Broke a rocker Easiest way to fix? (pics inside)

[bmk]

I took off my valve cover to inspect what I thought was gonna be a bent valve and I find that one of my rockers sheered in half. Can anyone tell me what is the easiest way to go about fixing this?

[gtdragon980]

You'll have to pull the head unless you have a engine hoist. Then you can lift the engine up just enough so you can slide the rocker shafts out enough to replace it. The radiator and a/c components are in the way to pull the shafts out far enough if you don't raise the engine up.

[jlevie]

Yep, what he said. There is no easy way to fix that one. Even with hoist you may destroy the rocker shaft trying to get out since you can't drive the shaft from the other end. My advice is that you pull the head and rebuild it. One broken rocker means that others are likely to break, so you should replace all of them. I'd also have the valves ground and a minimal surfacing cut done on the head.

While high rpm operation increases the chances of a broken rocker, I've seen them fail on cars with automatic transmissions that seldom, if ever saw, the territory north of 5k. An the can fail on ETA engine with the 5400rpm limit. My theory is that a history of a lack of timely valve adjustments is the primary cause. The repetitive impacts from loose valves cause cracks to form.

[bmk]

Yep, what he said. There is no easy way to fix that one. Even with hoist you may destroy the rocker shaft trying to get out since you can't drive the shaft from the other end. My advice is that you pull the head and rebuild it. One broken rocker means that others are likely to break, so you should replace all of them. I'd also have the valves ground and a minimal surfacing cut done on the head.

While high rpm operation increases the chances of a broken rocker, I've seen them fail on cars with automatic transmissions that seldom, if ever saw, the territory north of 5k. An the can fail on ETA engine with the 5400rpm limit. My theory is that a history of a lack of timely valve adjustments is the primary cause. The repetitive impacts from loose valves cause cracks to form.

Thats exactly when mine broke, doing a high rpm pull...boo

[bmk]

You'll have to pull the head unless you have a engine hoist. Then you can lift the engine up just enough so you can slide the rocker shafts out enough to replace it. The radiator and a/c components are in the way to pull the shafts out far enough if you don't raise the engine up.

I have an engine hoist so that is no problem. Would you recommend taking out the drive shaft to get the most amount of raise. (taking out the ac/radiator is no problem ive replaced several m20's over the years)

[plmichal]

From personal experience.

I broke one rocker arm a few months ago and replaced it. A few weeks later, I was beating on my car again and snap goes another one. Just rebuild the head or buy one rebuilt. Much less hassle.

[jlevie]

From personal experience.

I broke one rocker arm a few months ago and replaced it. A few weeks later, I was beating on my car again and snap goes another one. Just rebuild the head or buy one rebuilt. Much less hassle.

Yep, when you break one, you will soon break another, and so on. Bite the bullet and rebuild the head.

Oh yeah, on a car that will frequently see the top of the rpm band, polishing the area of the rockers around the eccentric removes stress risers and reduces the chance of cracking. That and adjusting the valves every 10k should eliminate any future problems.

[e30leigh]

its shame. but its the truth. where theres smoke theres fire.... its just a matter of time till another fails now sadly.

but if you take out the rad, ac and front grill you can also get them out without lifting the motor. but its a real pain in the ass. you might as well take off the head. the work involved is about the same. good time to head stud it as well.

[TobyB]

I'd add new valve springs to the list of things to refresh while you're in there...

... after loose lash, that's a major cause of high- rpm failure.

t

[CHIF8008]

& valve keepers! never freaking re-use valve keepers. no need to drop a valve because you didn't want to buy "one more thing".

[gtdragon980]

I have an engine hoist so that is no problem. Would you recommend taking out the drive shaft to get the most amount of raise. (taking out the ac/radiator is no problem ive replaced several m20's over the years)

Personally, it would be more work to remove the driveshaft and what not to tilt the engine enough to replace 2 rockers. If you have the money, and want your car to be as reliable as possible, take the others advice and rebuild the head. And even if you choose not to, you can still remove the head, replace the broken rockers and replace the head gasket as it may not need it now but later on down the road it may.

Forgot to add, but I had two break on me once, but there were in the back of the head so I just replaced the two. Plus my engine has really low mileage so I think it was caused because of abuse, not wear and tear. In your case, if you have high mileage, just spend the money now and fix her all up!

[Maloney]

& valve keepers! never freaking re-use valve keepers. no need to drop a valve because you didn't want to buy "one more thing".

does this go for all valve keepers??

I thought the same thing man. But i have had my 1jz head taken apart and put back together, and ran again several times with reusing factory valve keeps and the machine shop never said a word or suggested that i get new ones....
and i was glad, expensive little fucks they are!

[bmk]

The motor was rebuilt somewhat recently, or so i was told. SO if i was going to replace just the rocker what parts would I need besides the rockers and HG?

[bmk]

bump

[jlevie]

The motor was rebuilt somewhat recently, or so i was told. SO if i was going to replace just the rocker what parts would I need besides the rockers and HG?

You will absolutely need head bolts, a timing belt/tensioner, valve cover gasket & bungs, exhaust header gaskets and new copper plated nuts, and oil return tube o-rings. While the head can be removed and installed with the intake and exhaust headers attached, that is really a two person or hoist job. If you remove the intake and exhaust you will also need gaskets and new copper plated nuts for the headers. It would be a good idea to also replace the cam seal and o-ring.