79 CJ7 304 will not start

Tiny
AHEATH
  • 1979 JEEP CJ7
  • 100 MILES

79 cj7 304 will not start. Motorcraft 2100 was rebuilt and had it running. Next day tried to start it and heard a horrible sound like something was in the fan. Finally got it started and drove it but ran pretty rough. Next 2 days would not start even with starting fluid in the carb. New battery, cap, coil and plugs. Have gas from the filter. Starter seems to drag even with new battery and seems to discharge battery quick. This cj has sat for over 4 years without running. Did all the vac lines as per a diagram. Have what looks like a fuel nipple on the lid of the carb above the pump diaphram, and idea what that is for? Thanks

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Monday, February 4th, 2013 AT 5:23 PM

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Tiny
HMAC300
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Check for spark and fuel first then check compression your horrible sound may have been a valve acquainting it self with the piston. The nippleon top of carb may go to canniser purge for fumes. That may be the reason for the starter dragging or the battery is weak or cable.

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Monday, February 4th, 2013 AT 5:35 PM
Tiny
AHEATH
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Have spark and fuel. Tries to fire and will get small backfire out of carb. All line are hooked up to canister. Any chance that nipple is another fuel inlet to the top of the carb. I drove the jeep after it made that clattering and it hasn't done it since but will not start. Should I replace the starter and solenoid?

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Monday, February 4th, 2013 AT 5:43 PM
Tiny
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If it turns over check compression if starter turns over it should start the truck you can have battery and starter checked at auto parts normally for free

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Monday, February 4th, 2013 AT 6:00 PM
Tiny
HMAC300
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One other thing check to see if in time bring up to tdc then check to see if dist is at same on cap. You may have trhown a timing chain especially with eteh backfire you are talking about.

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Monday, February 4th, 2013 AT 6:01 PM
Tiny
CJ MEDEVAC
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HAS MR. DISTRIBUTOR BEEN OUT?....I CAN HELP YOU GET IT IN CORRECTLY

VACUUM DIAGRAMS SHOULD BE IN YOUR REPAIR MANUAL---IF IT'S NOT LIKE ORIGINAL, YOU'LL HAVE TO DECIDE WHAT PORTS TO PLUG OFF---AND WHICH ARE NEEDED TO RUN IT............OTHER THAN PWR BRAKES---ALL THAT IS NEEDED IS THE VACUUM ADVANCE AND THE PCV LINES...........UNLESS YOU ARE SMOG TESTED IN YOUR AREA.....EVEN THEN SOME PLACES SORTA HAVE SLACKER REQUIREMENTS FOR OLDER VEHICLES

IF YOU WILL, SEND PICS WITH THE BREATHER OFF AND WELL LIT WITH SOME SUNLIGHT OR LAMPS

PLEASE GIMME DIFFERENT ANGLES AND VIEWS OF THE WHOLE NINE YARDS!

I DID FIND THIS IF THIS HELPS

http://webspace.webring.com/people/dg/geer_hed/images/mc2100_vac.jpg

HOW OLD IS THIS FUEL?

IS YOUR FUEL SYSTEM SET UP WITH THIS TYPE FILTER AND PLUMBING...AS IT WAS ORIGINALLY?....SEE MY PICS (THE REGULATOR AND FUEL PRESSURE GAUGE ARE OPTIONAL)

ANY OTHER NON-STOCK MODIFICATIONS?

THE MEDIC

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Tuesday, February 5th, 2013 AT 2:03 AM
Tiny
AHEATH
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Distributor has not been off just new cap and rotor. Vehicle sat for 4 years without running. Rebuilt the carb with spray cleaner not soaked and put Seafoam and 5 gal of gas in it. Got it started with starting fluid and ran it around the block and idled pretty well. Next day started hard and idled like crap but ran. Next day would not start and sounded like something was in the fan (clacking) on cranking. Last night got it started after pumping the hell out of it but barely ran (chugging) at full throttle and engine knocking. Removed carb and am soaking to clean today. Any help is appreciated!

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Tuesday, February 5th, 2013 AT 4:21 PM
Tiny
AHEATH
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Also this is a 79 so no emissions required in AZ. Have all vac lines hooked up to the 2 CTOs with T going various places including purge canister. Is there an easier vacuum run without all the garbage? Thanks again!

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Tuesday, February 5th, 2013 AT 4:27 PM
Tiny
HMAC300
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I dont' think this is a carb problem but redo it once more and look for a float that is sunk due to alcohol in todays fuel may have ate it up. Especially if float is plastic, the inside o fit gets eaten out by alcohol an d sinks. Engine knocking doesn't sound good you may have lost a rod bearing. Check your timing chatin to dist like I said before, it could have jumped.

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Tuesday, February 5th, 2013 AT 4:34 PM
Tiny
AHEATH
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Checked cylinder 1 to distr. Seems to be good. Will remove valve covers to check for damage. Any other suggestions?

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Wednesday, February 6th, 2013 AT 3:42 PM
Tiny
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Earlier I asked ifyou had checked compression. Did you? And what is the readings accross the cylinders. These 6 cylinders were decent engines but if they sat for an extended period they would break and bend pushrods and throw rocker arms. I still thinkit's eitehr compression or timing but also is there spark i've heard no mention at all of that.

