'90 MM 2.4L FI Build

I say build, but it's more of a cry for help.

I know just enough about mechanics to be dangerous. I can take things apart, and put them back together reasonably enough. But, diagnostics and internals of engines are my downfall.

I've actually never torn an engine down to the pistons/rings area. I've changed many head gaskets (well, 3 to be exact). I've never torn into a head to mess with valves/guides/springs either. Basically, I guess I'm a glorified parts changer. I actually changed the head gasket on this and had it running not great but running. Started and idled perfectly, but would spit and sputter under load, and didn't have much power. Took it to the stealership, and they told me it failed the leak down test. So off with the head again. This time I pulled the engine, cause I was told it could be bad rings by the stealership.

Sooo. that's where I am at, at the moment. Engine out on a stand, head and everyAttachment 8928Attachment 8929Attachment 8930Attachment 8931Attachment 8932Attachment 8933Attachment 8934Attachment 8935Attachment 8936Attachment 8937Attachment 8938Attachment 8939Attachment 8940Attachment 8941Attachment 8942thing else removed. And I don't have a clue where to go next. Well, I do, but, lack of funds has put a stop to things right now. The head seems to need work, and looking at the pistons and cylinder walls, I don't know if I really need to mess with them or not.

So if anyone can make sense of these pictures what do y'all think.

Hi Mitchi - we have the same year and engine, so I hope to be of some help.

I doubt you need rings. Cross-hatching is obvious on the cylinder walls. Next post, please mention the mileage on the engine/truck.

I noticed with #2 or # 3 on the cylinder head the carbon deposit that was prominent on mine, too. Turns out is was the passageway for the EGR valve, and it was completely packed with carbon. It runs through the cylindr head, and also through the plenum (air intake manifold) and the intake manifold as well.

The gutlessness was likely in the various timing things, but since you have it torn down, give it all a good cleaning. Take the EGR off the plenum and clean out that carbon, too. Clean out the EGR valve, itself, and once clean, give it (the moving valve stem) a drop of oil. Give the device some mouth vacuum and see if it works properly.

It's best to wait for other members to chime in, but likely several small problems have added up to one disappointment. That seems to be the way of these trucks, particularly when they're new to us. Many times, the previous owner drove the last few thousand miles with no service or care.

I have a build thread, it might have some insights you can use, it's called "Roy's Garage" and it will help you with some photos and pointers. There's a lot of non-mechanical stuff, so you'll likely have to scroll through a lot of it to get where you want to go.

This forum is a great life-line for just the kind of thing you're doing. Keep us posted on your findings and actions, and asking questions doesn't mean you're dumb: that simply means you need to know. Many here can help. I hope to be one of them.

Man royster, thanks.................mileage I'll check and post when I get home from work tonight

I was figuring on the cylinders looking ok. So pulling the oil pan was a little premature too i guess. Lesson learned.

I did do the test on the head, taking the cam out and having all the valves closed, and turned up. Filled the cavities with brake clean first and within a few hours all the cavities were empty, someone, I think my brother told me that was too thin of liquid, so I used 5w motor oil and that took several days and the #1 cavity was the one that leaked out.

So I'm guessing I may have some valve issues, but, the stealership told me it was #2 cylinder that failed the leak down test, and I did have to pull #2 plug and clean it on occasion, to get it to run a very minute little bit better.

Thanks for the advise, and I will pull that plenun out tonight and start cleaning it and the EGR valve.

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If #1 is leaking, you might do well to remove the valves and see if one is warped. They're dirt cheap to replace, though I don't recommend replacing all of them. Increasing the compression with a tighter head will put pressure on the old block components...so don't do a valve job, per se, just replace any valves that are warperd or bent.

Valve spring compressors are $20 at any auto parts store.

Once you have the valve springs off, see if you can spin the valves in their guides. Probably not, but they're supposed to spin freely during normal use. A little cleaning gets them so thay'll spin, and you can watch closely to see if th edge appears to go up and down as you spin.

