Urban, FakeSnake or Anyone, Help

MonsterBilly · 01-20-2009, 03:59 PM

So i thought that my lifters were really loud. I started a thread and stating so and i was told to check my header bolts. I did and some of there were loose. I replaced the gaskets and drove the car. It was still ticking. i parked it and hadn't gone back til today. I drove it to get a soda and it was week.

I decided to pull off the valve cover and this is what i found on the #6 cylinder. The push rod is bent. Where do i go fom here and can the ralve be used. It is damaged on top where the rocker rides. It is worn at a small angle.

The motor is new and the guys that did it did a complete head job including valves springs and retainers with a port and polish.

do you think that i could replace the pushrod and re assemble it or is something like this require the head to be removed.

I hope the pics loaded

This ad is not displayed to registered or logged-in members.
Register your free account today and become a member on Mustang Forums!

urban_cowboy · 01-20-2009, 04:14 PM

I hate to say it, but I think at a minimum you are going to have to pull the head, replace that one valve, push rod, and rocker. The spring and retainer are probably fine. You cannot run it with that much damage to the valve stem.

You got to also wonder if the cam is ok since the push rod is bent.

Can you tell how this happened?

fakesnakes · 01-20-2009, 04:30 PM

Well, I'm curious about something. What cam are you running? You have rail rockers (rails on the sides of the rocker keep the rocker arm centered on the valve tip) and said you ported and polished the heads. This type of head used pressed in rocker studs. You really have to at least convert it to screw in studs or if you have a higher lift cam and stonger springs the pressed in stud will pull out of the block allowing the rail to slip off the valve tip and causing your valve train to make all sorts of noise. Please post more info about your rebuild (cam, head work done, valve springs, etc.).

I'm really sorry to see something like this happen to you and your fresh built engine.

fakesnakes · 01-20-2009, 04:34 PM

BTW, your damage is very typical of this issue. As the stud starts to pull out, the rocker gets loose and starts making noise. As it comes out further, every once and while the rail actually presses against the tip of the valve. This both damages the valve tip and the sudden added height of the rail causes the valve train to bind and the push rod bends.

urban_cowboy · 01-20-2009, 05:50 PM

Good point about the pressed in studs. If that is the problem, this could either be a fluke or the first of several stud failures. Either way, you may think about moving over to screw in studs.

I know exactly how it is to finish your engine build and then have head valve issues. I too am really sorry. At least you found a flaw and can fix it without a major catastrophe. That is never a bad thing or at least it could always have been a worse thing.

fast66 · 01-20-2009, 06:00 PM

Yep, As Fake says, press in studs are only suitable for absolutley stock engines (if that). As soon as you go with any performance mods, you should change to screw in studs. Did your motor come with a warranty? I would at least be going back to them and assking some pointed questions.
Interestingly, in late 66, the rail type rockers appeared. A common problem is that because they have shoulders each side of the valve to keep them lined up, as the valve wears, the shoulder thend to come in contact with the valve reatining collets. This causes them to release, and you drop a valve into your piston. BOOM
The early 66 had a much better system, where they had close tollerance push rod holes in the head (just like push rod guides) which kept the push rod aligned with the rocker, and so did not require the shoulderd rockers. Why they changed it I don't know.
Although your situation isn't a nice, I guess one positive is that as your press in stud has come loose, is has alerted you to this issue before more damage could occur.

BTW, are you sure your push rod is bent? Have you taken it out and rolled it on a flat surface, or are assuming its bent becasue the rocker is missaligned?

Cheers

MonsterBilly · 01-20-2009, 06:21 PM

Fast 66, it is for sure bent. I rolled it and it is for sure bent.

Fake
I called the builder and he asked me to bring the car in and he will fix it. He said that if i bring the lifter in along with the rocker he will give me replacements so i can assemble it and then drive the car to him. SHOULD IT BE DRIVEN EVEN AFTER A NEW ROCKER AND ROD IS INSTALLED?

So i paid over $500 for all the head work. I shold not be having this issue in my opinion. I m a business owner and if it were me i would feel compelled to do what it takes to give back a quality part/service. I hope that he will install screw in studs if that is what it needs.

I wish i would have bought heads rather than put the money into these.

Here is what was done to the heads:

magna fluxed to check for cracks
new intake valves were installed
new heavier springs (lunati)
new retainers (lunati)
port matched and trimmed removing excess material. I was there and watched this process
Polished intake ports

this is for the original 289, it has a lunati cam, stock lifters and stock heads
here is a link to the cam i have
http://store.summitracing.com/partde...K&autoview=sku

MonsterBilly · 01-20-2009, 06:24 PM

Is it possible to see the cam with a brite light?

fakesnakes · 01-20-2009, 06:32 PM

Quote:

Originally Posted by MonsterBilly

SHOULD IT BE DRIVEN EVEN AFTER A NEW ROCKER AND ROD IS INSTALLED?

Definitely not. The noise you are hearing is the rest of the studs pulling out and loosening up your valve train. That cam has a much larger lift than stock. Together with those springs, I'm suprised you made it 500 miles without a more significant failure. Since you already have so much invested in the heads, you can convert those heads to screw in studs by removing the stud, tapping the holes, and installing a correct screw in studs. I did it on my stock 1966 289 A-code engine with the heads installed. Unfortunately, the head with the damaged valve has to come off and have the valve replaced.

fast66 · 01-20-2009, 06:34 PM

So that cam has .522/.538 lift, which is much higher than stock. You may have experienced valve bind, where the amount of spring compression required is too much for the space provided. the usual proctice is to machine the spring seats to give more compression space. This will definitey bend a rod, and pull out your press in studs.
If this is the case, IMHO the heads need to come off and have the spring seats machined, and screw in studs installed. I would be very very hesitant about driving it at all.

The other thing that could have happened is that a valve has hit the piston. Do you have flat tops in there, or pistons with valve reliefs? Was a valve to piston clearance check done on assembly?
If this is what has happened, again, I wouldn't be driving it.