I was also thinking that when the balance shaft belt/timing belt failed, the valves might have caused those indentations in the piston??
I was also thinking that when the balance shaft belt/timing belt failed, the valves might have caused those indentations in the piston??
Ouch. Here's what we need to know: did the main timing belt strip or break, and if so, at what speed was the engine...i.e. idling, highway? It may explain this valve (#1 cylinder?) not fully seated, indicating it's bentI am currently replacing the timing belt and the *infamous* silent shaft belt, both of which failed a couple days ago
image.jpg
At 100,000 miles, if the belts were never changed, it's no wonder they surrendered up the ghost.
I'm prone to go with the analysis regarding the little pock marks....that some little piece o'crap got in there and hammered around until it was disintegrated or pooped out the exhaust valve. I wouldn't be concerned greatly as long as there are no score marks on the cylinder wall.
Are you concerned about a crack in the head? The photos don't really let us see it closely. Sometimes the original mould process, (when the aluminum was poured molten into the cast), it will make patterns that look like cracks, but aren't. This requires some close scrutiny.
Keep asking questions: we'll get you there, kiddo!
The greatest gift you have to give to the world is that of your own self~transformation.
The problem is you don't know what level of abuse the engine took from its PO. When I did an autopsy on my 4G63 it had seized, twisted the crank on #1 big end and then managed to free itself. End result was the PO 'thought' it was o.k. but was only timed on #1 cylinder - all the others were now miss-timed. I would personally take #3 piston out and have a look at the crown of it. You'll know straight up if it was overheated. Plus there will be signs of scoring on the side of the piston bore supporting that observation. If it's only mechanical damage you can give the piston top a light tidy up as those chips and dents will potentially aid pre-ignition which will mess with how that cylinder runs.Originally Posted by cjb2679n
Geezer, what does that mean for me?
i'd also like to note that it never got close to overheating when I drove it...
cjb2679n
Could you post a straight on pic of #2 & 3 pistons at TDC ?... (roll crank till both come up),
Unless I am really missing something here, #3 piston DOES NOT look to be the same as 1,2,&4 !?!
Thx,
I have a theory on the damage to the quench area of the head, but need the pic to confirm.
Thx again.
I'm looking at it too but it's hard to tell if they're different. The other piston tops are pretty fouled up but the quench area on #3 looks thicker/bigger or something. If someone swapped a piston and the landing above the top ring was thicker, I thought the engine would've locked up...
Agreed,
& same was My hypothesis, someone swapped a single piston into #3 at some point, hence the pic update request.
The exh valve on #3 does not show any evidence of piston contact...(from the one head pic )
& the combustion chamber proper (if You will) shows no signs of broken component 'rattle' contact !
Lets stand by for the updated piston(s) pic.
A pleasure as always geezer !!!
OK. I took some better photos. As shown, pistons 2 and 3 at TDC (notice how #3 has waaaay less carbon deposits on it) You can also And then there's the photo of the tiny crack in the valve bowl on #4, running from the spark plug hole to (possibly?) the exhaust valve, it's hard to tell if it goes all the way without removing the valve. Next is a picture of the #3 cylinder wall which has some scoring marks, including one that I can feel with my finger. There's a pic of the coolant beads on #3 cylinder wall. Not sure if this is only because intake manifold gasket was bad? And then, to improve morale, I pilfered this mitsubishi logo from the auto salvage place where i went to scout replacement cylinder heads in case this thing goes south. Thanks again guys, I couldn't have gotten this far without your input.
Last edited by cjb2679n; 02-07-2016 at 02:52 PM.
Also, Royster, in response to your post, the balance shaft belt broke and the timing belt stripped, but it was intact when I removed it. This occured at probably 30 mph and as soon as I heard the noise I braked and stopped the engine...
As Sir Claych has pointed out, there is no indication of valve/piston conflict. But this motor definitely has some issues.
I'm very trusting of what geezer and sir claych have to say, and I'm going to remain secondary on this. I was able to enlarge the head-crack photo considerably, and while it looks like a crack, a final test might be in order before finding a junk yard replacement. My suggestion would be to place one drop of dye in the middle, and see how it spreads. I'm confident geez has a better test, so wait and see what he says.
Since the 4G64 IS an inteferance engine, there is likely to be at least SOME valve bending, you can check on that when you remove valves...if you end up doing that. If it turns out to indeed be a head crack, the next step is to see if it can be welded.
I'll be cheerin' for ya, cjb!
The greatest gift you have to give to the world is that of your own self~transformation.
I also remain curious as to why the belt stripped...are you running thick oil in it? Also, what condition are the cam shaft journals in? No scoring?
