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Discussion Starter · #1 ·
A few days ago I decided to attempt to tackle a valve adjustment (I now regret). Seems that I followed some wrong advice, and the first time I adjusted them It was running rough, very shaky, slow acceleration. I thought that I was to tighten the retaining bolt until I could no longer spin the pushrod, and then 1 1/4 turn further. Most likely too tight I realize now. I had to work that night so I ran it longer than I would have liked given it's condition. That night I got back to work after some reading and set them looser, to the point of no valve lash following the TDC cylinder 1 -> set both valves -> repeat in firing order. After that it would start for a few seconds but wouldn't stay running. Was less shaky. At this point I was/am thinking I fkd something major up.

Have tried readjusting following EO/IC, and 1 valve at a time (exhaust opens set intake, intake opens fully and closes 2/3 set exhaust) to no avail. I ran a compression test, 100PSI on all cylinders but forgot to depress throttle/open intake plate. That worried me as well. At this point I am wondering if I need to set preload? It will crank but won't fire now, and I've been looking all over to find some guidance. Believe it has non-adjustable rockers but I can't seem to find any definitive answers. Next steps at the moment, I have a dial indicator on the way to see if I killed the cam. Any help is greatly appreciated. I'm stuck, and have been considering that I need new heads and a cam. Either that or a good used engine. A side note, I had replaced the starter and noticed about half the teeth on my flywheel have chips... Really don't want to just sell this car..

About to run the compression test with throttle depressed, and then by dropping oil in the spark plug hole.
Thanks in advance
 

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Discussion Starter · #2 ·
One more thing, on a couple cylinders if I push up on the valvespring side of the rocker, I can push feel and see the pushrod going down. I doubt that is normal and was suspecting failing lifters. I have hydraulic lifters in the stock heads correct?
 

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A few days ago I decided to attempt to tackle a valve adjustment (I now regret). Seems that I followed some wrong advice, and the first time I adjusted them It was running rough, very shaky, slow acceleration. I thought that I was to tighten the retaining bolt until I could no longer spin the pushrod, and then 1 1/4 turn further. Most likely too tight I realize now. I had to work that night so I ran it longer than I would have liked given it's condition. That night I got back to work after some reading and set them looser, to the point of no valve lash following the TDC cylinder 1 -> set both valves -> repeat in firing order. After that it would start for a few seconds but wouldn't stay running. Was less shaky. At this point I was/am thinking I fkd something major up.

Have tried readjusting following EO/IC, and 1 valve at a time (exhaust opens set intake, intake opens fully and closes 2/3 set exhaust) to no avail. I ran a compression test, 100PSI on all cylinders but forgot to depress throttle/open intake plate. That worried me as well. At this point I am wondering if I need to set preload? It will crank but won't fire now, and I've been looking all over to find some guidance. Believe it has non-adjustable rockers but I can't seem to find any definitive answers. Next steps at the moment, I have a dial indicator on the way to see if I killed the cam. Any help is greatly appreciated. I'm stuck, and have been considering that I need new heads and a cam. Either that or a good used engine. A side note, I had replaced the starter and noticed about half the teeth on my flywheel have chips... Really don't want to just sell this car..

About to run the compression test with throttle depressed, and then by dropping oil in the spark plug hole.
Thanks in advance
Hello LTDProject,

First let me say you really need the 1968 Ford Factory Service Manual if you are going to work on the car. They are out there, check E-Bay. Secondly, it sounds like you may have in the least burnt some of the valves or even destroyed a cam lobe or two. It's hard to say without a more detailed investigation.

The 1968 Windsor engines have adjustable rocker arms, that's why you were able to adjust the lifter preload in the first place ;) .

I think you are on the right track in checking the cam lobes for damage first, if any show lower lift than specified in the service manual, then you probably made a considerable amount of metal shavings inside the engine and I would strongly encourage you to completely tear down the engine and clean it out otherwise you risk damage to any new and expensive parts you install.

The service manual (I have the 68 Ford full size manual) does say 1 turn down past zero lash, but it's how you feel zero lash that's the important part. If your lifters bleed down quickly, spinning the pushrod method might fool you into thinking you have zero lash when you might be beyond it.

I use the paper method for determining zero lash. Just stick a piece of printer/copy paper between the valve stem tip and the rocker with the rocker nut loose you should be able to pull on the paper without drag, the moment you have zero lash, even with a bled down lifter you'll feel a very noticeable drag on the paper pulling on it. Then spin the rocker nut one more turn.

Now obviously you want to be on the base circle of the camshaft when doing this and nowhere near or on the lobe itself. Easy way to determine this is rotate the crankshaft until the valve appears to have stopped moving upwards and is seated, then rotate the crankshaft another 3/4-1 turn. That ensures you are on on the base circle. Rinse and repeat for the remaining valves.

