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Valvetrain noise, rockers or ???

RADO

Jr. Member
Joined
Sep 26, 2016
Messages
138
Loc.
Phoenix
I have a valvetrain noise on my 351W that I haven't been able to figure out. I'm looking for advice to point me in the right direction.

The engine is pretty quiet during cold start-up. Once the engine warms up, I hear a ticking coming from the passenger side valve cover area. The sound increases with engine RPM and I can hear a slight metallic ping in the passenger side exhaust. I've pulled the valve covers and adjusted the rocker preload using the method: loosen rockers until tick starts, tighten until quiet, put a 1/2 turn additional for preload. This process hasn't helped reduce the noise. I've also noticed that the rods will feel slightly loose again after I've just made the adjustment and the rockers almost feel sloppy when I rock them side-to-side.

I had a buddy look at the engine last week and he though the rods looked short, causing slop on the valve-rocker placement. He also suggested I look into roller tip rockers for a smoother operation. I found an article on checking rod length, which said to mark the valve with a sharpie and check where the rocker contacts the valve. I tried this method, but don't really know what to make of the results. Last two pictures show marking from test, thoughts?

The rockers look ok, the fulcums seem a bit worn. Should I spring for new rockers as a fix? It appears there are already 3/8" studs threaded in the heads. Worth going full roller rocker with hardened rods? or roller tipped rockers and check rod length? Or should I start elsewhere like lifters?

Video of engine running:
https://www.youtube.com/watch?v=3okydVMk4-Y
 

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bmc69

Contributor
Bronco Guru
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Jun 11, 2004
Messages
11,852
From some of your description it sounds like your lifters might be bleeding down too quickly. Any idea how many miles are on them?
 

JAFO

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Dec 3, 2007
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Loc.
Beaverdam
My 96 Dodge Ram 1500 has a bad lifter that will sometimes make a loud tick on start, then stop after a bit. Sometimes I can start it and the tick is really loud and take a long time to stop. Other times it quits really quick. I have been very lazy regarding fixing it and have put up with it for several years. Your description of the tick sounds like faulty lifter noise. They can fail and make noise cold or hot.

https://www.carsdirect.com/car-repair/how-to-tell-if-you-have-a-faulty-hydraulic-lifter
 
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RADO

RADO

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Joined
Sep 26, 2016
Messages
138
Loc.
Phoenix
Not too sure on the mileage on lifters, but the engine was rebuilt about 10 years ago and the previous owner didn't put many miles on the Bronco. About 20K miles in 16 years. The Bronco sat for a while before I bought it and the oil looked old. The engine has run strong for me the last year without much issue, but has always been a bit noisy.

Is it ok to replace lifters without replacing the cam?
 

73azbronco

Contributor
Bronco Guru
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Nov 11, 2007
Messages
7,796
Does not sound bad to me. Maybe thicker oil needed. STP will keep lifters from bleeding down. Valve stem seems oddly worn.
 
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RADO

RADO

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Joined
Sep 26, 2016
Messages
138
Loc.
Phoenix
Does not sound bad to me. Maybe thicker oil needed. STP will keep lifters from bleeding down. Valve stem seems oddly worn.

It's more the metallic pinging I hear in the exhaust, as i'm worried about engine damage if it's not a rocker noise. Which STP, oil treatment w/zinc?
 

73azbronco

Contributor
Bronco Guru
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Messages
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Metallic ping is preignition? Timing too advanced?

Uhhhhh, STP, They make more than one kind? It's been a few decades, sooooo.
 

Viperwolf1

Contributor
electron whisperer
Joined
Aug 23, 2007
Messages
24,316
Sharpie probably doesn't hold up to oil well. Clean the top of the valve stem, retainer and rocker off with brake cleaner, install and try it again by just cranking the motor by hand. A length checking pushrod would really help you see what happens when the length is changed and how it affects the contact on the stem.
 
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RADO

RADO

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Joined
Sep 26, 2016
Messages
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Loc.
Phoenix
I just picked up one of those adjustable push rod length tools and some roller tipped comp rockers. I figure replacing the rockers/fulcrums new will help eliminate variables even if it's not the fix.

azbronco, I shouldn't say ping as it implies timing. My base timing is set for 12 and I believe it's all good. The passenger side exhaust has a metallic noise I can hear at the tail pipe. I'll take a video next time I run the Bronco.
 

blubuckaroo

Grease Monkey
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Jun 11, 2007
Messages
11,795
Loc.
Ridgefield WA
Sometimes when you get an engine that hasn't had regular oil changes, the detergents in new oil will loosen up the old crud. When you start a cold engine, your oil can actually bypass the filter until the oil thins and the pressure drops.
The little piddle valve in the lifter can get crud in it and it won't seal properly.
I've had good luck spraying Berryman's Chemtool down the pushrod and pumping on the pushrod to get it into the lifter.
 
