460 ticking/missing
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Joined: Feb 2002
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From: Cleveland, WI USA
460 ticking/missing
Greetings oh Gods of the big block!
I have a 74ish 460 in my 78 F150. It's got a bad ticking that seems to come and go. On start up, it seems to be missing but goes away when the ticking does.
I thought it might be an exhaust leak at the manifold-to-h pipe, but that wouldn't go away. It's happen all the time.
Two others suggested I might have a collapsed lifter that's causing the missing and ticking. Seems logical to me, what do you think?
If I decide to replace the lifters, what else should I do. This is just my off-road toy so I'm not looking to go through the expense of a complete rebuild. Only what's absolutely necessary.
Thanks in advance!
Kevin K.
I have a 74ish 460 in my 78 F150. It's got a bad ticking that seems to come and go. On start up, it seems to be missing but goes away when the ticking does.
I thought it might be an exhaust leak at the manifold-to-h pipe, but that wouldn't go away. It's happen all the time.
Two others suggested I might have a collapsed lifter that's causing the missing and ticking. Seems logical to me, what do you think?
If I decide to replace the lifters, what else should I do. This is just my off-road toy so I'm not looking to go through the expense of a complete rebuild. Only what's absolutely necessary.
Thanks in advance!
Kevin K.
Post Fiend
Joined: Nov 2001
Posts: 6,748
Likes: 118
From: Tallassee, ALabama
460 ticking/missing
Get some ear plugs?!?!?!?
and continue to drive it....
You could replace the lifters and use the old cam, happens all the time....you just don't want to use old lifters on a new cam.....you will need an intake gasket set, valve cover gaskets and of course a set of lifters. I would replace them all if I replaced any.
and continue to drive it....You could replace the lifters and use the old cam, happens all the time....you just don't want to use old lifters on a new cam.....you will need an intake gasket set, valve cover gaskets and of course a set of lifters. I would replace them all if I replaced any.
Junior User
Joined: Apr 2002
Posts: 63
Likes: 2
From: Port Orchard
460 ticking/missing
I'd bet it's either a collapsed lifter or a dished lifter w/ a cam lobe that's trying to make itself round.
Assuming we're betting correctly here, if this is on an exhaust, then it's only a matter of time before you burn a valve. If it's an intake, not as bad but still a pain.
Start with a complete, accurate compression check and try to make an educated decision based on the readings you get.
If the overall readings are way low, or wildly apart then you either do a complete rebuild or roll the dice with a cam/lifter/valve job (and bet the rings and cylinder walls are decent). This can be done w/ the engine in the vehicle.
If there's <20% difference between the best and worst cylinder it's probably an offending lifter and possibly the cam as mentioned above. I'd pull the intake and the pushrods etc. on the worst cylinder (or the one you know is ticking) and have a look at the lifters and lobes.
Keep in mind, if you see dishing, pitting or scoring on two or four lifters, you wasting your time and money dropping in new lifters.
There's good chance they'll be just as hashed up in a few thousand miles. Better to replace the cam and lifters as a set.
Also suggest you inspect the rockers, fulcrums and pushrods and make sure they're acceptable. Bite the bullet and replace them if they're marginal. Going cheap here is not going to give you a quality result that will go the distance.
This is also the perfect oportunity to get a cam that has a profile more to your liking. Be sure to do your home-work and research before chosing a cam. This board has TONS of info on good and bad cams for these engines.
Good luck!
John
Assuming we're betting correctly here, if this is on an exhaust, then it's only a matter of time before you burn a valve. If it's an intake, not as bad but still a pain.
Start with a complete, accurate compression check and try to make an educated decision based on the readings you get.
If the overall readings are way low, or wildly apart then you either do a complete rebuild or roll the dice with a cam/lifter/valve job (and bet the rings and cylinder walls are decent). This can be done w/ the engine in the vehicle.
If there's <20% difference between the best and worst cylinder it's probably an offending lifter and possibly the cam as mentioned above. I'd pull the intake and the pushrods etc. on the worst cylinder (or the one you know is ticking) and have a look at the lifters and lobes.
Keep in mind, if you see dishing, pitting or scoring on two or four lifters, you wasting your time and money dropping in new lifters.
There's good chance they'll be just as hashed up in a few thousand miles. Better to replace the cam and lifters as a set.
Also suggest you inspect the rockers, fulcrums and pushrods and make sure they're acceptable. Bite the bullet and replace them if they're marginal. Going cheap here is not going to give you a quality result that will go the distance.
This is also the perfect oportunity to get a cam that has a profile more to your liking. Be sure to do your home-work and research before chosing a cam. This board has TONS of info on good and bad cams for these engines.
Good luck!
John
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Joined: Feb 2002
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From: Cleveland, WI USA
460 ticking/missing
Thanks for the advice all!
I decided to pull the manifold and replace the lifters on Saturday. It was actually a very easy process. I inspected all the lifters and the cam lobes and all looked well. No dishing or scoring. It seems to run much better now.
I also picked up a real nice compression tester from my brother this weekend so I'll be checking the cylinders tonight.
Now I just have to replace the rear main seal. After taking the truck to the gas station and back, I parked it in the garage. In about 5 minutes I had a 8" dia. oil puddle. I'm sure it's just spraying all over the inside of the bell housing and dripping out the bottom when I stop, but it seems to be getting worse.
Thanks again!
Kevin K.
I decided to pull the manifold and replace the lifters on Saturday. It was actually a very easy process. I inspected all the lifters and the cam lobes and all looked well. No dishing or scoring. It seems to run much better now.
I also picked up a real nice compression tester from my brother this weekend so I'll be checking the cylinders tonight.
Now I just have to replace the rear main seal. After taking the truck to the gas station and back, I parked it in the garage. In about 5 minutes I had a 8" dia. oil puddle. I'm sure it's just spraying all over the inside of the bell housing and dripping out the bottom when I stop, but it seems to be getting worse.
Thanks again!
Kevin K.
