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Engine noisier then normal?

Posted: July 3rd, 2010, 6:18 pm
by LetchcoreCJ7
Well I started up my stroker and have about 300 miles on it now. I am loving it! What a treat it is to have all the power and fuel injection in a CJ7. The idol is good as well.

One thing I noticed is that its sounds like it has a a little valve train noise. There are definatly no knocks or ticking it just sounds a little noiser then the V8's I have been use too. I did run the heavier Mopar springs, and a Mopar cam. Has anyone else experienced this?

Should I be worried or is there anything I should look into? I want this engine to last a long time. :cheers:

Re: Engine noisier then normal?

Posted: July 4th, 2010, 6:23 am
by gradon
Mine's noisier as well with the Mopar cam, lifters, and springs compared to the stock 4.0 valvetrain. It's at 25-30K.

Re: Engine noisier then normal?

Posted: July 4th, 2010, 7:26 am
by SilverXJ
The comp cam 68-231-4 made a racked. Every comp I had did that. Its the quick ramp rates. Tube style headers and roller rockers also contribute to the noise.

Re: Engine noisier then normal?

Posted: July 4th, 2010, 7:30 am
by LetchcoreCJ7
Thats what I figured guys! Its just good to hear others found similar noise. Did runing any kind of differnt oil help? Currently I am running 10w30 Penzoil.

Re: Engine noisier then normal?

Posted: July 4th, 2010, 9:29 am
by SilverXJ
No, oil changes did not help. You should be running an oil with high ZDDP content.

Re: Engine noisier then normal?

Posted: July 4th, 2010, 1:55 pm
by 6TIME
Back when the whole oil/zinc issue came to light, I switched to Rotella 15-40 from 10-40. After the oil change, My valvetrain was noticeably quieter than before with the noisy Comp 232-4 cam.

Re: Engine noisier then normal?

Posted: July 4th, 2010, 6:37 pm
by gradon
I thought roller rockers made the valvetrain quieter?

Re: Engine noisier then normal?

Posted: July 4th, 2010, 7:10 pm
by SilverXJ
No, they have a noise of their own from the roller bearings.

Re: Engine noisier then normal?

Posted: July 30th, 2010, 2:25 pm
by Hilljack
I think that we all need to accept that most of these are noisy and you'll find yourself spending to much time trying to track it down
My original 4.0 made considerable lifter noise and I had hoped that when installing my new stroker, this would go away. Nope - it was louder and I am finally going to associate this with the comp cam. Just Drives me nuts but what I have read on the forums, I might finally live with it.

Just to cover the some other things that contribute to the noise of the early 4.0 block (91-95), but did not fix it was -
1. Just installed some roller rockers to see if that would help - no noticeable gain.

2. Cracked headers - I have been through 4 of them, 1 stock, 1 Headman, 2 Banks. Currently running 3rd Banks. Really tired of changing this out! (If you get a chance install a flex section in your exhaust). Never install a wrap - just cracks faster and really bad.

3. Oil - I have tried going up and down in grade and found that 10W-40 Syn was the quietest that was tried but the difference are not far apart

Note - 97 and up blocks are quieter as jeep added more material to the block to address this. Listen to one stock.

I also believe in a good oil with high ZDDP as I ate a cam lobe off the stock motor at 114K. Ah well as it was a good excuse for the stroker.