Head returned with concerns

[barishiman]

I went back to the machine shop today and finally got my head back. Here's what went down:

The machinest replaced 4 exhaust valves instead of the initial two. Reason was that the valves were bent. He explained to me that my rockers could be off (moving diagnolly instead of up and down) causing the valves to bend. I did notice some wear on my rocker arm shaft when I disassembled it for cleaning. Some of the rockers had to be forced off and on the shaft. He's quoting roughly $180 for a new shaft and rockers.

So, what do you guys think. I'm looking for a second opinion. Also, what other rocker assembly could I look at if replacement is necessary?

Thanks again!

 

[CobraSix]

Is it a stock non-adjustable rocker shaft that came with the 200? If so, definitely ditch it.

Several options:

Cheap: A stock adjustable from an early 170/144CI engine. Look on ebay, usually go for around $50 or so.

Better: A stock adjustable rocker shaft, and MIke's roller tipped adjustable rockers ($50 for shaft, $325 for rockers).

Best: Mike's Fully adjustable roller tipped rockers, $385

Real cheap...I may have a stock 200 non--adjustable rocker assembly you can have real cheap. Unfortunately, unsure of condition and don't know if it will help your problems.

The problem with non-adjustable rocker arms is that if the arms are off a little, then you put a lot of diagonal forces on your valve train causign excessive wear.

Personally, if you have the money, now is the time to spring for one of Mike's set ups. If you already have lifters and pushrods, the roller tipped rockers are your best option since you don't have to replace your stock lifters and pushrods.

Slade

 

[Junk-Falcon]

IF

 

[AzCoupe]

I have a rebuilt stock adjustable assembly (non-roller) that I will sell fairly cheap. Can't remember what I paid for them off the top of my head, but I can find out when I get home tonight. I think it was about $150 IIRC. Will post pics too if you want to see them.

 

[Anonymous]

I might need them...

I cant seem to finalize things to sell my car. I have a valve tap...which the asshole mechanic guy did not address. I cant keep taking it there...

I need it to be done.

how hard/easy is it to replace the stock rocker shaft? or maybe its just a spring...but I might delve into this myself...

so how much for that assemby, AZ?

 

[CobraSix]

Rocker shaft is real easy to replace. I think it is like 4 bolts. It's just a matter or adjusting the new one when you get it, and that isn't very hard either.

Slade

 

[barishiman]

I have the adjustable rocker arms with hyrdualic lifters. The rocker assembly is stock, except the rocker shaft (I think).

 

[Falcon62]

If you just need a rocker shaft, try Gary at Rocker Arm Specialties, shouldn't be much.

 

[AzCoupe]

I was wrong, I thought they were adjustables, but they are not. Here's the pics of the stock assembly and of a roller tipped assembly. Both were made by R.A.S. I'll sell the stock set for $65.00

 

[rbohm]

8) andrew i have a set of rockers on the 250 i bought for my falcon. i am not sure how good they are, and dont know if they are adjustable or not, but you can have them for the price of shipping.

 

[Anonymous]

you say they are easy to adjust? could that be what is wrong with mine?

here's what is happening...sometimes...only sometimes...I get a metal-ish sounding tapping...

its started after my vavle job...and I am hoping it is just a rocker adjustment...

so I should take off the valve cover and then...what? how do you do an adjustment?

sorry to be such a novice about this...but this is how you learn..by fire
chaz

AZ...if I need to replace it, I'll let you know...

 

[falcon fanatic]

Rocker arm specialties also sells stock adjustable style ratio rockers for $170 complete. That seems like a great upgrade for the price, although I would go with mike's rollers if I could afford it...

www.rockerarms.com

 

[addo]

OK, valve stems can be bent by misalignment, but more likely mishandling. Before the head goes on, you should check for free movement of each one by depressing it with the palm of your hand on top of the valve. Be sure to push in line with the valve, and check movement over ½" or so. It should be hard to push, but smooth, with a positive return to the seat.

Please check that timing chain slop again. I know it's unlikely things skipped, but better safe than sorry.

Rocker arm wear can be fixed. Unless the shaft wear is causing significant side-side slop, or oil loss, don't fret. More of a problem is when the tips do not match the valve stem tips. Your stem tips should have a very fine ground finish. The arm tips should be ground smooth to reseat on the new stem tips. The "cheats" way is to linish them all mounted on the shaft. It works, but I prefer to smooth with an oilstone and paraffin after.

When reassembling the rocker gear, ensure the pushods are first properly seated in the lifter cups. A dab of assembly lube helps stick them in. Similarly lubricate the rocker tips, valve stem tips, and ball/seat on the pushrod tops.

Lower the shaft onto the top of the head, engaging all the pushrods in the arms as you go, and starting the pedestal bolts into the threads. As you tighten these bolts evenly and progressively, check all the time that the pushrods are still sitting properly. Having the motor at TDC#1 compression is a good point to install the head, as you can begin your adjustment straight away. Torque the pedestal bolts to spec, and look for excessive valve depression (indicating something amiss).

