4 bent intake pushrods 4.9 300 inline 6cyl
09-15-2010, 09:11 PM
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4 bent intake pushrods 4.9 300 inline 6cyl
Hello...Just joined the site
...Ive learned many things your site..thanks..I have a '93 f150 4.9 straight 6cyl F.I.
Was selling truck and hadnt started it in around a year..ran fine when last started...but wouldnt start now without spraying gas into the throttlebody...found out it was the front fuel pump..fixed it and started right up...went out 2 days later..wouldnt start again!
called back mobile mechanics and they found a ground wire in-between the 2 tanks that had been rubbing the frame...said it could have been the cause of the 1st pump to go out...well before they came out, the guy who was going to buy it and I were trying to get it started...I sprayed a little bit of starting fluid...it would run, but like crap..nothing like it sounded when we drove it after the fuel pump fix...it just didnt sound right from the 1st turn of the key...Ive started this truck every day for over 7 years..you just know something sounded wrong...I thought the starter was acting up again..these 300's eat starters..kept trying to start it with gas after initial spray of the "death fluid"...still just a hit here and there..motor jumping around all over the place...I quit and went inside...idiot buyer must have sprayed half the can while I was inside for a minute..I came out the front door to smell ether from around the side of the house...I think he put the nail in the coffin...couldnt get it to hit a lick after that...
1st they said it was timing gears??? but we got fire to the plugs and the rotor turned...then maybe head gasket they said??? was going to pull head, upon tearing down, took off valve cover to find 4 bent pushrods out on the side of the rocker arms..They are on the right if looking from the drivers side..I guess intake side?..now there thinking timing gears again??? SO CONFUSED!!!!!
how can I easily check whats wrong?? rotor pointing to #1 cly...#1 piston at TDC... timing mark at 10*...if part of the timing gears was off, would all rockers rock?? or if cam was broke, wouldnt some just sit there?? could all the starting fluid cause such pressure that the valves stayed closed and bent the rods as the cam came around?? hope Im making some sense here?? Any help would be greatly appreciated...ps..sorry for the book thanks for sticking it out till the end.
...Ive learned many things your site..thanks..I have a '93 f150 4.9 straight 6cyl F.I. Was selling truck and hadnt started it in around a year..ran fine when last started...but wouldnt start now without spraying gas into the throttlebody...found out it was the front fuel pump..fixed it and started right up...went out 2 days later..wouldnt start again!
called back mobile mechanics and they found a ground wire in-between the 2 tanks that had been rubbing the frame...said it could have been the cause of the 1st pump to go out...well before they came out, the guy who was going to buy it and I were trying to get it started...I sprayed a little bit of starting fluid...it would run, but like crap..nothing like it sounded when we drove it after the fuel pump fix...it just didnt sound right from the 1st turn of the key...Ive started this truck every day for over 7 years..you just know something sounded wrong...I thought the starter was acting up again..these 300's eat starters..kept trying to start it with gas after initial spray of the "death fluid"...still just a hit here and there..motor jumping around all over the place...I quit and went inside...idiot buyer must have sprayed half the can while I was inside for a minute..I came out the front door to smell ether from around the side of the house...I think he put the nail in the coffin...couldnt get it to hit a lick after that...
1st they said it was timing gears??? but we got fire to the plugs and the rotor turned...then maybe head gasket they said??? was going to pull head, upon tearing down, took off valve cover to find 4 bent pushrods out on the side of the rocker arms..They are on the right if looking from the drivers side..I guess intake side?..now there thinking timing gears again??? SO CONFUSED!!!!!
how can I easily check whats wrong?? rotor pointing to #1 cly...#1 piston at TDC... timing mark at 10*...if part of the timing gears was off, would all rockers rock?? or if cam was broke, wouldnt some just sit there?? could all the starting fluid cause such pressure that the valves stayed closed and bent the rods as the cam came around?? hope Im making some sense here?? Any help would be greatly appreciated...ps..sorry for the book thanks for sticking it out till the end.