Replacing the valve seals is a must, since you've gone this far, and from experience I'll tell you: do that on the bench while the head's out. Doing it with the head bolted to the engine is cumbersome.

Clean out that whole EGR passage, through the head and manifolds. I used Seafoam spray, and let it set overnight. I used some wire to plunge the passageways, sprayed them with brake cleaner to really douche them out.

Spend a couple bucks more and get the good head casket set: it will have additional gaskets and seal you will appreciate. Save the ones you don't use, like the water pump gasket and the silent shaft seal@ the oil pump.

Out of necessity, I kept the hydrolic lifters in place with mechanic's gloves fingers when re-installing the rockerarm assembly: it kept them from falling out and dropping down the oil passages. I highly recommend stuffing rags or otherwise blocking the oil passages while working on the head, to prevent bolts and stuff from accidentally dropping down. http://www.mightyram50.net/vbulletin...ll=1#post26624

And BradMPH recommends re-torquing the head bolts after 300-500 miles. I did this, and it allows you to also check on all the other components/bolts for good repair. Brad says the re-toques assures no blown head gaskets later on. I went with that suggestion.

Likely you had to remove throttle sensors to get the valve cover off. I am in the process of learning how to callibrate these...not sure at all, but i did move the throttle position sensor and the check-engine light isn't coming on much at all, anymore. (Lucky guess in positioning). And also, it's important to know to use the connector on the fender to set the timing.

The details for this engine i flailed around with, and got answers one way or another. I'll never stop thanking Komeuppance for his help, and a few others who lent an experienced cyber-hand to me.

I pass that along to you, Mitchi. :)

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Quote:

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Originally Posted by royster

If #1 is leaking, you might do well to remove the valves and see if one is warped. They're dirt cheap to replace, though I don't recommend replacing all of them. Increasing the compression with a tighter head will put pressure on the old block components...so don't do a valve job, per se, just replace any valves that are warperd or bent.

Valve spring compressors are $20 at any auto parts store.

Once you have the valve springs off, see if you can spin the valves in their guides. Probably not, but they're supposed to spin freely during normal use. A little cleaning gets them so thay'll spin, and you can watch closely to see if th edge appears to go up and down as you spin.

Replacing the valve seals is a must, since you've gone this far, and from experience I'll tell you: do that on the bench while the head's out. Doing it with the head bolted to the engine is cumbersome.

Clean out that whole EGR passage, through the head and manifolds. I used Seafoam spray, and let it set overnight. I used some wire to plunge the passageways, sprayed them with brake cleaner to really douche them out.

Spend a couple bucks more and get the good head casket set: it will have additional gaskets and seal you will appreciate. Save the ones you don't use, like the water pump gasket and the silent shaft seal@ the oil pump.

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Kewl, thanks again....will do. I was thinking of taking the head to a shop.

The extra bucks gasket you speak of, got any recommendations? The one's I was going to buy will cost me 90 bux at a local parts store?

And the valve seals, any particular ones?

Thanks

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Originally Posted by mitchi

Man royster, thanks.................mileage I'll check and post when I get home from work tonight

I was figuring on the cylinders looking ok. So pulling the oil pan was a little premature too i guess. Lesson learned.

I did do the test on the head, taking the cam out and having all the valves closed, and turned up. Filled the cavities with brake clean first and within a few hours all the cavities were empty, someone, I think my brother told me that was too thin of liquid, so I used 5w motor oil and that took several days and the #1 cavity was the one that leaked out.

So I'm guessing I may have some valve issues, but, the stealership told me it was #2 cylinder that failed the leak down test, and I did have to pull #2 plug and clean it on occasion, to get it to run a very minute little bit better.

Thanks for the advise, and I will pull that plenun out tonight and start cleaning it and the EGR valve.

Attachment 8943 Attachment 8944

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Nuttin wrong with using thin fluid to do a check. Water is used and I think some even used fuel. If it takes several days to leak through I wouldn't freak out on it. The oil is a little thick for testing IMO.
I would suggest a valve guide seal replacement if you want something to do and dig into it. You'll need a spring compressor and get a valve grinder tool and some lapping stuff and the correct seals, and have some fun. You can check then if a valve is bent by the wear on the stems and the entire job is actually very easy to do.

