Novak Conversions Jeep Wrangler TJ engine mounts

4.0 cylinder #3, bent spark plug, oil smelling like fuel, knocking noise after engine swap

Sounds like a timing issue to me

Hmm maybe I’ll check the distributor for a third time then maybe I’m just doing it wrong… im setting the harmonic balancer to the 2nd to last mark on the timing cover that’s notated “0” on the compression stroke (noted by air coming out of spark plug hole), putting a punch through the distributor to hold it in place, rotating the oil pump slit to the 11’o clock position, then sliding the distributor in after taking punch out so it rotates into place and points to cylinder 1’s wire? Maybe I should just replace whole distributor if I’m doing it correctly?

Edit: worth noting that if I leave the punch in when placing distributor into the block it always rests decently past cylinder 1’s wire so this second time I took it out to adjust. Guessing my issue might be spawning there
 
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Gotta ask about the elephant in the room. Knocking noise. Bent spark plug. Did You reuse your previous engine plugs ? Is one of your plugs longer than the other? Especially the one in the number three cylinder? Have you got the correct plugs?
 
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Honestly my own fault for rushing into a second engine without doing my due diligence… thinking that after doing a list of tests if I could patch my mistakes by replacing the damaged piston(s) in the current engine with decent condition ones from my old one after running it through with a ball-hone? I know I’ve seen DeXJ do this a lot so curious on opinions…

Ive seen many engines running with good parts from different engines so I don't think that's your problem. Could you have possibly dropped something down the intake ? Which is now smashed into the top of the piston causing interference with the valve and or head ? Did the noise start as soon as the motor started the first time or did it sound normal at first ?
 
Gotta ask about the elephant in the room. Knocking noise. Bent spark plug. Did You reuse your previous engine plugs ? Is one of your plugs longer than the other? Especially the one in the number three cylinder? Have you got the correct plugs?

Waiting for new plugs to come in the mail, got the current plugs out of the old engine prior to it blowing up, they’re a set of Bosch double iridium’s and they were all gapped to around .04 and have about 60k miles on them. When I bent one of them then I threw in a spark plug (a champion plug) from when the engine blew up that looked to be in a good condition. They’re all the same size and fit in my old engine correctly I’m assuming?
 
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Ive seen many engines running with good parts from different engines so I don't think that's your problem. Could you have possibly dropped something down the intake ? Which is now smashed into the top of the piston causing interference with the valve and or head ? Did the noise start as soon as the motor started the first time or did it sound normal at first ?

This is possible, but I had the intake living on a shelf in my friends garage. I have a borescope coming on Sunday to check fully. When I inspected it after taking it out, it did seem somewhat dirty with soot inside.
 
Hmm maybe I’ll check the distributor for a third time then maybe I’m just doing it wrong… im setting the harmonic balancer to the 2nd to last mark on the timing cover that’s notated “0” on the compression stroke (noted by air coming out of spark plug hole), putting a punch through the distributor to hold it in place, rotating the oil pump slit to the 11’o clock position, then sliding the distributor in after taking punch out so it rotates into place and points to cylinder 1’s wire? Maybe I should just replace whole distributor if I’m doing it correctly?

Edit: worth noting that if I leave the punch in when placing distributor into the block it always rests decently past cylinder 1’s wire so this second time I took it out to adjust. Guessing my issue might be spawning there

The skipping sound when it’s cranking could be something on top of the piston.the camera will do you good to see if there is something stuck in there smashing up the plug.
 
The skipping sound when it’s cranking could be something on top of the piston.the camera will do you good to see if there is something stuck in there smashing up the plug.

The borescope came early today and I was able to look around within the cylinders. All the cylinders looked good with only what looked like fuel and carbon reside but cylinder 2 had some small shiny stones inside of it near the valves and on the piston? They looked too reflective to be a normal rock and look to be stuck onto the head?

I also replaced all the plugs with new ones and retimed the engine. upon running the engine they didn’t get smashed, drenched, or dirty like last time but still smelled of fuel when taken out and inspected. What is concerning is that white smoke was present after running the engine for a minute or two but the ticking seemed to slow down as the engine ran longer.

