Roy's Garage: '90 2.4-4G64 5-spd D-50

[royster]

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This is my "build thread". I will share all my experience gathered about the 2.4 4G64 so others can have the information. We can all learn from other's experiences.

QUICK REFERENCE MENU:

'89-'90 2.0 and 2.4 cross-breeding has information about what we CAN't do with the two different engines, and what those differences are. (Thanks to contributors)

Why Didn't I Think Of That? Hints, tricks and products you'll find helpful

Hello From Virginia is where I introduce myself to the forum.

4G64-2.4 Photographic Engine Reference How the 4G64 should look, highlights of important points (like timing marks, connector location and silent shaft accesses)

2.4 OIL PUMP REPLACEMENT - Helpful to those with the 2.0 as well, step-by-step with photos

TIMING BELT REPLACEMENT - may be of some help where the service manuals lack

SETTING THE IGNITION TIMING using the ignition timing connector

CYLINDER HEAD WORK/ VALVE SEALS follows my learning experience...including mistakes in analysing...that you might learn from, too.

Rear Drum Brake Overhaul Pictorial walk-through of my experience.

CLARITY FOR BEGINNERS

These engines have some unique features, and some specific issues. Click the orange title to go to thread posts.

Removing Valve Springs, Valve Seals - I found very little information about these details, so I write about my experience. Photos and references.
Valve Seals information runs through the thread as I gather information about them.

Silent Shaft(s) also called “balance shafts”. Mitsubishi came up with this idea, and while some modifiers like to remove them, they were installed to reduce engine vibration. When starting out to work on my 2.4, I had no idea what a silent shaft was. I learned by researching and doing.

There are two of them in the 2.0 and 2.4 2nd generation motors. One on the left, activated by its own little timing belt (referred to as the “B Belt”), and one on the right, which is gear-driven by the oil pump gear. As balancing devices, their timing placement is important for them to operate correctly.
More About Silent Shafts

Removing The Rocker Arm Assembly on the 2.4 requires careful attention, as the hydraulic lifters inside the rocker arms can…and do…fall out during the assembly removal. They can easily fall down the cylinder head oil passages if you don’t take care to prevent this.

PONY - photo album of my 1990 D-50

My sincerest thanks to BradhMPH, Komeuppance, RedNeckMoparMan and all who participated...for their thoughtful help and kind assistance. I couldn't have succeeded without your inputs.

My intention is to adhere to stock (non-modification) mechanical protocols. As the information was slowly gathered, you will do well to take the time to read through the thread.

I know that this forum was of great help to me BEFORE I joined, and it has been (continues to be) an enormous help since I joined. It is my hope Roy's Garage will help at least one person out there who finds themselves the proud...but uneducated...owner of a similar vehicle.

As a "build thread", the first thing I need to do is build the garage. That's next.

[royster]

The garage was abandoned for many years before I got here. It is a solid building: the framing is all oak, constructed in the 1940's. However, it had a dirt floor and no way to enclose the front. I opted to joist the floor up, instead of pouring concrete...it would have been near to impossible to get a concrete truck in that area.

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A combination of "Great Stuff" expanding foam (also called "Architect's Foam") and concrete padding supports the joists, specifically where I knew weight was going to be distributed. The joists are 14" on-center instead of 16". 3/4" plywood was glued-and-screwed to the joists, with foam insulation strips placed between joists (an ultimate recycling project: the insulation strips were cut-offs from some previous project).

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The walls were firred out with 2x4's, insulated and paneled with 1/2" plywood ("shear paneling"), glued with construction adhesive and screwed with drywall screws (2").

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5 huge 2x8 solid oak rafter beams were originally installed very low, so I removed them and took the rafters up to the wall tops, more than doubling the rafter count, with two 2x8's in the center, where window openings existed, and new windows would go.

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[royster]

The story takes an interesting, life~altering twist at this point.

I had an adopted cat, whose owner had been admitted into a nursing home. When I began the garage project, I fed him out there at the job site. One day I noticed a stray had been eating his food. I befriended her, and it turns out she had 3 kittens, nursing near my house. There were some awesome days of raising the kittens, working on the garage, and enjoying summer. My rescue cat was not amused by the intrusion, but tolerated everything.