Leak down testing the pistons will pretty much test your oil ring seals though the ole compression test is the way to test compression rings and tells the story on the rating of each cylinder. This will help you to start your search on what place to look first.

Nasty EGR valves get carbonized so bad with soot and un burnt fuel residue. You probably need a coat hanger or like a rifle barrel cleaner rod tool with the wire brush tips to clean the tube through the head. Depending on last time cleaned I'm sure you will get a pretty significant amount of black garbage.

Check your cylinder walls for wobble scuffing. IN the photos It looks like I see some or it's the photo. Sometimes older engine will start to wobble the pistons a bit because of worn wrist pins. Though your head looks pretty decent and all look close to the same. Piston top edges look decent also, nothing too terribly different from others I have senn.

Quote:

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Originally Posted by BradMph

Nuttin wrong with using thin fluid to do a check. Water is used and I think some even used fuel. If it takes several days to leak through I wouldn't freak out on it. The oil is a little thick for testing IMO.
I would suggest a valve guide seal replacement if you want something to do and dig into it. You'll need a spring compressor and get a valve grinder tool and some lapping stuff and the correct seals, and have some fun. You can check then if a valve is bent by the wear on the stems and the entire job is actually very easy to do.

Leak down testing the pistons will pretty much test your oil ring seals though the ole compression test is the way to test compression rings and tells the story on the rating of each cylinder. This will help you to start your search on what place to look first.

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Thank for the comments Brad........I actually did a compression check b4 the stealership visit,, and got:

#1 = 150, 150, #2 = 150, 150, #3 = 150, 150, #4 = 160, 162.

7 revolutions each.

Tested twice.

Quote:

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[The extra bucks gasket you speak of, got any recommendations? The one's I was going to buy will cost me 90 bux at a local parts store?

And the valve seals, any particular ones?

Thanks

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That's about the right price range. It should actually come with a set of valve seals. The ones I got were two different seals: one kind for intake, and another for exhaust. I found that the ones for intake (rubber) still allowed leaking, so I got another set (plastic). An additional $20 but worth the piece of mind, and also I haven't had smoke on start-up since.

I don't think you need to send the head out for anything. I'm prone to tell you just reassemble a really clean engine and get what miles are left on it.

Quote:

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Nasty EGR valves get carbonized so bad with soot and un burnt fuel residue. You probably need a coat hanger or like a rifle barrel cleaner rod tool with the wire brush tips to clean the tube through the head. Depending on last time cleaned I'm sure you will get a pretty significant amount of black garbage.

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The EGR passage ends underneith the exhaust valve, so when you take the valve out you'll see what Brad's talking about, there too.

I used a length of 14-gauge house wire so there was some flex. Amazing how much gunkus-funkus is crammed in there.

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^^^^^^^that is sooooo funny^^^^^^^^

juise guys is soooooo funny.........................

I like it here...................life is good..!!

I took pictures of the head with the cam out, and of the hole i think y'alls are talking about for the EGR valve.

Man is that hole plugged. When I get to work tomorrow I'll post pics.

Oh sh1t , wait........spose to go to the "Drive, Chip and Putt Championship" tomorrow at the Augusta National course.

So Monday.

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Originally Posted by mitchi

Oh sh1t , wait........spose to go to the "Drive, Chip and Putt Championship" tomorrow at the Augusta National course.

So Monday.

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Hey! Maybe I'll see you there in Augusta! There's going to be a donutologist convention! "Filled, Glazed and Iced Donutocity Enhancement". Our chairman, Chris P. Kreem, will be giving a lecture about avoiding Dunkatosis by using the proper muscles in the wrist.

Oh, wait: that's Augusta, Virginia.

Boy, it'd be embarrassing to confuse the two events.

Attachment 8952

Darn, wrong illustration: that's the donut universe, not the chocolate iced.

