Cam Wear and Varnish

[Shellbird01]

Picked up a JK for cheap, good bones,130k miles, expected an engine swap, compression 140-150 psi. Pulled Driver head covers, rockers are like new, but holy varnish. Theres wear on the journals but lobes are fine. Thinking put it back together and take the time get a deal on a used. Any opinion on the wear? and how to remove varnish / clear oil passages?

All options appreciated

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[mwilk012]

what's wrong with the engine? Nothing there looks unusual.

 

[Shellbird01]

Thanks mwilk012, I expected at the price point the engine was likely toast, it had a misfire on cylinder 4, or at minimum a head swap but… The plugs were terrible, maybe original, cold compression is 140-150 and leak down on 4 was only 1%, will check the others. But so far so good? Next is to swap rockers on other bank.

Was just wondering if the wear and varnish was unusual, but from all accounts it’s pretty good. Fingers crossed.

Cheers

 

[Shellbird01]

I hear rocker tick but it wasn’t on the drivers bank

 

[Yawnie'sPapa]

130K miles? Really looks good for the age/miles. I'd nor worry about that small bit of varnish.

 

[Shellbird01]

Might do sea foam Before oil changes

 

[roaniecowpony]

If you have a lathe, I'd polish that cam journal with some 600 or 1000 grit...just a bit.

To me, the fact that there is varnish tells me he was using cheap mineral oil. Premium synthetics just don't look like that. I'd put in some premium synthetic oil, like M1 Extended Perf, M1 ESP, or Pennzoil Ultra Platinum, etc and do some quick oil changes ~1000 mile along with oil analysis. Check the timing chain tensioners for wear before you put it back together.

 

[mwilk012]

If you have a lathe, I'd polish that cam journal with some 600 or 1000 grit...just a bit.

To me, the fact that there is varnish tells me he was using cheap mineral oil. Premium synthetics just don't look like that. I'd put in some premium synthetic oil, like M1 Extended Perf, M1 ESP, or Pennzoil Ultra Platinum, etc and do some quick oil changes ~1000 mile along with oil analysis. Check the timing chain tensioners for wear before you put it back together.

Yea thats plain old conventional but nothing wrong with that per se, its not damaged by any means.

Are you having problems fixing the misfire? Seafoam in the oil might help clean it up a bit but I wouldn't expect a performance change from that. In that video all I can hear is wind noise and injectors. Nothing concerning.

How persistent is the miss? Injectors were bad on these. 12-13 ohms is normal resistance. I'd check that.

 

[The Last Cowboy]

I’d use a full synthetic high mileage oil. It will keep the seals, gaskets and O rings from getting hard and brittle. Also has a little more cleaning ability.

Before I clicked on the thread, I was expecting bad pics, but those look good. Much better than an engine with factory spark plugs should. You will prob get some carbon burn off after you install the new plugs, so be prepared for that. Drive it hard for that first 1k miles before you dump the oil. At oil change time, check the plugs again, they may need some carbon cleaned off.

 

[Shellbird01]

Yea thats plain old conventional but nothing wrong with that per se, its not damaged by any means.

Are you having problems fixing the misfire? Seafoam in the oil might help clean it up a bit but I wouldn't expect a performance change from that. In that video all I can hear is wind noise and injectors. Nothing concerning.

How persistent is the miss? Injectors were bad on these. 12-13 ohms is normal resistance. I'd check that.

I assumed given the mileage and history with the pentastars some lifters would be bad,. Not sure how persistent the misfire is but given the history with the driver side head cracking eg 10 year 150k mile warranty, that’s where my mind went. I’m happy to be wrong on all accounts.

I was considering new coils / injectors onthe drivers bank only to avoid pulling the plenum again, then decided to swap #4 coil / injector with #1 for ease of access, but wasn’t aware of injector history, appreciate that info ???.

I was also interest in checking for loose oil galley bolts and worn cam phasers but no issue in the drivers bank either,

Thinking now not to bother the passenger bank af all,,,,

 

[Shellbird01]

I’d use a full synthetic high mileage oil. It will keep the seals, gaskets and O rings from getting hard and brittle. Also has a little more cleaning ability.

Before I clicked on the thread, I was expecting bad pics, but those look good. Much better than an engine with factory spark plugs should. You will prob get some carbon burn off after you install the new plugs, so be prepared for that. Drive it hard for that first 1k miles before you dump the oil. At oil change time, check the plugs again, they may need some carbon cleaned off.

I run mobil 1 full synthetic extended and m1 filter on all machines with 5k mile interval. Pensoil full Syn was on sale so I used that for lifter swap and intend to do and oil change now and at 1000 miles.

Apprecate the heads up on Pulling the plugs, you clean them in any special way?

 

[Shellbird01]

If you have a lathe, I'd polish that cam journal with some 600 or 1000 grit...just a bit.

To me, the fact that there is varnish tells me he was using cheap mineral oil. Premium synthetics just don't look like that. I'd put in some premium synthetic oil, like M1 Extended Perf, M1 ESP, or Pennzoil Ultra Platinum, etc and do some quick oil changes ~1000 mile along with oil analysis. Check the timing chain tensioners for wear before you put it back together.

How would I check tension wear? You mean the guides I assume?

 

[The Last Cowboy]

Apprecate the heads up on Pulling the plugs, you clean them in any special way?

I just use a wire brush and brake parts cleaner.

 

[Shellbird01]

If you have a lathe, I'd polish that cam journal with some 600 or 1000 grit...just a bit.

To me, the fact that there is varnish tells me he was using cheap mineral oil. Premium synthetics just don't look like that. I'd put in some premium synthetic oil, like M1 Extended Perf, M1 ESP, or Pennzoil Ultra Platinum, etc and do some quick oil changes ~1000 mile along with oil analysis. Check the timing chain tensioners for wear before you put it back together.

I pulled the bearing cap tonight and it cleaned up nice with emery cloth

 

[Shellbird01]

Yea thats plain old conventional but nothing wrong with that per se, its not damaged by any means.

Are you having problems fixing the misfire? Seafoam in the oil might help clean it up a bit but I wouldn't expect a performance change from that. In that video all I can hear is wind noise and injectors. Nothing concerning.

How persistent is the miss? Injectors were bad on these. 12-13 ohms is normal resistance. I'd check that.

11.9 ohms on bank 1 injectors, think I should do new coils?

Spark plug tips were quite worn

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