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Soon enough, walls were serviceable and the doors ready to install. Click-to-enlarge photo to see the mother cat eating near the blue chair.

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About the time the kittens were weened, some incident or factor caused both adult cats to die on the same day. I was left with three orphaned kittens, who I kept in the garage at night once the doors were in place.

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Work went on, the kittens grew, and one day, I bought a 1990 Dodge D-50: another life~altering event.

[royster]

My workbench is two 3/4" plywood sheets glued-and-screwed together, the top sheet of plywood being oak veneered. 2" heat-fused edge-banding makes the workbench look like a solid piece of oak. Second-hand oak cabinets were found here and there, and soon enough I had the garage I had wanted since my mother kicked the rock band out of hers', 4 decades ago.
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[royster]

Please allow me one more construction post before we park that D-50 in here.

The garage has evolved much since the previous pictures were taken. There is a functioning kitchenette with a stove/refrigerator apartment unit I found at a thrift store many years ago, for $15. Not show in the photo provided are the nice oak overhead cabinets I found and installed. A double stainless steel sink drains outside via a filtration system (I AM, after all, from California: we pioneered environmental awareness), and a rainwater retrieval system is designed (but not working, yet) to provide water for washing hands, gravity-feed with optional pump-assist. The garage has 100 amp service.

The work bench will hold 400 pounds before it will start questioning my motives. Remember, the walls are real 2x4 oak studs, reinforced and sheer paneled. It was when I decided to replace u-joints in the D-50 that the pristine workbench got its first dents and scratches. The Japanese call such marks "Wabi Sabi", meaning they tell a specific story instead of "decreasing the value of" that which is not perfect because it has been used.

Because of the way I framed and paneled the garage, it is essentially one huge speaker, because sound transfers nicely out, the bass is carried through the walls and floor like a giant woofer. I have a stereo system than can be heard all through the hills clearly. It is a very good thing I don't drink anymore. The radio/stereo amplifier is built into the wall. Two speakers are screwed tightly to the walls, and two tower speakers sit on the floor when I don't need the space to work.

The garage serves also as a carpentry workshop. It has a built-in air conditioning unit, and in winter, I heat with a kerosene heater.

The garage, as it looks today, can be seen in the following photos (future posts) of present-day work with D-50's.

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The cats grew up with loving care, and they had each other when I wasn't around. Their natural instincts were not hindered by human demands, so they in fact do go into the creek to hunt for fish. The twins are directly related to Maine Coon cats, who are in turn directly related to African Wildcats. The calico-furred cat is a representitive of every forest animal...including the skunks camoit fights (She waddles just LIKE a skunk!) Assuming they were born in late May, I named the twins "Castor" (the male) and "Pollux" (female), the twins of the constellation Gemini. And "Gemini" is the calico cat, with colors split perfectly down the center of her face.
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[thefreack]

Looks nice. Should be a good space to fix that truck in and many other vehicles I'm sure

[royster]

Thanks. I've done extensive work on the D-50 in here, then the '95 Mercury Sable (ugh) and the F-150 enjoys service there, too. What i appreciate so much is a solid, level floor that I can put the truck on jack stands all around and it's safe. Couldn't do that with a dirt floor, nor use a creeper. (By the way, I made my own creeper. It's a back-pad from an exercize contraption, with 2x2 rails attached and small wheels attached to THAT. I bought the pivoting wheels at Lowe's. It works pretty good).

[royster]

MY D-50 STORY
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What I learned, just up to this point, might help someone else NOT make the same mistakes I (and others) made. Life is like that: we can learn from others, or learn from hard knocks. "Experience is the best teacher", and this is so true. You can read from 100 books, but until you experience in real-time, you don't know much.

