Not a cracked flexplate?
Urgent help needed - Ticking Chrysler 4.7
- Thread starter TheSavage4.7
- Start date
Please! Don't take the engine out and replace it entirely with a crate engine yet. Fix the exhaust leak. As sure as i'm attempting and struggling to spell works on this device here and now, I'm sure its causing some of your issues. I kid you knot, I have had an exhaust manifold leak tick. chirp rattle, chatter and gurgle. especially with the newer MLS gaskets. Please fix what you know is broken first. Frankly, It just makes the most sense to me now when it didn't to me then, which it where your at now. Right?.
Could be a bad seal or cracked or warped manifold or broken stud still held in the manifold.
Now that you believe it is an air leak, my next step would be to locate the leak. Get a length of 3/8 copper tubing (to be bendable) and probe that area of the engine listening through the tubing. Sparkplug area, head gasket, and especially exhaust manifold. When you get close to the leak you can hear it clearly thru the tubing. If it is a leak that you can hear while cranking it should be easy to find while running. Given the correlation with heat I'm putting my money on exhaust manifold even though it looks good.
I wondered if the timing chain tensioners aren’t putting enough tension on the chain till it warms up. Also I also had the thought of the exhaust leak getting worse. As far as the lower compression on #7 you could do a leak down test to pinpoint it. Try posting this in the repairs section at:
www.allpar.com
www.allpar.com
I believe You answered your question here. With the spark plug out and no where for the compression on number 7 to go other than the plug hole, no noise. you have an exhaust leak on cylinder number seven going somewhere. or something in the rotating assembly. Rod wrist pin piston skirt? however these would more a knock than a tick
You said you changed the lifters and rockers. If your oil pressure is good, than they should be pumping up unless something is clogged in this area. You cold run the engine with the valve covers off and see if the oil is flowing around all of #7 rockers and lifters. Messy yes. You could try to take out the #7 spark plug Take off the oil pan again and unbolt #7 rod from the crank. check the bearing, Push the rod up in the bore and check for play in the wrist pin. if this looks fine, check drive it as is until it comes apart or pull the engine and do a rebuild. Yes from what I've heard, these engines have a history of bad oiling. Good luck
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The engine has VERY strong old pressure. I’ve ran it with the valve covers off before, and within 5-10 seconds of it running oil was pretty much shooting out from the lifters/rockers. Oil pressure is definitely not an issue, but i need to check on the wrist pin for Cyl 7. That is what i think it could be.
Im going to do this tomorrow then.
The engine has VERY strong old pressure. I’ve ran it with the valve covers off before, and within 5-10 seconds of it running oil was pretty much shooting out from the lifters/rockers. Oil pressure is definitely not an issue, but i need to check on the wrist pin for Cyl 7. That is what i think it could be.
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There is also 0 blow by in the engine. When i put my hand on the oil cap when its running it sucks my hand just a tad bit, but absolutely no blow by.
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Not going to drop a crate engine into this any time soon, lol. At least not until the block is too damaged to be repaired, which from what i could tell, is not the case here. I’d rather throw in a set of new heads. Manifolds for the Corsair 4.7 are nearly impossible to find. Chrysler decided to change them up from 08+ and they haven’t been produced in 10 years.
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The compression in cyl 7 is lower, but it’s still within the 25% variation range Chrysler has out for this engine. The highest cylinder is 145 PSI. It sounds more like a metal scraping noise when i listen to it with a mechanics stethoscope. It is VERY noticeable on the EGR piping that runs up to the intake, and very noticeable on the exhaust manifold on cyl 7 and on the block in that area. I checked again for cylinder damage with a camera and there is none.
Here is a nice smoke machine that works well for not that much money. I have it and also their Ventus model which uses a rechargeable battery.
www.autolinepro.com
The cadence of your clear flood crank still sounds a little off to me which could reflect a compression issue. I regular compression test will not always show a clear problem. Schrodinger's box on YT has several videos about this. He uses an in-cylinder transducer to definitively show that there is a compression problem. He talks about it and shows the in cylinder test in this video.
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The cadence of your clear flood crank still sounds a little off to me which could reflect a compression issue. I regular compression test will not always show a clear problem. Schrodinger's box on YT has several videos about this. He uses an in-cylinder transducer to definitively show that there is a compression problem. He talks about it and shows the in cylinder test in this video.
If it was me, and its just the wrist pin with no option to pull the engine, Just pull the head and push out #7 piston with a pipe and replace it and the rod. You may have balance issues depending whether the replacement parts are OEM or not. You will have a ridge on the top of the bore from wear. This will need to be removed with a reamer and this may be able to be rented. some say leave it there but a new piston with a new set of rings will travel ever so slightly higher in the bore, When the new ring contacts this ridge, bad things can happen, right. Wrist pin rarely fail before other wear surfaces. Rings need to be gapped, Cylinder honed to break the rings in, Not a easy proposition man. I give you credit for your efforts.
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I know wrist pins rarely fail, which makes this matter even more confusing to me.
I don’t understand how a wrist pin could just randomly decide to break overnight with the engine off when it ran just fine before. It still runs good, but due to the tick, the knock sensor is advancing spark timing to over 40° and causing the short term fuel trims to hit -13 across both banks.
If that somehow is the issue, and i’ll find out later today, I am probably going to find out a way to pull the engine and drop a new one in. This truck was my DD, and since it started this i had to quickly slap together my project car and drive that, which i absolutely hate. If it isn’t a wrist pin and the noise is coming from some sort of mythical void i’ll just drive it till it shoots a rod.
I 100% agree
