Think my 4.7 Engine Grenaded!!!

multmigs · 07-02-2012, 09:54 AM

Guys I need some help deciding what to do next. Last week driving home my engine made some horrible noise which I originally thought was me driving over something, i quickly realized as I saw the CEL come on that wasn't the case and coasted to a stop from about 60mph... tried to restart once and heard really bad noises and engine would not catch despite turning over. Parked it and had towed home. Today I removed plugs and valve covers, nothing clearly broken however when I go to turn engine over by hand it rotates only so far and then stops with a metalic scraping sound from the bottom of oil pan just before the point at which it binds up.

I'm thinking something clearly broke inside and I have 185K miles on this original motor, previous owner did seem to take care of it but i do know that about 6 months ago the radiator was replaced and I'm thinking it probably overheated at least once. So I need advice as far as do I continue to strip motor down in the jeep? Or would it be quicker/smarter to just remove entire thing and plan or rebuild or replacement from the start. I see numerous people who have exploded head parts and just replaced them in the car and continued on, i just wonder if thats really possible here and I don't want to waste my time. I guess i need to drain oil next and see what comes out.

Anyone have a good thread on the step by step of how to replace heads in the car i can't seem to find one searching?

**Double E** · 07-02-2012, 10:06 AM

A dropped valve seat is a common issue when an overheat issue occurred. Or perhaps a spun bearing since it sounds like the binding is from the oil pan. I would drop the oil pan & see what's obvious.

If there's nothing obvious I would do a bore scope to look for the obvious.

What does the oil look like when it is drained? If it's siezed, no harm in draining it, right?

Any metal parts come out as well?

multmigs · 07-02-2012, 11:15 AM

Ok pulled all the plugs, #8 is totally exploded as seen and the #7 had the tip smashed down touching the electrode in center? Drained oil no sign of parts in that however its only 2 days old, had maybe 50 miles of drive time and its got a ton of copper dust suspended in it which i assume means a bearing went.

FML?

MoparMan1990 · 07-02-2012, 11:28 AM

Quote:

Originally Posted by multmigs

Ok pulled all the plugs, #8 is totally exploded as seen and the #7 had the tip smashed down touching the electrode in center? Drained oil no sign of parts in that however its only 2 days old, had maybe 50 miles of drive time and its got a ton of copper dust suspended in it which i assume means a bearing went.

FML?

Wow that's crazy I've never seen that before.... Subscribed!

**ZeJokee** · 07-02-2012, 02:21 PM

Great scott those are huge pictures!

**Double E** · 07-02-2012, 02:29 PM

Looks like the valve seat is rolling around in the cylinder.

Grab a magnet-tipped pick up tool & see if you can get it to attach to the tip. (the seats are steel, right?) You might not be able to bring any of it out, but you'll know for certain that there's stuff in there that does not belong.

(I think the piston is aluminum, right?)

If the oil drained with flakes, It would surprise me if the bearing would produce copper flakes. It may be the case, I just thought they were steel/magnesium material.

bbartilson · 07-02-2012, 02:31 PM

Ouch!! And I thought my 4.7 problem was significant.

multmigs · 07-04-2012, 08:47 AM

Have spent some time looking around for replacement long block engine and I need to know which exact engine I have b/c there was 2 versions put into 2003 models apparently and the VIN # does not tell you anything, has to do with the number of notches on the flywheel for the crank sensor? anyone know how i can check that before removing engine from car?

**billzcat1** · 07-04-2012, 03:14 PM

The difference is just between the 4.7L High Output (16 tooth wheel) and the normal 4.7L Powertech (32 tooth wheel). So you don't need to pull the engine to figure out, just look at what kind of engine you have an go from there.

hammerz71 · 07-04-2012, 03:22 PM

I believed you just joined me in the "Dropped Valve Seat Club", we are growing fast!!!

**ratmonkey** · 07-04-2012, 11:11 PM

Four ecu connectors= 32 tooth
Three ecu connectors =16 tooth

Fred007 · 07-05-2012, 05:19 AM

I have a 2000 and a similar problem. Motor still runs, but makes a nasty clanking noise on the rear passenger side. Suspect something bad with one piston, the "dropped valve" seat sounds interesting. We are mostly done pulling the engine and I had a related question but will ask that on a different thread. Bought the Jeep knowing something was wrong with the engine, but it still ran and I can't see anything "major" in the old oil. Figured this would be a good summer project for my son, perhaps my first mistake.

multmigs · 07-05-2012, 07:10 AM

This is looking like the winner to me, for some reason this site has the best price on these, lower than the company website itself by $500..

http://www.drivewire.com/search/?N=0...ND(universal:0)
?
Anyone have any experience using Marshall engines

multmigs · 07-13-2012, 12:15 PM

Just removed engine today and oilpan..... engine noise equals this...

**ZeJokee** · 07-13-2012, 12:17 PM

Im going to have nightmares now. That sucks man.