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RADO

RADO

Jr. Member
Joined
Sep 26, 2016
Messages
138
Loc.
Phoenix
Sometimes when you get an engine that hasn't had regular oil changes, the detergents in new oil will loosen up the old crud. When you start a cold engine, your oil can actually bypass the filter until the oil thins and the pressure drops.
The little piddle valve in the lifter can get crud in it and it won't seal properly.
I've had good luck spraying Berryman's Chemtool down the pushrod and pumping on the pushrod to get it into the lifter.

Good suggestion, I'll try using chemtool down the push rods when I work on the engine this weekend.
 

MonsterBIlly

Sr. Member
Joined
Dec 17, 2015
Messages
456
those do not look like screw in studs. they look pressed in! It could be a collapsed lifter. that is what it most likely sounds like.

My opinion is, if you can afford it heads and roller rockers.
 
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RADO

RADO

Jr. Member
Joined
Sep 26, 2016
Messages
138
Loc.
Phoenix
those do not look like screw in studs. they look pressed in! It could be a collapsed lifter. that is what it most likely sounds like.

My opinion is, if you can afford it heads and roller rockers.

I think they were already converted to threaded studs.

I'm going to replace the rockers, add some zinc, add some cleaner down the pushrods to lifters, and maybe go a little thicker on the oil. If the noise persists, I'll pull the intake and check out the lifters/cam. Stay tuned!
 

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bmc69

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I think they were already converted to threaded studs.

I'm going to replace the rockers, add some zinc, add some cleaner down the pushrods to lifters, and maybe go a little thicker on the oil. If the noise persists, I'll pull the intake and check out the lifters/cam. Stay tuned!

Yep..converted to thread-in studs.

Your plan is sound..good luck with it. There was a widespread issue with the quality of lifters being delivered about a decade ago and your issues might be related to that too. I ended up with at least two "noisy" sets and/or with one or two that simply would not fully pump up when I was building engines back then. The problem became widely known and I and other builders went to some lengths to find "NOS" Ford or earlier production aftermarket lifters to work around the problem.
 

DJs74

Bronco Guru
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Apr 1, 2014
Messages
1,135
Yes, what bmc69 said. I never had the problem but had some friend builders that did.

Also, if you go with roller rockers, don't be shocked if they are on the noisy side too. I've had roller tip rockers that sounded like solid lifters ticking. I've also had full rollers that make noise... its normal.

DJs74
 

broncomatt

Full Member
Joined
Dec 27, 2005
Messages
284
It does sound like a collapsed lifter, the give away was your saying it started off ok but as it warmed up it got louder. I just went threw this on a recent engine build. The cam and lifters were under summit racing warrenty. I had a long talk with trusted machine shop friend who builds drag racing engines. The lifter quality has been poor over the last few years. Made worse by the lack of zink in the oil out there. He suggested using a zink additive like lucus or something like it.
If you do go with roller rockers you still set the lash, Comp cams suggests tighten down till the push rod has slight pressure and then go 1/4-1/2 turn more. The machine shop friend states that would be around 30 thousands.
If your hearing it in the exhaust it probably is an exhaust valve.
 
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RADO

RADO

Jr. Member
Joined
Sep 26, 2016
Messages
138
Loc.
Phoenix
Thanks guys, I'm feeling a bit more motivated now to pull the intake and inspect the lifters. My weekend starts today, but I get to spend most of the weekend building a deck. Hopefully I get a little bit of Bronco wrenching time.

When I first noticed the converted studs, I got excited thinking about full rockers. I decided against for now, because I did read reviews that they can be noisy. The cost is also about double for brand name roller rockers. I really just want to resolve the noise issue and continue the "drive it like you stole it" mentality on my 351W Bronco. I was concerned about the current rockers and fulcrums, so I purchased these to start fresh:

compcams_magnum_rollertip_rockers.jpg
 

blubuckaroo

Grease Monkey
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Messages
11,795
Loc.
Ridgefield WA
Thanks guys, I'm feeling a bit more motivated now to pull the intake and inspect the lifters. My weekend starts today, but I get to spend most of the weekend building a deck. Hopefully I get a little bit of Bronco wrenching time.

When I first noticed the converted studs, I got excited thinking about full rockers. I decided against for now, because I did read reviews that they can be noisy. The cost is also about double for brand name roller rockers. I really just want to resolve the noise issue and continue the "drive it like you stole it" mentality on my 351W Bronco. I was concerned about the current rockers and fulcrums, so I purchased these to start fresh:

compcams_magnum_rollertip_rockers.jpg


There's nothing wrong with roller tipped rockers. especially if you don't use a high lift or roller cam. Those have lots more spring pressure.

But, you're gonna need to use rail type (self aligning) rockers with your stock head, unless you decide to use guide plates and hardened push rods.
https://www.summitracing.com/parts/cca-rp1431-16/overview/make/ford
 
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