Varying degrees of smoke would emerge from the exhaust system when I started up my "new" truck. It didn't happen when the motor was warmed up, only after sitting for periods of time. What I didn't know then was what this was a clear symptom of: worn valve stem seals. There is a fairly easy repair for this problem (a thread HERE discusses it) that gives good results. But I didn't know at the time. I figured loading the motor with the thickest oil I could find would buy me some time. It likely caused the timing belt to strip. I ran pure Lucas Stop-Smoke oil, which is okay at operating temperatures, but gets so thick and "slow" at cold temperatures, it probably can't get through oil filters or passageways. And what I have to share is: thick oil doesn't permanently fix the problem. Replacing the valve stem seals DOES.

What I suspect happened is that the cold temperatures (40-30 degrees F) made turning the cam shaft hard, and at some point this stress caused the timing belt to strip. There might be another bearing issue on the head, and I won't know until I get the valve cover off. I did get the full timing cover off, and the secondary belt is fine. The belts were actually in very good shape when I bought the vehicle. My own "old thinking" (from conventional, American-made motors) essentially killed the D-50...for now.

But the experience pushed me to look into these trucks and engines with full focus...no half-measures...and it ultimately brought me to this forum.

If you're living in a cold climate area and have put thick oil in your D-50 or Mighty Max, take the time to pour a can of SeaFoam into the crank and thin out the oil, pronto. Let it run for a bit, then change the oil. Run pure 30 weight, but don't put STP or oil thickeners in there. Your smoking problem is more likely these seals than it is the rings.

Another valuable tip I learned from the community here is that the hard-starting of my D-50 was likely a bad water-temperature sensor. I wondered why the choke didn't seem to be working, and quite frankly, I wasn't sure if my D-50 had a carborator or was fuel injected. So live and learn. My "conventional" mechanical experience didn't help me to understand the 4G64, other than basics. It's a whole different ball-game than a slant six 225. Vehicles with timing chains can endure the stress: timing belts will only take so much before they file for divorce and demand custody of the glazed-donut locker.

[royster]

I was fortunate that the belt stripped while idling. The truck started after the usual cold complaining ("You left the toilet seat up again!" - "You never take me out, any more..." - "Not tonight, I have the headache From Hell, you self-centered bastard...") and ran for a few moments...maybe 45 seconds once the idle smoothed out. Then a loud "clink"...which, at the time, sounded suspiciously like $2,000.00...and the motor stopped. I tried cranking it, and it made a very different cranking sound. It was likely the sound of the crankshaft gears spinning on the timing belt.

So my "old thinking" was I could locate virtually any old D-50 that sorta looked like mine, and swap parts. After all, it's the same head on a slant 6 - 225 or 170. But asking around this forum, I'm told that the 2.4 and 2.0 ...not to mention the 4G64 and the G63B (respectively) are two different animals. One is wider than the other, so the transmissions, too, won't exchange. Notice your 5-speed trans is a one-piece casing, not a bell housing you can remove and use for an oil funnel or baby bonnet.

Well, I DID locate an '89 D-50, thinking a swap aughta/coulda/should work...and it was by asking the experts here that I understood there's no half-measure, quick-fix approach to serious, enduring repairs to our Little Tin Cans. What I share with you here is to the best of my knowledge, and I certainly hope to get corrected when I post bad information. I also hope that when the information is correct, you'll post a verification. I don't mind learning as I go: I have the time to do so. Others might not be as fortunate, and need to know from the start.

Be sure to review the thread '89-'90 2.0 and 2.4 cross-breeding if you haven't already, and want that information. At present, as I part out the '89, I will learn if the calipers, drums and such are inter-changeable, [EDIT: they are] and share that info with you.

I was very fond of American Motors Hornets and Gremlins, and the whole line of those cars had completely interchangeable parts. I have to learn new skills, today, to satisfactorily work on D-50's. That involves humbly learning from others, as well as my own mistakes.

[royster]

IN OTHER NEWS...

I have an appreciation for all the various modified trucks on this forum. I have chosen to remain faithuflly stock, and am happy to be able to replace little details my own truck was missing when I bought it. Itty-bitty details like a cap on the windsheild wiper bolt. Replacing weathered details like the door handles (exterior) and other appointments that make the truck look closer to showroom condition. I joined the "Stockers" group on this forum for this reason. The truck will be very much a "statement" of my own, just like the extreme modified trucks here, only stock, with after-market upgrades within reason. The parts truck gives me many opportunities, and other members too, to restore lost parts or functions, spiff up that which can be spiffed, and most of all, an appreciative audience to share it with.

