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Recently picked up a pretty clean 93 Formula with 128k miles. When I got the car I found TONS of receipts from the previous owner dating back to 1999. Everything was documented from oil changes to a transmission rebuild and even a receipt from a shop who replaced the shortblock at 127k miles. That was a little over 5 years ago and it only has about a thousand miles since then. It looks like the previous owner used to daily it and then it became a spare / fun car for many years until he traded it in last year. A small mom and pop dealership got it from auction and it was making what they thought was some lifter noise. I snagged it from them for pretty cheap and tore into it. When I first got it off the trailer, this is what it sounded like:
I pulled the valve covers and when I got to the passenger side I noticed that the rocker for the exhaust valve on cylinder number 8 was just flopping around with no pushrod. The pushrod was laying sideways in the channel and I was able to fish it out. It was still straight and neither end was marred or chewed up. I also pulled the rocker to inspect for damage and it looked good as well. I went ahead and readjusted all the lifters and buttoned it back together. When I started it back up there was still a noise, just not as pronounced.
It sounds like it is still coming from the passenger side rear (cylinder 8), is it safe to assume there was probably some lifter damage due to the initial improper adjustment?
Exhaust leak with what sounds sounds like too much play on a lifter/rocker. Pull the valve covers first, take the rockers off and check for any abnormal wear on the roller lifters of the rockers and valve tips. If you don't know how to do so, you need to learn. Plenty of how to's. This one is the best: www.shbox.com.
If it were me I would yank off the manifold so you can get to the lifters. I'd pull each lifter one at a time and mark each one or place them out so you know which one went where. Inspect the rollers on them, see if they all roll freely or not and if there appears to be any abnormal wear. If you find any lifters that don't roll freely or have abnormal wear on the rollers, take a peak down their respective pushrod holes and see how the cam lobes look. I would also consider an exhaust leak as a potential culprit. I'd examine where the manifolds bolt up to the cylinder heads on both sides to see if any black soot is present. If you have access to a smoke machine you could perform a smoke test to see any smoke leaks where the manifolds bolt up.
Pull the intake and take a look.
Cool thing about these is you can replace the lifters without pulling heads.
The lifter would stay stay in place due to the spider And locators. (Maybe, worth checking)
Drop in some lifters and you could be done for under 150 bucks.
Yea, that's pretty much the plan now. Figure it can't hurt to pull the intake and take a closer look at the lifters. Thanks!
Originally Posted by SS RRR
Exhaust leak with what sounds sounds like too much play on a lifter/rocker. Pull the valve covers first, take the rockers off and check for any abnormal wear on the roller lifters of the rockers and valve tips. If you don't know how to do so, you need to learn. Plenty of how to's. This one is the best: www.shbox.com.
I thought exhaust leak as well after I had put everything back together, but all the exhaust manifold bolts are there and tight. I ran a mirror and shop light all around the manifolds looking for soot / leaks and did not see anything abnormal. I've had ol' ShoeBox's site on my favorites for years now, so I definitely went and checked there first for tips. Thanks!
Originally Posted by StealthFormula
If it were me I would yank off the manifold so you can get to the lifters. I'd pull each lifter one at a time and mark each one or place them out so you know which one went where. Inspect the rollers on them, see if they all roll freely or not and if there appears to be any abnormal wear. If you find any lifters that don't roll freely or have abnormal wear on the rollers, take a peak down their respective pushrod holes and see how the cam lobes look. I would also consider an exhaust leak as a potential culprit. I'd examine where the manifolds bolt up to the cylinder heads on both sides to see if any black soot is present. If you have access to a smoke machine you could perform a smoke test to see any smoke leaks where the manifolds bolt up.
Pulling the intake is definitely up next on my to-do list. I'd really like to get a closer look at the lifters and see what I can find. I looked for an exhaust leak after I had everything put back together, but didn't see anything suspicious. I'll look again while I'm in there though, just to make sure. Probably wouldn't hurt to put in new exhaust manifold gaskets anyways and make sure the bolts are torqued correctly. Thanks!
I thought exhaust leak as well after I had put everything back together, but all the exhaust manifold bolts are there and tight. I ran a mirror and shop light all around the manifolds looking for soot / leaks and did not see anything abnormal. I've had ol' ShoeBox's site on my favorites for years now, so I definitely went and checked there first for tips. Thanks!
My bad. Didn't watch the 2nd video. Still sounds valve train related. Shaking horribly as well. Perhaps a persistent misfire?
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