On the flex plate how bad are the teeth? Some wear is normal and if the starter isn't making unusual noises whilst cranking I wouldn't worry about it, otherwise you'll have to remove the transmission to replace the flex plate. If you do, do not use ATP flex plates, they aren't made well at all anymore it seems. The Pioneer brand seems to be ok for now. I just bought an ATP flex plate for our 1968 Ford XL and it was horrible and not usable. Brand new part ended up in the rubbish bin.

Just keep in mind used old 302's aren't getting any younger. Used carbureted ones are going to be high mileage, leaky or otherwise problematic now. You could always buy a crate 302 engine from say Summit, etc or you could just work with what you have. Your 68 is an antique and parts are getting expensive and hard to find. I feel this pain also as I have two '68's, three 66's and had a '68 LTD parts car I recently disposed of.

Good Luck,

Cheers
 

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1 1/4 turn? where did that come from? 3/4 is the max the book says and most only do 1/2 turn.
Personally, start over with the valves. Bring #1 to firing point and loosen ALL the rockers till the pushrod rotates. Rotate crank 1/4 turn and check ALL again adjust till no pushrod rotation. 1/4 turn of the crank and do this until you've made 2 complete rotations of the crank bringing the rotor pointing at #1 again. Then tighten all the rockers another 1/2 turn.
Then start it and let it adle and do this starting at #1 cyl. Loosen till it quacks then tighten until it doesn't SLOWLY and then another 1/2 turn. Go to the next one.
 

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Discussion Starter · #5 ·
Hello LTDProject,

First let me say you really need the 1968 Ford Factory Service Manual if you are going to work on the car. They are out there, check E-Bay. Secondly, it sounds like you may have in the least burnt some of the valves or even destroyed a cam lobe or two. It's hard to say without a more detailed investigation.

The 1968 Windsor engines have adjustable rocker arms, that's why you were able to adjust the lifter preload in the first place ;) .

I think you are on the right track in checking the cam lobes for damage first, if any show lower lift than specified in the service manual, then you probably made a considerable amount of metal shavings inside the engine and I would strongly encourage you to completely tear down the engine and clean it out otherwise you risk damage to any new and expensive parts you install.

The service manual (I have the 68 Ford full size manual) does say 1 turn down past zero lash, but it's how you feel zero lash that's the important part. If your lifters bleed down quickly, spinning the pushrod method might fool you into thinking you have zero lash when you might be beyond it.

I use the paper method for determining zero lash. Just stick a piece of printer/copy paper between the valve stem tip and the rocker with the rocker nut loose you should be able to pull on the paper without drag, the moment you have zero lash, even with a bled down lifter you'll feel a very noticeable drag on the paper pulling on it. Then spin the rocker nut one more turn.

Now obviously you want to be on the base circle of the camshaft when doing this and nowhere near or on the lobe itself. Easy way to determine this is rotate the crankshaft until the valve appears to have stopped moving upwards and is seated, then rotate the crankshaft another 3/4-1 turn. That ensures you are on on the base circle. Rinse and repeat for the remaining valves.

On the flex plate how bad are the teeth? Some wear is normal and if the starter isn't making unusual noises whilst cranking I wouldn't worry about it, otherwise you'll have to remove the transmission to replace the flex plate. If you do, do not use ATP flex plates, they aren't made well at all anymore it seems. The Pioneer brand seems to be ok for now. I just bought an ATP flex plate for our 1968 Ford XL and it was horrible and not usable. Brand new part ended up in the rubbish bin.

Just keep in mind used old 302's aren't getting any younger. Used carbureted ones are going to be high mileage, leaky or otherwise problematic now. You could always buy a crate 302 engine from say Summit, etc or you could just work with what you have. Your 68 is an antique and parts are getting expensive and hard to find. I feel this pain also as I have two '68's, three 66's and had a '68 LTD parts car I recently disposed of.

Good Luck,

Cheers
Thanks for the quick reply, is there a way to determine if I burnt valves before going ahead and pulling the heads? And I've realized that as well, manual in the mail. Seems that I initially overtightened considerably. Anxious to measure valve lift when the dial comes in. But I was going to say I've turned the engine over so many times trying to get this right that I know none of the lobes are completely worn down.

Good info on the flex plate... Think I'll leave it til I hear something.

169688


and ricky like I said, bad advice, on the internet. However my question now is, should I bother trying to adjust the valves still and risk further damage. Or just move on to diagnosis and replacement?

Thanks for the proper info on adjustment.
 

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Thanks for the quick reply, is there a way to determine if I burnt valves before going ahead and pulling the heads? And I've realized that as well, manual in the mail. Seems that I initially overtightened considerably. Anxious to measure valve lift when the dial comes in. But I was going to say I've turned the engine over so many times trying to get this right that I know none of the lobes are completely worn down.