09-15-2010, 09:12 PM
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ok...went out again and found the correct timing mark...it was the "chiseled" looking mark...cleaned it all up and put a white mark with a grease pencil..easy to see now...went around numerous times...had the timing marks lined up, #1 piston @TDC and the freakin rotor was pointed towards the drivers side headlight/ac compressor area...went around many times again and in the other stroke it would be pointed at the middle of the firewall...180* of where it was landing @TDC and 10* timing...
so it seems the dist. is fine?? could it have broke a tooth? or does this sound more like the timing gears have jumped a tooth or broke a tooth?? Ive read it would be hard to jump as there is no chain...gear on gear...
I did this many times to have the rotor end up in the same 2 places every other time....any help would be greatly appreciated...thanks in advance!
so it seems the dist. is fine?? could it have broke a tooth? or does this sound more like the timing gears have jumped a tooth or broke a tooth?? Ive read it would be hard to jump as there is no chain...gear on gear...
I did this many times to have the rotor end up in the same 2 places every other time....any help would be greatly appreciated...thanks in advance!
09-15-2010, 10:45 PM
#3
Hi-Rev Motorsports
on the 93 the valves could have stuck a tad and that bent the pushrods....beings it ran before dont mess with teh distributor....replace teh bent pushrods and roll it over by hand a few times...then fire it...
09-16-2010, 09:30 PM
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well this is going to be a good one, so be prepared...
disassembled the motor today...We started by doing a complete cpmpression test all the way across the cyls...results: #1=110, #2=110, #3=5, #4=0, #5=0, #6=120 whats up with that??
so now were thinking, blown head gasket?? broken valves??? hole in piston??? broken rings?? hole in sleeve?? NONE Of THE ABOVE everything looked great, except the #1 piston had a little gouge on it..small than the eraser on a pencil...looked like some little small chunk of metal went thru and got hit by piston..you could see a tiny spot of the #1 combustion chamber on the head...no broken rings floating around...the pistons looked great except for the little gouge...the cylinder walls looked good...
went to check head...all looked pretty good...the head gasket didnt look blown anywhere to where there would be no compression...but all the pushrods were slightly bent...some worse than others..mainly the ones on #1,#3,#4,#5...so what caused all the rods to bend??
timing still seemed the culprit....so we figured for sure it was the cam gear with a sheared off tooth or teeth, being the rotor still pointed to the front drivers headlight @TDC with 10 degrees timing,instead of pointing to the #1 cyl...Ive turned this motor over so many times with the same results...had the spark plugs out..turned motor by hand...the rotor ended up pointing directly at the driver headlight/ac comprssor area...so the timing had to be way off...
so we decided to pull the timing cover off...what else could it be?? if it was the dist. the rotor wouldnt go around...so we pulled the timing cover off and looked for damage...the gears were in awesome shape...not even a chipped tooth or mark of any kindwhat the freak???how could this be?? what else could make it so far out of time...we lined up the 2 dots on the gears...(dots close to each other) as I have read on this and other forums...piston came to TDC as we had the head off and could see it clearly.....rotor still kept pointing to the driver headlight???
so we started to pull the distibutor...it didnt want to come out...like it was in a bind??...finally after some major muscle and rocking back and forth it popped out...shouldnt it just pull out easily?? We looked at the gears on it..they seemed good...shear pin intact...maybe a couple marks on the gears, but no missing teeth...rears on camshaft looked good..no missing teeth, etc...put it back in where we thought it should be(pointing to #1 cyl) went in easy...came right back out again without any effort...turned motor over with solinoid on fender...engine sounded free and smooth..no knocks or weird sounds of any kind...pistons and crank and gears all worked flawless and the rotor button lined up with #1 cyl everytime...
also, I forgot to mention while doing comp test, we had the #3 cyl plug out and turned over motor and a mix of gas and oil squirted out on every compression stroke...#4 was dry...could this have been all the ether and gas the idiot buyer squirted into it and previously mentioned?? all the gas and starting fluid was squirted into the right side of the throttle body...didnt know if that would cause the gas to go to #1,#2,#3 cylinders?? and what would all thet fluid do??? too much pressure that had to go somewhere...Please help if you can..this one is beyond about 4 of us...2 good mechanics and 2 shadetree mechanics...any ideas??? could the distributor jumped a tooth or 2??? thats the only thing we can think of...why else or HOW ELSE could it get so far out of time??? Unless someone broke into my truck and loosened the dist and took it out an put it back in a tooth or so off...that could maybe cause some of the damage???...
having head checked tomorrow for bent valves...warped or cracked head, etc...