[royster]

Lighten UP: this IS a Joke...

As you might be aware, I'm parting out the '89 D-50. Among other still-working equipment items is the windsheild washer reservoir and pump. I've cleaned them up and you might want to get this package for your "in-flight" cocktail service. Secure the reservoir somewhere in the engine compartment and run 1/4" line to the driver's seat, with enough line to put in your mouth. Simply fill the cleverly-concealed reservoir with vodka and orange juice and hit the "wash" lever: screwdrivers in the mouth, without taking both hands off the wheel! Or fill with your favorite OTHER cocktail: zombies, FudPuckers and classic Rum And Coke. [disclaimer: hot coffee is not advised, and beer doesn't work. Be sure to distinguish WHICH line is for sipping, and which line is for windsheild washing...confusing the two could spell disaster if your windsheild gets dirty.]

When you get pulled over for driving through the bank to order cheeseburgers, there will be no empty containers to point an accusing finger at alcohol! It's all under the hood, where cops don't think to look.

I actually heard this story in one of the A.A. meetings. I'm not making this up!

[BradMph]

The police can't arrest you for something like that which could of possibly been placed on the outside of the drivers compartment by another party. Though if they find you been sucking on your windshield washer fluid for the past 20 miles, it may get touchy in court.

[royster]

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This photo was taken only a couple days ago, and shows the parts-truck in dismantle-mode. Presently I'm trying to get the drums off the rear end (they're stubborn) [EDIT: they are removed by placing two 9mm bolts in the threaded holes, and tightened, much like a wheel puller] and work with getting some member-requested parts-yanking done. The head comes off tonight...the REAL deciding factor regarding the engine's status (and what I can sell it for) as well as the front bumper. It's up on 4 jacks (beats a full house) and I'm eager to get it out of the garage so I can get into resurrecting the Tin Can.

Just in front of the truck is the kerosene heater. It's tight quarters, but comfortable. The cats think the parts truck is their personal climber: one likes sleeping on the floorboard, and the other likes sleeping on the roof of the truck.

Just beyond the kerosene heater, you see a "board" attached to the wall. It is a table top, flipped up. When the garage is not a car port, the table top flips down on top of my table saw, and two bar stools sit on either side. Another great crap catcher.

[royster]

Dismantling the 2.0 is teaching me a lot about how to proceed with this type engine. First thing to do after the valve cover comes off: PLUG THE OIL HOLES so small parts don't find their way down there. This didn't happen to me...God is always gentle on that first warning...it's just something I realised when a small part did drop off the valve assembly as I removed it. I also capped the dip stick tube after removing the dip stick (although he was re-elected for a second term).

It's stunning how many &%@#!!! vacuum lines there are on the carborated engine.

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[BradMph]

You have Tree dwellers and bush dwellers for cats. Some like it low and others like it up high. More likely the girls are up higher.

Here are our 2 kids. Flew them out from Ohio to Spokane, WA when kittens about 3 years ago.
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[royster]

Yup: it's the girls, alright.

In other news: this is an important note to remind me (and others) about servicing the head (on your truck ):

There are one time use ARP bolts for heads and if I'm not mistaken, also multiuse also. Like I stated in a past thread...I have used my STOCK head bolts consistently for...well I have never replaced them and the truck is a 1986. If you want to purchase the ARP bolts, go right ahead, but be prepared to buy again the next time you change a head gasket.
Mitsubishi had a problem with head gaskets and crack heads years back when apparently they did not tighten the head bolts correctly on their trucks right out of the factory. This caused warping and head cracking in many vehicles, especially the 2.6L. If you do not want to buy a one time use of the head bolts, it will be just fine. The most important part of head bolt tightening is to retighten after you have ran truck for 300-500 miles and it is warmed up when you do this second round. Follow this procedure and you will almost never blow a head gasket unless you severely overheat the engine and try to make it home on 220 degrees boiling steam. Also don't forget to have the head checked for warping. This should be automatically done at head removals. Also replace the head bolts into their same exact holes they came out of.