Good info on the flex plate... Think I'll leave it til I hear something.

View attachment 169688

and ricky like I said, bad advice, on the internet. However my question now is, should I bother trying to adjust the valves still and risk further damage. Or just move on to diagnosis and replacement?

Thanks for the proper info on adjustment.
Hello LTDProject,

Yes there is a way to see if there is valve seat damage, you'll need a cylinder leak down tester. You can get a cheap kit from Harbor Freight. Basically you put the cylinder you want to test at TDC on the compression stroke, then remove the spark plug and screw in the air hose attachment. You can make something your self if you are handy with an old spark plug and some fittings (remove the porcelain and mate an air hose fitting to it). You will pressurize the cylinder with 80-100 PSI of shop air and then listen for air hissing out the exhaust pipe or carburetor. If you do, you know that valve is not sealing and alter your plan of attack from that point.

I'm glad you ordered the 1968 Ford factory shop manual for the car. In it you will see to adjust the valves on a stock 302 it's one full turn down past zero lash. Right from the source, can't argue with that. :)

The flex plate teeth do not look too bad. If it bothers you replace it, but it still has life left in it.

Say do you have any pictures of your car? I would like to see it if that's ok. I have a weird thing for 66 and 68 full size Fords :p

Cheers
 

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Seen worst teeth then that still do the job. If you have a comp gauge that will tell you. Poor man's comp gauge, your finger in the spark plug hole. The piston won't touch it. But your'll either get comp or you won't. That's how they did it back in 68. Just as adjusting the points with a match book cover and "seat of the pants" was if she's running good.
 

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Discussion Starter · #8 · (Edited)
Been really busy with work, but had the time this morning to run the leak down test. here are the results: cylinder 1: 15% cylinder 2: 20% cylinder 3: 9% cylinder 4: 7% cylinder 5: 6% cylinder 6: 3% cylinder 7: 9% cylinder 8: 8%

Is 20% leak within the acceptable range? cylinder 2 was the only one concerning me, ran the test 3 times.

Dial indicator came in so I'm about to test for lift. Will report back. Also noticed that most my rockers would 'rock' back and forth a considerable amount. Saw a video stating that if they shake too much then they are not at zero lash yet. Going to try the paper method. Any chance that is why she won't start? Going to set preload to 19 ft lb.(so long as that puts me between 1/2 to 1 full turn) after checking lift..

and here it is :)
169710
 

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Discussion Starter · #9 ·
Again busy with work, but got around to testing for lift today and only had a few valves with consistent results. Believe I have some collapsed lifters at the least. Not even going to bother with trying to set it again. Really curious to break her open and see what all I damaged.

On to the build sheet. New parts
 

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to set valves firing order is 1542 6378 now wright this down 1542 then directly underneath the remaing firing order 6378. now 1 above 6 ,5 above 3,, 4 above 7,,, 2 above 8 ,,, when opposite cyl rockers rock one coming up other going down the cyl above or below is ready to set so when cyl one rockers rock then cyl 6 ready when cyl 6 rocks then cyl one ready n so on!!!!! back off nut till u have play then slowly rotate pushrod untill slight drag no play then .one half turn ,, always built mine one half turn ! its never failed me this way!!!!!! this will work on chevs also !!
 

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Discussion Starter · #11 ·
to set valves firing order is 1542 6378 now wright this down 1542 then directly underneath the remaing firing order 6378. now 1 above 6 ,5 above 3,, 4 above 7,,, 2 above 8 ,,, when opposite cyl rockers rock one coming up other going down the cyl above or below is ready to set so when cyl one rockers rock then cyl 6 ready when cyl 6 rocks then cyl one ready n so on!!!!! back off nut till u have play then slowly rotate pushrod untill slight drag no play then .one half turn ,, always built mine one half turn ! its never failed me this way!!!!!! this will work on chevs also !!
Thanks, so do you think that I should try to adjust them and start it? Because at this point I am able to push down the pushrods by hand even when already tightened down. I have been planning on just rebuilding once I save some money up..
 

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Thanks, so do you think that I should try to adjust them and start it? Because at this point I am able to push down the pushrods by hand even when already tightened down. I have been planning on just rebuilding once I save some money up..
So if u can push down on pushrod approx 1/8 inch, n springs back up, means ur lifter has bled down aka no oil press/or new lifters??? so again as i replied earlier, move pushrod up n down till no play rotataing gently with fingers till u feel pushrod tighten very slightl on spring pressure,, n play gone!!! that is zero lash, now turn down 1/2 turn,,, u should still be able to push down on lifter spring!! n it return up!!! if u have a lifter that does not push down on spring,, it meens it is loaded with oil press, so again loosen off till play slowly rotate push rod till play gone n slight resistanc turn down 1/2 turn,,, but then if loaded it wont push further on spring,,, because that lifter is loaded oil press ,,, keep rotating on opposite cyl firing n adjust all,,,, when u start some lifters will rattle till oil press comes up! Thenu should see all rockers getting oil up from push rods with oil presuure ! then quiet down!! remember opposite valves rocking on cyls
6 rocks cyl 1 is ready 1 rocks cyl 6 s ready etc,,, 5 rocks 3 is ready,, 3 rocks 5 is ready !!!!! and so on
1542
6378
 