disassembled the motor today...We started by doing a complete cpmpression test all the way across the cyls...results: #1=110, #2=110, #3=5, #4=0, #5=0, #6=120 whats up with that??
so now were thinking, blown head gasket?? broken valves??? hole in piston??? broken rings?? hole in sleeve?? NONE Of THE ABOVE everything looked great, except the #1 piston had a little gouge on it..small than the eraser on a pencil...looked like some little small chunk of metal went thru and got hit by piston..you could see a tiny spot of the #1 combustion chamber on the head...no broken rings floating around...the pistons looked great except for the little gouge...the cylinder walls looked good...
went to check head...all looked pretty good...the head gasket didnt look blown anywhere to where there would be no compression...but all the pushrods were slightly bent...some worse than others..mainly the ones on #1,#3,#4,#5...so what caused all the rods to bend??
timing still seemed the culprit....so we figured for sure it was the cam gear with a sheared off tooth or teeth, being the rotor still pointed to the front drivers headlight @TDC with 10 degrees timing,instead of pointing to the #1 cyl...Ive turned this motor over so many times with the same results...had the spark plugs out..turned motor by hand...the rotor ended up pointing directly at the driver headlight/ac comprssor area...so the timing had to be way off...
so we decided to pull the timing cover off...what else could it be?? if it was the dist. the rotor wouldnt go around...so we pulled the timing cover off and looked for damage...the gears were in awesome shape...not even a chipped tooth or mark of any kindwhat the freak???how could this be?? what else could make it so far out of time...we lined up the 2 dots on the gears...(dots close to each other) as I have read on this and other forums...piston came to TDC as we had the head off and could see it clearly.....rotor still kept pointing to the driver headlight???
so we started to pull the distibutor...it didnt want to come out...like it was in a bind??...finally after some major muscle and rocking back and forth it popped out...shouldnt it just pull out easily?? We looked at the gears on it..they seemed good...shear pin intact...maybe a couple marks on the gears, but no missing teeth...rears on camshaft looked good..no missing teeth, etc...put it back in where we thought it should be(pointing to #1 cyl) went in easy...came right back out again without any effort...turned motor over with solinoid on fender...engine sounded free and smooth..no knocks or weird sounds of any kind...pistons and crank and gears all worked flawless and the rotor button lined up with #1 cyl everytime...
also, I forgot to mention while doing comp test, we had the #3 cyl plug out and turned over motor and a mix of gas and oil squirted out on every compression stroke...#4 was dry...could this have been all the ether and gas the idiot buyer squirted into it and previously mentioned?? all the gas and starting fluid was squirted into the right side of the throttle body...didnt know if that would cause the gas to go to #1,#2,#3 cylinders?? and what would all thet fluid do??? too much pressure that had to go somewhere...Please help if you can..this one is beyond about 4 of us...2 good mechanics and 2 shadetree mechanics...any ideas??? could the distributor jumped a tooth or 2??? thats the only thing we can think of...why else or HOW ELSE could it get so far out of time??? Unless someone broke into my truck and loosened the dist and took it out an put it back in a tooth or so off...that could maybe cause some of the damage???...
having head checked tomorrow for bent valves...warped or cracked head, etc...
09-16-2010, 11:08 PM
#5
Hi-Rev Motorsports
timing cant jump unless the distributor gear pin is broken or the cam gear is busted...since you are sure of neither it hasnt jumped....unless the shear pin is really broken and you just dont see it...
pushrods bent for 1 of 2 reasons....
valves stuck and they bent trying to force the valve open....OR so much starting fluid int he chambers and it backfired hard enough to cause reversion in the valve train which will instantly bend valves and pushrods...
pushrods bent for 1 of 2 reasons....
valves stuck and they bent trying to force the valve open....OR so much starting fluid int he chambers and it backfired hard enough to cause reversion in the valve train which will instantly bend valves and pushrods...