Thanks, Brad. Good to have friends around the garage kerosene heater...furry AND flesh.

[royster]

These seat covers were a quick fix when I first got the truck...I crammed a lot of tasks into a week, and never really finished the covers, just wanted things to look good, and clean.

The parts truck gives me an opportunity to do a really good upholstery job, with material I really like, and padding in some areas (the stock seats are not comfortable after 20 minutes). Bucket seats are still an option, but for now, re-upholstering the parts-truck bench seat is something I can play with, after the major surgery to get the '90 back on the road.

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[royster]

I crammed a lot of tasks into a week

I knew nothing about D-50's, and I hadn't gotten into enough trouble yet to set me on the path to find this forum All I knew was that I loved my cool little truck, and it needed some loving cosmetic care: the black paint around the door windows was almost white from deoxidation. Black plastic parts needed some mineral oil. And that cheesy upholstery had to go.

Knowing what I do now, I wish I had taken pictures...there are some, but not of the whole process. The gas tank repair probably would have been useful to some future Rammer, because one thing that's consistant in these trucks: Rust Never Sleeps.

It was a wonderful time detailing the truck, just basics to bring it up to "cared for" condition. But now that I am on this forum, I see the work others have done on their trucks and it's amazing the time and detail spent. I can't try to be "like the Big Boys", and I am fine being just a curb mechanic with a stock truck: the forum has made me feel welcome, that way. I probably represent lots of visitors to this forum, who are not extreme-modifying their trucks, but just keeping the basics intact. "The thing we have most in common...are our differences".

A list of what I did in that first week:
. Took the bumper off and gave it a good paint job after some straightening. Dupli-Color "Universal Black" with some clear coat. Same paint for the rims which I sanded and painted before getting new tires. I tried to locate chrome wheel-center caps but for now settle for painted.
. Painted the grille. Took a Ram emblem off the side, beveled it with a belt sander to fit inside the grille, and mounted it.
. Removed the instrument cluster and completely cleaned it inside and out, all new bulbs. While it was out, installed the tach and and running-lights switch.
. Door panels came off and got mild modification and paint, after-market window cranks replaced cheesy plastic ones.
. Used the Bissel upholstery attachment and "steam cleaned" headliner and carpet while bench seat was out. (Only 6 simple bolts to remove the seat in two pieces make it very easy to work with. Just like my first wife, it was an easy in and out.
. Installed a good music system. It will vibrate nearby buildings sufficiently, but I don't do that (anymore :D ) unless it's Led Zepplin or ZZ Top. It's a simple Dual CD player with a pre-amp. I quit listening to radio long ago. (In 1995 I walked out of the local radio station I worked at, after leaving a note on the wall: "Radio is dead". ClearChannel was buying up all the stations in the country, and what we have today is a pipeline of crap. There is no "career in radio" unless you think reading from a script and playing music from a computer-generated list is artistic).
. Putting the truck up on jacks:
. dropped the drive shaft and transmission. "Preventitive maintenance" of replacing u-joints might have been a mistake: I get some 55MPH vibration.
. Replaced the throw out bearing only to find the one in it was fairly new. This DID allow me to inspect the clutch, and also "get my feet wet" in doing deeper mechanical work...something I had not done for many years (I had no place to do it). Drained and replaced trans and differential oil.
. Dropped the fuel tank and addressed the leaking fuel line issue. It was in trying to locate a fuel pump that I began the realization of how hard it is to get parts for these little guys. I'm thinking this is a common D-50 'losing virginity' moment: you either dedicate yourself to these trucks or get rid of them. I'm keeping mine. After all: it has cup holders.

The truck spent additional time in a repair shop where the front end rubber was all replaced and the wheels aligned. Seems to me they replaced the pitman arm, too. At any rate, that front end is right. New shocks all around.

That sort of brings me up to speed as to this forum: my story is around here in different places, but the short of it is that I have mechanical problems to correct, and in finding the answers, discovered a whole community of Mighty Rammers (oddly, this reminds me of that first wife) and the culture of these unique vehicles. I'm not alone, out in that garage, and I have a place to share this, whereas otherwise, no one gives a rat's patooki.

