I had my Pro magnum roller rockers installed last week. Since I got the car back it is hard to start when cold. It seems to be getting worse. Starts then dies right away. Tonight it starts on the 3rd try....but was wanted to die as i backed it out of my garage. After 5 mins or so the idle improves ....everyhting settles down...runs perfectly.
This is a car that always started on the first shot and had a nice steady idle during the 3 min "warm-up" before taking off. What the hell? I am not happy with this. Anybody have any thoughts?

 

Rocker arms tightened too tight. I messed around with preloads just this week on my car and found what was too much and too little, too much and starts wouldn't happen, even when hot, until at least the fifth turnover.

 

Also, when the valve covers where taken off, they possilby diconnected vacuum lines and electrical connections. Check to see if everything is back in place. If so, may need to disconnect the battery a few minutes, to reset the computer.

 

Thanks, guys. I will check it out. I really hate when u get something done to improve the car then it seems as though there is a problem. It ruins the moment. If u know what i mean.

 

I disconnected the battery and checked to make sure everything was cool.
I was hoping...i mean really. No change. F:::K! Now I have to take it back to the shop. I don't really have time for this but hey i cannot stand having it barely start like this. Thanks again for the info.

 

It sounds like Slade is right. Your valve lash is to tight. Valves are staying open. Therefore no compression really. Yeap take it back to the person who installed them. They shouldn't charge you. But definatly check for vac leaks too before you go complaining to the installer. Just to be safe. He may have knocked something of by accident.

 

??? how do you check for vac leaks? Please give me detailed info on what to do and what to look for. I checked all connections around valve covers. But honestly I am not sure what i was looking for.

 

Vac leaks can be hard to find. If all the vac hoses are connected, I would just take it back and let them know of your problem. Be nice at first and mention a leak or the valve lash is to tight. If they screw you around, let us know and we will give you the proper lingo to put a plug in there bullsh$t. See what they will do for you first. Be nice though...it usually works with honest mechanics.

 

If there is a vacuum leak anywhere usually the idle stays high. Figuring out where the leak is occuring is something that is usually just done by ear.

 

Sorry...but what is a valve lash? Do the valve covers have to come off?

 

Yes the covers do have to come off. How to word this? This is basically the adjustment of the Valves. You want the valves to open and close perfectly. Valve lash... If the rockers are over tightened, the valves may not close completely or properly. If under tightened they don't open enough, not allowing the A/F mixture to enter the combustion chamber smoothly. This can cause misfires, backfires, I think even detination. It also can cause the engine not to start if it is way off. Both the intake and the exhaust valve have different specs, depending on your cam. I suggest you take it to your mechanic, or a friend with a bit more knowledge. Pay close attention though, consider it a learning experience. With stock rockers, to start off. I generally tighten all till I see 4 threads, the push rods should feel snug but still be able to turn them. Now with roller rockers this probably won't help you. Like I said take it to your mechanic or a knowledgable friend, again pay good attention. This way you know what to do next time. Hope this helps.

Keiran

 

Thank-you....The more $ i spend....the more I learn.

 

Well Yeah I guess? Anything that is more simple you should try to do yourself. This time you will need some help. Next time you shouldn't. If it is the valve lash that is out, the person who put it in for you should do it for nothing. It was his/her mistake to bgin with, unless you didn't give them your cam specs. Anyway no thanks is needed, Just glad to help.

 

Kaz depending on the length of your thread for the rockers, 4 threads may be too much.

Too much preload and your valves may not close properly since the rocker arm is lowered into the spring causing the valve spring to compress. This happened as early as 3 threads on my rocker arms.

I admit, your 350 seemed a little anemic and if that's the way you tightened your valves, this could be the reason why.

I found on my stock heads zero lash was at 2 threads.

The technique I ultimately used was loosening the rocker arms while the engine was running till I heard clack and then tightened them accordingly till the clack went away then gave a 1/2 turn of preload on them.

 

Actually. That is what I did! I just used the 4 threads as a start point. Then did just as you described. I however did find a problem last night. The one runner is sucking air. Not good! The only reason I did not continue describing what you just have, I did'nt want to give Luva to much info to take in at once. I thought it would be better for him to get help doing it the first time so he could see just what to do. The air sucking runner was causing that popping sound. To late to fix it now. Taking her apart to begin her updates.

 

luva is a she not a he

 

so luva, need help with that valve lash problem?

its sorta turning into my weekly thing.. 2 friday's ago, help with alternator swap in parking lot.. last friday help with tuneup... last saturday help with rad change... I just did my rocker arms recently with the same rocker arms too

 

Thanks for the offer. As of today the place i had it done it going to see the car at the end of the week. I really hope it is minor and quick??
I used to live in Brampton. Williams Pkwy/410.
Where are u ?

 

Actually just 1 exit north lol, Bovaird/410.

Rocker arm adjustment is quick, depending on if you have A/C and/or smogbox or not...

Another thing is the person adjusting it, if they don't have a general idea of how to do it they can easilly add too much preload thus giving harder starts.

For stock heads, 2 threads and already at 0 lash. Another matter is adjusting them cold. The plungers depress to to lack of oil pressure and what ends up happening is yeah you can still rotate the pushrods and then you get a big mess on the preloads with different preloads on all rockers.

 

I'm sorry, I didn't realize. Most females let us know somehow. again sorry. And if I didn't say this before...Welcome to the board. I guess I would have known if I checked your profile. My fault.

 

<==is a he



Now that we're formally introduced...






Welcome to the board!!!




PS... REMOVED BY MODERATOR FOR LACK OF TACT Paul_Hughes_87 T/A

 

Thanks 4 the welcome. I find this board pretty entertaining at times!
I do a lot of cruising to different areas....so if you see me honk. Car:red 88 Iroc.....driver: blonde woman.
My cruising may be coming to an end soon. I saw flurries last night!
I do not drive my car in the rain or snow. My paint is original and still looks great....so I must preserve.

 

Note to self, cruise around Etobicoke looking for 88 Red Iroc with a blond woman for a driver... hehe

Note to self honk then introduce self