:lmao:^^^^^^^^^^^^^:clappingorange::wavegreen:

Never heard of Augusta, Va. I was stationed at Ft. Lee, Va, lived in Hopewell, Va. Went to Winchester a coupla times for the "Black Powder Turkey Shoot" back in the early 70's.

Originally from Delaware, went to Va Beach every year. Even remember, my dad drove us down to drive thru the bay bridge tunnel when we were kids, back when it was just a 2 laner. Md to late 60's.

Augusta tell ya dis story, when i wuz January concerned about tings wit my wife, I October, "July to me when you went April bout my March Of Honor? December when tings wuz better?" June she wuz cryin' and confessed she DID February, but only so's I May October duh place, June know?

I would take the head to a machine shop and have them check it out and magnaflux it to check for any cracks they will also clean it

RNMM makes a good point, there. Perhaps look into resurfacing, though if there was no problem with head gasket leaks, it might be more than necessary. I've heard the resurfacing isn't expensive, but can also be done on the shop bench, using a sheet of sturdy glass and some sand paper.

When you get the valves off you can check to see if any of the valve guides have slipped down...I had two do that, and did have to send the head to a shop. Guy did a great repair.

And remember: no garage or shop should be without fresh, delicious donuts. Donuts: they're what's for dinner.

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Originally Posted by royster

RNMM makes a good point, there. Perhaps look into resurfacing, though if there was no problem with head gasket leaks, it might be more than necessary. I've heard the resurfacing isn't expensive, but can also be done on the shop bench, using a sheet of sturdy glass and some sand paper.
When you get the valves off you can check to see if any of the valve guides have slipped down...I had two do that, and did have to send the head to a shop. Guy did a great repair.

And remember: no garage or shop should be without fresh, delicious donuts. Donuts: they're what's for dinner.

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I'm right there with you on the donuts, grew up living behind a Dunkin Donuts.....beings the rebel little kid used to go there in all hours of the night.

Here's the head, that hole in the 3rd one looks blocked for sure.

just thought I'd show my daily driver when it's raining::

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The work looks terrific, nice clean up on the valve cover. Glad to see the rockerarm condoms are of use to you.

The Coors can next to the car keys is a bit omenous: watch out for that. The laws for DWI get stricter every year.

Your intake (not of beer, but manifold) is very different from my 4G64, as it appears to be four individual pieces. But the rest is quite familiar. It also seems your EGR goes into cylinder #2, whereas mine is in #3. But there is no question a good part of Jimmy Hoffa is wedged in there...not that Jimmy Hoffa HAD any good parts, I'm jus' sayin'. I have to suppose there were, after all, some differences in the Dodge and Mitsubishi models.

All loking good, Mitchi, and thanks for taking the time to post pictures.

And remember: powdered donuts help kill fleas. Yes, that's right: if that powdered sugar just stays on the dormant donut, it benefits no one. But, when you consume the donuts, powder falls and the tiny particulate gets into exoskeleton joints, just like diatomaceous earth or baby powder, slowly destroying pesky fleas and ants alike. AND it doesn't harm the environment.

Powdered donuts: better than drinking Black Flag.

Oh look your rocker assembly is wearing little condoms. :lmao: (now it's safe from Mr.Donuts):rolling:

ooops....yeah, those intakes are from my other SOHC ride. Couldn't get that picture out. Oh, yeah, drinking and driving is not a thing I do,

So, no worries there. Will be working on this head though out the week. You royster and others have reinvigorated me I'm wanting to get this thing back in, It just seemed to me this thing was a lost cause, but y'alls have restored my faith.

Thanks guys.

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Originally Posted by BradMph

Oh look your rocker assembly is wearing little condoms.

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Didn't you notice the vault in the background? They're preparing for safe sex.

And just for the donut unsult, NO SOUP FOR YOU!

I thought that the conditions under which my engine still ran were bad, but RamBam's takes the cake (or donut). So I've seen that these engines are very hearty, and given proper attention, they can go on forever [cue Seline Dion...no, wait: please DON'T cue Seline Dion.]

nice clean-up