09-17-2010, 07:09 PM
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dist gear was fine....shear pin fine...timing gears look great...machine shop said the head gasket was blown between #3, #4 & #5...#3 valve guide cracked...all valves checked out good...no cracks in head...
the thing had to jump time at the dist gear...there is no other explaination?? Unless a gremlin pulled out the dist. in the middle of the night and put it back in a tooth or 2 out??? Ive had other people say its possible, but very, very rare....and the dist was a bear to get out...like it was stuck or in a bind..the guy trying to pull on it weighed over 300 lbs...big guy...I'm 6'4" 230 lbs and I couldnt get it to budge...
putting it back together tomorrow with a set of new pushrods...thanks for all your help, unless you can think of any other cause?
the thing had to jump time at the dist gear...there is no other explaination?? Unless a gremlin pulled out the dist. in the middle of the night and put it back in a tooth or 2 out??? Ive had other people say its possible, but very, very rare....and the dist was a bear to get out...like it was stuck or in a bind..the guy trying to pull on it weighed over 300 lbs...big guy...I'm 6'4" 230 lbs and I couldnt get it to budge...
putting it back together tomorrow with a set of new pushrods...thanks for all your help, unless you can think of any other cause?
09-17-2010, 11:28 PM
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there was liquid in the #3 piston...a bunch gushed out right before check the compression..we had a few plugs out trying to look into the plug holes...
The timing mark I used was the correct one...tiny little line..not the square notch(which looks like a file on edge did it)...the v-notch Im referring to in on the sawtooth/degree thing(not sure what its called) it has many little v's and one big one at 10 degrees...you can easily read all the increments...we took off the timing cover and the gears were fine and both timing dots lined right up when @TDC....its the dist/rotor that was pointing in the wrong direction...
if the damper/balancer has slipped the #1 piston wouldnt hit TDC when the marks lined up..correct? believe me..there have been close to six guys working on this thing in the last week...4 of them are pretty knowledgable and 3 are mechanics by profession...no one can figure it out???
like I said before..one valve guide cracked on the #3 cyl...gas in the oil...antifreeze in the oil...machine shop says head is good..valves were seated nicely...no bent valves..just all pushrods bent.."ALL" of them..#1,#3,#4,#5 intake side pushrods push out and stting against the side of their rockers...had a blown head gasket due to the fluid(gas & or water) or starting fluid or both or major combustion due to all the gas & starting fluid sitting in the cylinders...timing gears are fine..cam gear is the metal gear, so it couldnt have spun or slipped...the only weak link is the distributor...all rocker arms go up and down as they should(no broke cam)...rotor turns around fine, always ending up in the same place if the timing is set at 10*TDC or if the timing gear dots are lined up @TDC..I have never seen anything like this before..its beyond all of us...
The timing mark I used was the correct one...tiny little line..not the square notch(which looks like a file on edge did it)...the v-notch Im referring to in on the sawtooth/degree thing(not sure what its called) it has many little v's and one big one at 10 degrees...you can easily read all the increments...we took off the timing cover and the gears were fine and both timing dots lined right up when @TDC....its the dist/rotor that was pointing in the wrong direction...
if the damper/balancer has slipped the #1 piston wouldnt hit TDC when the marks lined up..correct? believe me..there have been close to six guys working on this thing in the last week...4 of them are pretty knowledgable and 3 are mechanics by profession...no one can figure it out???
like I said before..one valve guide cracked on the #3 cyl...gas in the oil...antifreeze in the oil...machine shop says head is good..valves were seated nicely...no bent valves..just all pushrods bent.."ALL" of them..#1,#3,#4,#5 intake side pushrods push out and stting against the side of their rockers...had a blown head gasket due to the fluid(gas & or water) or starting fluid or both or major combustion due to all the gas & starting fluid sitting in the cylinders...timing gears are fine..cam gear is the metal gear, so it couldnt have spun or slipped...the only weak link is the distributor...all rocker arms go up and down as they should(no broke cam)...rotor turns around fine, always ending up in the same place if the timing is set at 10*TDC or if the timing gear dots are lined up @TDC..I have never seen anything like this before..its beyond all of us...
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09-18-2010, 03:09 PM
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hydrolocked?
If your head gasket was leaking, that's where the oil and/or coolant would have entered the cylinders, filling them at least to the point where it could have bent your valve pushrods. Fluid doesn't compress. I have seen severely hydrolocked engines bend piston rods and twist cranks. It's a possible explanation.
If that is the case, then you got lucky. Valve pushrods are cheap!
If that is the case, then you got lucky. Valve pushrods are cheap!
09-19-2010, 08:37 AM
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I'd put her back together with new pushrods and head gasket and just live with the mystery.