Just my morbid curiosity: this scenarios, of course, is what caused my belt to strip (thick-ass oil)...hence I learned the whole process!
The greatest gift you have to give to the world is that of your own self~transformation.
That's what belts normally do. Once a tooth or 2 peel from the inner face of the belt from fatigue, it loses grip on the sprockets and then tears a few more off just to make sure. I've never seen a belt actually 'snap'.
Gee, thanks Roy. No pressure...Nup, I got nada. I'd take it to a shop and get it pressure tested. I would be worried that any test I'd do at home wouldn't be conclusive and I'd end up being forced to pull the whole thing apart.
you can buy the dye test kits online, but a pressure test is the best way to be sure the head is good.
Pennyman1
The best Dodge that Dodge never made
Living the D-50 lifestyle since 1980
There ya have it.
Meanwhile, how about some pictures of the rest of the truck, cjb??
The greatest gift you have to give to the world is that of your own self~transformation.
Clean piston top = water/coolant entry. You got a crack...or a dud head gasket. Seeming you can see a crack, well there's the culprit
Really freak the guys out and find a Triton emblem for it too. That'll get them guessing
Royster, I'll post some pics soon when I can get all the stuff out of the bed and all the parts out of the cab and get her cleaned up a little bit...she'd be real mad if I took a picture in this state. Did I mention I live in an apartment? All this work has been done curbside, and I have to pile everything into the cab each time I finish working for the dayOh, for a garage...
Clean piston top = water/coolant entry. You got a crack...or a dud head gasket. Seeming you can see a crack, well there's the culprit
Geezer, one thing confuses me-- the little crack is in the valve bowl on cylinder #4, and the coolant was found in cylinder #3.... It makes me thing it was a bad head gasket/seal and that this little crack, while it probably needs to be repaired, wasn't really the source of my problems...I'm gonna take it to a head shoptomorrow and have them run a pressure test. I hope it works out, because for what I paid for this truck i can't really justify spending more than a couple hundred bucks to get it running again
Last edited by cjb2679n; 02-08-2016 at 03:16 PM.
That one has me baffled, too.the little crack is in the valve bowl on cylinder #4, and the coolant was found in cylinder #3
The greatest gift you have to give to the world is that of your own self~transformation.
Yeah, I didn't read that correctly - my bad. As for having to spend to get it running again, it will be worth it once it's done right. Unfortunately these things happen and something always breaks or wears out. Hope you get good news from the head shop. Worse case scenario of getting a decent used head won't be that bad.
cjb2679n.
Good deal on #3 piston !!, my hypothesis was wrong which = less out of pocket for You !!
So, onto the crack in # 4. Called a friend of mine whom owns a very reputable local
machine shop, (& is one of The best Cyl Head Specialists I have ever seen),
Described the crack & location, linked the pic, ...
His thoughts,
1) I do not see any evidence of coolant entry,
2) As such the determining factor will be how far(if at all)
the crack runs under the valve seat insert & down the
threads in the plug bore.
3) I have seen dozens of these type of cracks & unless
You are going to run 20# of boost you may not need to
address the issue at all.
4) but then cracks do not shrink.
So, Obviously a proper clean & pressure ck (as already advised) is in order...
However that crack may be a non- issue for a stock 'used as a truck' repair.
As to how the cracks form, casting shift from forms, & alloy variables.
Fingers crossed for Ya !!!
Update:
After taking the head to a (very reputable) machine shop, the verdict was that the head was too badly warped to be repaired. It had apparently been rebuilt once before. So. I'm in the market for a decent used cylinder head if anyone has one! I'm checking around at the salvage yards here but nothing yet :/
Also shout out to clay for doing some research for me!
Last edited by cjb2679n; 02-11-2016 at 06:36 PM.
Well that explains your coolant leak.
We'll all hope for a good head to come your way.
The greatest gift you have to give to the world is that of your own self~transformation.
Dumb question maybe, but the head for the 2.0L wouldn't work for my 2.4L would it?
Not a dumb question at all.
It will fit, but I'm not sure it will work. Plus you'd need a plate to cover the fuel pump hole on the 2.0.
The greatest gift you have to give to the world is that of your own self~transformation.
Far as I can tell, worse thing that could happen is a bump in compression. Only real difference between the 2.0 and 2.4 is the extra 6mm deck height on the 2.4 block. Oh, and the fuel pump block off plate you'll need as Royster has pointed out. Only thing that may cause grief are head mounting bolts (there are different diameter bolts with changes from 6 to 7 bolt blocks but when exactly I'm not sure and I don't know if it's applicable to this swap). If they use the same design/diameter you'll be good to go. Put the icing on the cake and port it while you're at it
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