What people seem to miss on the valve adjusting side, is that the drag/resistance initially sought is almost imperceptible. Especially when the gear is all sticky with assembly lube. Rather than trying to rotate the rod, perhaps the novice is better trying to jiggle it up and down. Initially it should be slack such that there may be 30 thou of "easy" totally free movement in this way. Then adjust the nut one turn.

Yes, this way may render it loose shortly, but better to spit a pushrod than bend a valve. Not that it's likely. The engine should now run, and after a "break in" to match the rocker tips to the valves, you can readjust.

Regards, Adam.

 

[barishiman]

I've gave the rockers some thought and with all the money I've put into the motor I might as well upgrade the rockers while I'm at it. I'm thinking about a set of Mike's roller rockers. Adam, I'll follow your guidelines once I get the new rockers. Ah, getting the new rockers is a different story...

 

[Anonymous]

Hello there Andrew.

Man I wish things were going better for you...

Mike's Roller rockers are a nice addition, and worth the price...
here are the other things you MUST do first and consider....

1. You must change to oil through lifters and rods which is really no big deal but a factor to consider, and you have to get the right length rods for your buildup... your machinist can probably help you out there... (so can Mike I am sure...) I used slightly shorter rods, but I decked 30 thou off the block and milled the head.

2. You must also plug the oil galley shaft hole that comes from the block to the head where the old rocker shaft took its oil... I ended up tapping and plugging this on the head, and I have had no problems yet, but the best method would be to plug the block thus reducing the chance of oil leak around the gasket... (we also put a little sealant around the hole on the block to help out) and no leaks...

That was it as far as what I encountered with mine.
I did not have to shim the rockers, the height of the plate was perfect, and I could adjust them the rest of the way and the geometry looks good.

I have learned a lot about rockers and valves, these past few weeks... and I can tell you I like this addition to the engine... besides the reduced wear on the valves, which is great, having created a high RPM 200 this was almost a necessity!

Plan on an extra hundred bucks for the lifters and rods... you can spend more maybe even less.... mine were about 210.00 for both... but I went all out on the rods!

 

[barishiman]

I didn't get the head decked, but the machinest did say that he resurfaced the head incase of imperfections from the past (guessing that was milling the head?).

I know I have the ball and cup design pushrods. I am planning to take some pics of my rockers and to show what I do have.

Why is it necessary to plug the old rocker shaft hole for oiling?

Don't you want the rocker arms oiled at all times so there is no friction?

Is it possible to just bolt on the roller rocker arm assembly without plugging the hole?

Also, if I did purchase new lifters, would that affect the wear on the cam in any way? (not wanting to buy a new cam if I don't have to)

I don't want to dive deeper into my pocket because of not knowing all the bases and something breaking after I just got it fixed. I'm in no big hurry, but the way it looks, it won't be until next year before I can really work on my car. I'm working 6-7 days a week and 4 days I have school to attend between working. I just don't want anything to go wrong anymore. And yes I have had thoughts of just getting rid of the Mustang for good like driving it off a cliff. But I know I won't, it's my first love.

 

[Anonymous]

This is only for the Full Roller Rockers.. because they do not mount on a shaft but seperately on a plate... the oil shaft is eliminated.

because of this you have to use lifters and rods that pass oil up through the crank and then through the lifters and rods to the rockers... they have holes in the center that allow oil to move through them. The rods need to be ball and ball type rods... no cups.

This sounds more complicated than it really is...

then once you have the right lifters and rods in place you need to plug that old passage into the rocker shaft that is no longer there... otherwise oil will slush out all over the place and you will not have the pressure to push it internally.

We simply tapped the hole in the head and plugged it. No worries!

As for the lifters and cam question I cannot help you there... although I would think you could change lifters and not the cam... but not the other way around? best to let someone else chime in here!

Here is a closer look at the mounting...
<img src=http://www.image-hosting.net/images/messageboard/jbowhall/DSCN0420.jpg>
<img src=http://www.image-hosting.net/images/messageboard/jbowhall/DSCN0411.jpg>

 

[addo]

New lifters on old cam - no problem! Just break in like a new cam, with cam lube. Other way round is not so clever or predictable.

 

[barishiman]

I must be confusing myself again, I am wanting the roller tipped rockers not the full roller rockers. Sorry about that. So thus implies the same questions as before:

Why is it necessary to plug the old rocker shaft hole for oiling?

Don't you want the roller tipped rocker arms oiled at all times so there is no friction?

Is it possible to just bolt on the roller tipped rocker arm assembly without plugging the hole?

 

[Anonymous]

None of this applies to the tipped rockers as they mount on a shaft just like the stock ones... so you are set to bolt them on and adjust them as is... keep your lifters and rods (although you might need different rods depends on the contact points as to if they need to be cup or ball...) well fromt the looks of mikes post you will need ball and ball rods, but solid ones.

my comments were for these rockers only...

You are all set to insall those on your current setup and not need to make these mods.