Broke a rocker arm, replace the springs?

[Mossman]

Yes the springs like all things steel will experience fatigue/creep. The spring rate will be lower as the springs wear as well, raising the chance of valve float occurring. That being said I romp on my 200k mile valve springs to redline all the time and don't worry about it. I've never had a rocker randomly break unrelated to a timing belt snap, but I know it does happen. If it was me I would have yanked the head the 2nd time a rocker broke, and rebuilt it. Definitely wouldn't have swapped single rockers 4 times that sounds miserable. Granted, valve springs aren't an item I would normally replace in a stock rebuild, but a capable machine shop ought to have a way to easily test spring rate of your springs. Without an acceptable stock range to compare it to, that doesn't mean much, but buying one new inner and outer in order to compare is pretty cheap.

TLDR: Make sure you're adjusting your valves properly and often enough, your timing is correct, and if another one breaks get some new springs.

[wakeboardr42393]

Do valve springs wear out over time? That is my question. I've heard people say they will be fine, and I've heard others say they won't. Who is right?

I am replacing my FOURTH rocker arm on my m20b25. The engine is stock for all I know. The same one has not broken twice so maybe the rockers are just old. But then again, only the intake rockers have broken so far. and I know the intake valves are bigger, therefore heavier, then exhaust valves. are they floating? could they be floating bad enough that the valves would be hitting the piston, sending a shock back to the rocker, breaking it? if so, I don't want to just replace rockers to risk messing up the way the valves seat. like i don't want to ignore the real problem by just replacing rockers.

I beat the crap out of my car and frequently bounce off the electronic rev limiter. All four times a rocker has broken, the engine was at 6500 rpm at the time of breakage.

I plan to race my car within the next year (stage rally), and I figure if something can't handle "spirited" street driving, it will not handle racing. kind of working the kinks out lol.

the engine has unknown mileage (bought the car with non-working speedo/odo, since fixed.). If the rockers are breaking consistently, I don't think it is a fluke. It seems like something is wrong. I thought these engines should be able to handle being at the redline often? The reason I bought an e30 is so i could run it hard? (well, there were more reasons, but this is just one of of them ;] )

I have not pulled the head, it is not too bad of a job with the head on the car- takes me a few hours by now lol. i have a thread with some photos of me doing the rocker while the head is still on the car, if anyone is interested haha.

So, can the valve springs be so worn that it would be worth replacing? I really don't know about the properties of springs and metal etc.

[CrazyJew89]

stock i springs are fine till like 7200rpm you should have no issues with valve float as you shouldn't be reving that high in a street m20. also make sure you adjust your valves thats probably the reason it broke do that and you should be fine.

I assumed the stock springs would be good a little past red line but i guess my question is does that 7200rpm drop w/ age, and if so is it enough to justify buying some cheap newer springs from someone on the forums? Actually I checked the valve lashings a couple days before this happened.

I would at least get a standard valve job and have the head checked out like J Levie says. The machine shop will probably recommend you replace them. If they have 180k and were abused like you say, they are probably tired. Then again if you just need this car to get you from A to B and don't care about keeping it, maybe don't bother.

I am not going to take it to the machine shop b/c it is currently a really fun A to B car, I'm a college student that doesn't have a huge budget, and it ran perfectly fine before the rocker arm broke.

I think it is silly to pull your head to replace all your rockers. I think if you have a good 180K motor, just fix it and drive it until it wears out, THEN pull and apply the love.

I think it is too but unfortunately it was on cylinder 4 and from what I have read you can't easily fix that without pulling the head. Besides, I already took it off.

[StereoInstaller1]

replace worn part #m20 with freshly rebuilt part #m50 or higher.

blah blah replace motor blah blah

[monkeytaco]

So I broke a rocker arm the other day and I am taking the head off to replace all of them, seeing as this car was abused in the past. However I am not sure I am not sure if I should be replacing the springs as well. The reason I am questioning the springs is b/c everyone seems to like to bring up valve float all the time. The car has 180K and was running perfectly fine before the rocker arm broke. What do you guys think?

replace worn part #m20 with freshly rebuilt part #m50 or higher.

[StereoInstaller1]

I think it is silly to pull your head to replace all your rockers. I think if you have a good 180K motor, just fix it and drive it until it wears out, THEN pull and apply the love.

[lennon]

I would at least get a standard valve job and have the head checked out like J Levie says. The machine shop will probably recommend you replace them. If they have 180k and were abused like you say, they are probably tired. Then again if you just need this car to get you from A to B and don't care about keeping it, maybe don't bother.

[jlevie]

If you are going to remove the head and replace rockers it would make sense to complete the job by having new guides installed, valves ground, new seals, and springs checked. You should have have the cam gaged to see if it is worn below spec.

[SmokeE30]

stock i springs are fine till like 7200rpm you should have no issues with valve float as you shouldn't be reving that high in a street m20. also make sure you adjust your valves thats probably the reason it broke do that and you should be fine.

[CrazyJew89]

So I broke a rocker arm the other day and I am taking the head off to replace all of them, seeing as this car was abused in the past. However I am not sure I am not sure if I should be replacing the springs as well. The reason I am questioning the springs is b/c everyone seems to like to bring up valve float all the time. The car has 180K and was running perfectly fine before the rocker arm broke. What do you guys think?