the "combustion chamber " , try electric shaver spray cleaner , it works well ! AHHHHHHH ! The smell of French fry potato fills the air ! Lol

 

[Tison78_CJ5]

That is the difference in location. I can shoot my gun from my front porch, no body would even look my way. All my neighbors do it too. I love the country life.....
Have a friend that built a coke bottle mortar, it took 1/2 pound of gun powder, to shoot a bottle about 1/4 mile.
He and his neighbor play mortar chicken, strange, but funny people here.