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Discussion Starter · #13 ·
So if u can push down on pushrod approx 1/8 inch, n springs back up, means ur lifter has bled down aka no oil press/or new lifters??? so again as i replied earlier, move pushrod up n down till no play rotataing gently with fingers till u feel pushrod tighten very slightl on spring pressure,, n play gone!!! that is zero lash, now turn down 1/2 turn,,, u should still be able to push down on lifter spring!! n it return up!!! if u have a lifter that does not push down on spring,, it meens it is loaded with oil press, so again loosen off till play slowly rotate push rod till play gone n slight resistanc turn down 1/2 turn,,, but then if loaded it wont push further on spring,,, because that lifter is loaded oil press ,,, keep rotating on opposite cyl firing n adjust all,,,, when u start some lifters will rattle till oil press comes up! Thenu should see all rockers getting oil up from push rods with oil presuure ! then quiet down!! remember opposite valves rocking on cyls
6 rocks cyl 1 is ready 1 rocks cyl 6 s ready etc,,, 5 rocks 3 is ready,, 3 rocks 5 is ready !!!!! and so on
1542
6378
Alright thanks for the info, currently working a lot of doubles so this weekend I'll try again. And if I'm not satisfied, the heads are coming off
 

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Discussion Starter · #14 ·
My fault, thought I had posted back on here. Got around to taking the heads off. I have at least 3 lifters that I can't push down on at all, the rest go down and spring right back up. The pushrods were all straight, lifters didn't look worn, and all around valves are fine. Can I remove the cam without dropping the engine? I already have the radiator off.

Also any recommendations on a cam and lifter kit, I want something mild not too aggressive. Wanted an E303 but I am not sure if it's compatible. Hydraulic rollers would be nice..
 

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My fault, thought I had posted back on here. Got around to taking the heads off. I have at least 3 lifters that I can't push down on at all, the rest go down and spring right back up. The pushrods were all straight, lifters didn't look worn, and all around valves are fine. Can I remove the cam without dropping the engine? I already have the radiator off.

Also any recommendations on a cam and lifter kit, I want something mild not too aggressive. Wanted an E303 but I am not sure if it's compatible. Hydraulic rollers would be nice..
heads dont need to be removed to check lifters if u have cam damage then u wll have lifter damge, E303 is roller cam, best used with higher stall n higher ratio gears, plus is a roller, u will need a retrofit kit etc will be very expensive,, plus u will need to know what u r doing,,, no offence but u r in way over ur head to be doing this from your replies/questions etc,,, best is new hyd lifters n a mild cam around 218 duration mid 450 lift on a 110 centerline and prof help comp cams sells kits,,, dont forget u will need a zinc oil with flat tappet cam,,, and if the heads have never been done with new unleaded hardened seats u will need a lead substitute additive in your fuel at all times !!!! Hope this helps !!
 

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Discussion Starter · #16 ·
Thanks for the reply, looking at getting a comp 268H. And I'm already planning on new heads, carb and a handful of other things. I can admit to being in over my head, but I've got time, and a daily so I'm willing to take my time and learn. It was already running rough, so I figure an engine rebuild or swap is necessary sooner rather than later.. In my mind it doesn't make sense to pay someone to rebuild it, so I'll figure it out. Thanks again.

But does anyone know for a fact if I can pull the cam without dropping the engine? Seems the only things in the way are the bumper and flipping headlight assembly.
 

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Thanks for the reply, looking at getting a comp 268H. And I'm already planning on new heads, carb and a handful of other things. I can admit to being in over my head, but I've got time, and a daily so I'm willing to take my time and learn. It was already running rough, so I figure an engine rebuild or swap is necessary sooner rather than later.. In my mind it doesn't make sense to pay someone to rebuild it, so I'll figure it out. Thanks again.

But does anyone know for a fact if I can pull the cam without dropping the engine? Seems the only things in the way are the bumper and flipping headlight assembly.
Yes if u remove rad n possibly hold down latch assembly for hood, maybe grille ,, cam should come out lots o break in lube on cam n lifters base,,, be all ready n when u fire up ,, and zinc oil!!!!!! gm sells engine break in lube,, or lucas or comp sells it to very important !!!! keep engine around 1500-2000 rpm till warmed up varying rpm about 20 mins,,, drop oil n filter n freshen up !!
 
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