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Wednesday, February 6th, 2013 AT 4:25 PM
Tiny
AHEATH
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There is spark to the coil and distributor. Changed the plugs but now look fouled. Its a v8. Have not checked compression but will do that at noon. Cranking seems to speed up temporarily if you remove and replace coil wire. Thanks

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Wednesday, February 6th, 2013 AT 4:48 PM
Tiny
CJ MEDEVAC
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I LIKE SAVING EXPLORATORY SURGERY FOR LAST

LOOK AT YOUR TIMING COVER--IS IT CRACKED OR BULGING ANYWHERE?

IF IT IS---WE'LL STOP HERE

IF NOT, I'M SORTA LEANING ON AN IGNITION PROBLEM

I NEED TO KNOW SOME STUFF

LIKE HAS THE WIRING TO THE COIL BEEN CHANGED FROM ORIGINAL?

ANY OTHER MAJOR REWIRING?

IS THIS A PRESTOLITE OR A MOTORCRAFT SYSTEM?MOTORCRAFT USES A IGNITION MODULE LIKE THIS....SEE LINK

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_ignition-control-module-bwd_5240484-p?searchTerm=ignition+module%2Fcontrol

HAVE YOU CHANGED THE COIL?

IF SO, DID YOU GET ONE LIKE IN MY 1ST PIC?

I WANT YOU TO TELL ME THE VOLTAGE YOU HAVE AT THE POSITIVE SIDE OF THE COIL, WITH THE "KEY ON"........2ND PIC

I WANT YOU TO TEST THE PICK UP IN THE COIL----2 TESTS----I WANT YOU TO MOVE/ WIGGLE THE WIRES WHILE TESTING---- THIS MAY POSSIBLY PROVE AN INTERMITTENT SHORT IN ONE OF THE WIRES

THIS IS NOT THE END OF THE WORLD!

I'VE GOT MORE INFO----I JUST WANNA NARROW DOWN THE FACTORS

I'VE GOT MORE TESTS......THEY AIN'T HARD TO DO----I DON'T WANNA MISS NOTHING ALONG THE WAY

JUST BEAR WITH ME.......I'D RATHER BE DOING THE HANDS ON THING!

SEND --- GOOD-- LEGITIMATE--- ANSWER ALL QUESTIONS ----AND SEND INFO BACK

THE MEDIC

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Wednesday, February 6th, 2013 AT 7:49 PM
Tiny
AHEATH
  • MEMBER

The good news is i've got about 150 compression on the left and right rear cylinders. Unfortunately the other 6 don't even add up to 150. About 20, 30 and 60 front to back on both sides. Going to have the timing cover removed to see if it jumped a gear, doesn't look good for me.

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Thursday, February 7th, 2013 AT 3:43 PM
Tiny
AHEATH
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Strange that it ran decent one day and not since

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Thursday, February 7th, 2013 AT 3:52 PM
Tiny
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That's what happens when timing chains go they will run god one time then the next not even start or will run very poorly. You may have more thatn a timing chain worn ga s well but I kinda thought that was the problem especially since sitting for so long then a fire up. Timing chains stretech after a fire up like that and will jump. Also if your cam gear is plastic aluminum the plastic is brittle and when yous tart it the plastic breaks so allows chaing to stretch. Or jump time. If it it plastic and very well cold be pull thepan and clean the crap out of the oil pan as well or you will hve problems there too.

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Thursday, February 7th, 2013 AT 4:26 PM
Tiny
AHEATH
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Would that affect the compression in all but 2 cylinders though? I really appreciate your input.

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Thursday, February 7th, 2013 AT 5:10 PM
Tiny
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Yup cause the valves are opening and closing at the wrong time. But you still cold have aproblem there. After you check timing chain and if bad repair then recheck compression

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Thursday, February 7th, 2013 AT 5:27 PM
Tiny
CJ MEDEVAC
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ARE YOU SURE YOU DID AN ACCURATE COMPRESSION TEST?

ANY SORTA LEAK OR HISS, MAY MAKE YOUR READINGS BE WAY OFF...IF YOU DON'T HAVE THE GAUGE CRAMMED IN TO THE PLUG HOLE WELL

IN THE BEGINNING---YOUR "RACKET NEAR THE FAN"----ALMOST SWAYED ME!

HOW EVER YOU DROVE IT AND IT WAS ROUGH?

..........I JUST CAN'T SEE IT DRIVING WITH A JUMPED CHAIN........I MIGHT SEE YOU TWISTING THE 'STRIBUTOR AROUND AND MAYBE NURSING A REALLY CRAPPY IDLE ALONG WITH THE THROTTLE........BUT NOT ANY DRIVE TIME

GONNA LEAVE YOU WITH THIS ONE.....SEE MY 1ST ANSWER IN THIS LINK

http://www.2carpros.com/questions/1979-jeep-cj7-stalls-will-restart-after-3-4-hrs-driving-off-raod-on-hilly-terrai

I'LL CONTINUE TO WATCH----WON'T JUMP BACK IN UNLESS REQUESTED TO

THE MEDIC

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Friday, February 8th, 2013 AT 1:43 AM

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