The engine was throwing a P0340 code after starting up w a solid CEL but I wrote this off as me forgetting to plug the cam position sensor back in on the previous attempt to start the motor.

Link to engine running this time:

Link to borescope videos (2nd video is upside down pointing towards the valves):


 
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Ive seen many engines running with good parts from different engines so I don't think that's your problem. Could you have possibly dropped something down the intake ? Which is now smashed into the top of the piston causing interference with the valve and or head ? Did the noise start as soon as the motor started the first time or did it sound normal at first ?

Also worth noting that the noise was present as soon as the motor started!

Edit: Wondering if I should let it run to operating temperature to see if it’s just the cold causing the knock? (Of course if the shiny bits in cylinder 2 don’t look alarming)
 
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Is oil coming out of all your pushrod holes when running? Are any of the rockers loose?

Not sure about the oil coming out of the pushrod holes I can check that soon, but I know that none of the rockers are loose for certain (checked before putting engine in). Can check on Wednesday when I have more time to work on it :)
 
If it’s not missing, and has good oil pressure,I might just sea foam it and drive it for a while it is just a 4.0 after all (lol)

Gauge gives good oil pressure at idle when it was running, was thinking about sea foam and MMO and see if it’s just a gummed up lifter
 
I applaud that you took the flat-bed photo and then made it your avatar.

Yup, didn’t get the chance to take any cool photos on the trail under my ownership before she broke down so figured this was funny enough to be my picture 😅. My girlfriend was with me when it broke down on the 17 and was taking pictures like crazy so figured it would suffice.

IMG_0570.jpeg
 
Gauge gives good oil pressure at idle when it was running, was thinking about sea foam and MMO and see if it’s just a gummed up lifter

I've had a random tick on start up that sounded more like a knock like you have. It simply goes away by shutting the rig off and then starting it up again (oil pressure solves it).

Since your noise is persistent and you've ruled out other possibilities, I would probably pull the head and give the lifters a look.

I understand that MMO could remove varnish to open up the port. I'm a fan of the stuff, but going that route risks more damage by running the engine in this condition.
 
Yup, didn’t get the chance to take any cool photos on the trail under my ownership before she broke down so figured this was funny enough to be my picture 😅. My girlfriend was with me when it broke down on the 17 and was taking pictures like crazy so figured it would suffice.

View attachment 579557

I think it's fantastic and would vote it for ROTM.
 
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I've had a random tick on start up that sounded more like a knock like you have. It simply goes away by shutting the rig off and then starting it up again (oil pressure solves it).

Since your noise is persistent and you've ruled out other possibilities, I would probably pull the head and give the lifters a look.

I understand that MMO could remove varnish to open up the port. I'm a fan of the stuff, but going that route risks more damage by running the engine in this condition.

Ya guess I’m cut out for my work and gonna pull the head this Wednesday… Thinking I should order a new head gasket and lifters while I’m in there just to get it all done in a day or two? Should I also invest money in push rods, valve springs and rockers?
 
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Ya guess I’m cut out for my work and gonna pull the head this Wednesday… Thinking I should order a new head gasket and lifters while I’m in there just to get it all done in a day or two? Should I also invest money in push arms, valve springs and rocker?

I would get a head gasket along with lifters and pushrods in case there are multiple bad lifters. I don't know if anything else should be purchased, but there are knowledgable engine guys in here who could speak on that better than me.

IIRC, I bought multiple Melling valve lifters and pushrods on RockAuto, even though I hoped to only change one lifter. Since I had no plans to replace the camshaft, I didn't want to increase the chance of CS lobe issues by changing more lifters than was needed.

I was able to skip the job since the issue was minor and didn't happen too often. I haven't had the issue happen nearly as often since changing the oil pump and installing a tight fitting pickup tube while doing the RMS. This isn't helpful right now but might be worth keeping in your back pocket for later.
 
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Novak Conversions Jeep Wrangler TJ engine mounts