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Engine Help w/pics "Valvetrain"
2 Attachment(s)
Well i was cruising at about 3500 rpms when the motor started to miss it fell off plane. It didn't stall but it was knocking, I shut it down, got towed in. I got home and pulled the valve cover to find this on cylinder 3 and 5 the rockers arms are no longer on the pushrods yikes...it looks like cylinder 5 can just be put back on, but on cylinder 3 there is just way to much slack...The motor has about 15 hours on it and is a reman. the orignial was an 89' I know what it probably is but I guess I should as you guys...I am thinking cam lobe
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It could also be the rocker arm studs pulling out of the head....if they are pressed in, pretty common thing
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It looks like a catastrophic failure of cam. Pushrods more than likely popped out of lifter cups.
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Is that a tree-fiddy? where did the reman come from?
We just put a reman 350 in my buddy's boat. I'm hoping he fares a little better. That job SUCKED... I don't want to have to pull that sucker out again! In the second pic, it looks like the stud is pulling out of the head. |
i agree in pic 2 under the rocker it looks like the stud pulled out of the head
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Originally Posted by awsomethunder
(Post 2232270)
i agree in pic 2 under the rocker it looks like the stud pulled out of the head
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Its a reman 350 with vortec heads and an air-gap intake...it does kind of look like that (stud) I didn't notice it was any higher when I was looking at it last night but then again i didn't realize to look for that. I will lay a straight edge on it tonight when I get home. If it is the stud then how do I go about getting it out and going with a screw in?
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It is possible your rounded the cam or had bad lifters in the motor.
One way to check is to turn the motor over by hand and see if the lifters or pushrods are moving up and down. You can look into the lifter gally or just leave the push rod in place and watch it. Also check your pushrods and make sure they are not bent. |
thats my fear...I am praying for the easier of the 2...I don't mind removing the heads..but pulling the motor to change the cam would kill the rest of my summer!
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3 Attachment(s)
well it looks like the rocker arm studs are pushed out! what is my next step?
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If you just have a couple, you could pin them. I have done that in the past when I was poor.:D
If it was mine I would take the heads off and have them machined for screw in studs. |
To do it right you need to pull the heads. I don't know how old the engine is or if the heads were also new. If there is a warranty I would contact them and let them know of your problem that should not happen with only 15 hours on the engine. If you have no warranty I would install screw in studs.
I would also have the machine shop check all the studs if you choose not to install the screw in studs. You only want to do this once. Rob |
Formula,
Pioneer makes a repair rocker stud that is threaded on the bottom. It is not a performance type with a hex on it, just a straight stud with 7/16" coarse threads on the bottom. The existing rocker stud hole is the perfect size for the 7/16" tap. All you have to do is tap the hole (s) and install the repair stud. I think the part number is RM348, but if you call me on Tuesday, I will give you the number for sure. Real easy fix without pulling the heads. Bill Koustenis Advanced Automotive Machine Waldorf Md 301-843-5700 |
Originally Posted by BillK
(Post 2233573)
Formula,
Pioneer makes a repair rocker stud that is threaded on the bottom. It is not a performance type with a hex on it, just a straight stud with 7/16" coarse threads on the bottom. The existing rocker stud hole is the perfect size for the 7/16" tap. All you have to do is tap the hole (s) and install the repair stud. I think the part number is RM348, but if you call me on Tuesday, I will give you the number for sure. Real easy fix without pulling the heads. Bill Koustenis Advanced Automotive Machine Waldorf Md 301-843-5700 My father just did this to a friends 350 engine. 3 had pulled loose, so they used a type of puller to extract the rest of of the studs, and tapped all of them in an afternoon. Only had to remove the valve covers. Darrell. |
trh
that would be great....will my rockers work? and yea let me know where I can get them and what it will take!!
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You could thread the stud and tap the hole and just wait till the next one comes loose.
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Formula,
Your machine shop should be able to get them for you if they dont already have them in stock. I am almost certain that the Pioneer part number is RM348. I have them at the shop if you want to call me on Wednesday and I will gladly give you the number for sure. The most important thing is keeping the tap straight while starting it. Your rockers will work fine. Dont screw the new stud in too tight as it can split the stud boss if you aren't careful. Bill Koustenis Advanced Automotive Machine Waldorf Md 301-843-5700 |
It is quite possible the heads were baked and blasted to get them clean. It is very common to have stud issue after that. I have not been in the business for several years, but we used ti use .003-.005 oversize studs and loctite to repair them in the past, but is sounds like like the pioneer screw in repair studs would work just as well if not better. Just be sure you are not experiencing coil bind, or retainer guide boss interference that is causing the studs to pull out.
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thanks for all your help guys...I am going to call the machine shop today. I have one question though.
How do I install these new studs by pioneer? There is no nut to tighten? Should I install the rocker arm nut and use that to tighten? |
Originally Posted by formula18
(Post 2235642)
thanks for all your help guys...I am going to call the machine shop today. I have one question though.
How do I install these new studs by pioneer? There is no nut to tighten? Should I install the rocker arm nut and use that to tighten? I would use the 2 nut method (don't like the sound of that) tightning them together, and then torquing them to the proper specs. Don't forget the red locktite. Darrell. |
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