And today, I hope to get the parts truck out of the garage, and begin my real journey.

All of this has just been a primer for what's to come.

[below: removing the fuel tank]
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replacing u-joints might have been a mistake: I get some 55MPH vibration.

I wish to make it clear that I know about replacing u-joints and the proper proceedure to do so. I need to check the alignment on the transmission mount, and also probably need the drive shaft re-balanced. Regardless that the u-joints are new, there is some visible play in the joins. Ghhhuhkk.

[royster]

It took a couple of hours, but I got the dashboard off the '89, and now can send the heater ducting to the freack. He assures me he's quite ready to spend a day tearing out the dash to put this stuff in there.

God save any of us if we EVER have to replace that heater core. (They look pretty "permanent", though).

I had the idea for shipping reimbursement for those who asked for parts: instead of cash, check or money order, you can just send a Lowe's gift card with the amount rounded as close as possible. I'm happy with that.

Will be shipping Monday, tomorrow the '90 for sure gets into the garage. I'm ready for that journey.

[royster]

'Got the '90 over to the garage today, no small feat. I did it alone. I had to roll it down the driveway (on its own gravitational power) then across the creek, where I had to pull it up an incline with the F-150 make a sharp right-hand pivot, (back and forth, back and forth...in the mud) then towed it 400 feet (20 feet at a time, to adjust the steering) to the garage with my F-150. The last 20 feet I actually towed it with my riding mower That must have been a sight to see: the riding mower pulling forward with no one at the wheel, and me at the caboose-end of all this, pushing the truck. But all I had to do to stop the mower was quit pushing the truck. Might have looked funny, but got the job done.

In carpentry, a helper can often be replaced by a well-placed nail. I adapt this thinking to automotive endeavors, too.

[royster]

Got the valve cover off and did a close inspection. It didn't take long to notice that the forward-most cAm shaft bolts...the two short ones..are missing completely. So far, no sign of them. I also (sigh, whimper) noticed cracks on the cam bearing casing where the bolts are missing. That's as far as I got for today, because I'm a Tired White Boy and tomorrow is another day.

BTW, these head bolts are the 10MM allen-wrench type, also. And an interesting thing I noticed was the cam lobe is there for a fuel pump, though of course nothing is hooked up to it.

Any chance I can get away with moving the whole f.i. intake manifold off to the side in one piece, or do I have to really get into breaking this down? (The maniforld is a two-piece component).

[royster]

Any chance I can get away with moving the whole f.i. intake manifold off to the side in one piece, or do I have to really get into breaking this down? (The maniforld is a two-piece component).

No, you lazy bastard! You wanted a project vehicle, and now you GOT one! "Half-measures availed us nothing", remember!? 'Book tells ya how... ain't nuthin' TO it but to DO it.

In other news, today:
. Seafoamed the F-150. The Shenandaoh Valley did not blow up.
. Got parts mailed to the freack and Ram5--Newb.
. Cleaned up flood damage, put foot bridge back across the creek.

Now the D-50 update:

Uh-oh: metal shavings in the drained oil. Not a lot of 'em, but still: no one likes finding hair in their food.

I got the rocker arm assembly off, and the center bearing has some serious scoring. Looking at the rocker arms, themselves, #1 ans 2 intake have some serious pitting. #3 exhaust likewise. Everything else looks good. I remembered (at the last minute) to block the oil drain holes before lifting up the assembly.

Patiently working on getting lines/hoses labled, and the fuel injector body off, then the manifolds. I don't expect to have the cylinder head off tonight, but tomorrow for sure. Then I'll know 75% of the story.

[royster]

"Plenum" I think the book calls it.

Well, I DID get the head off and didn't see any evidence of the valves striking the pistons. Since I'll have the head on the bench to replace valve seals, I can test each one to see if they're bent.

Ship-loads of carbon in that head, and lots of oil everywhere, including the intake manifold. #3 cylinder is pretty glazed, but there is still cross-hatching on all the others.

Am I to understand there are two silent shafts? AND...is there an easy way to test the oil pump while stripped down like this?

[royster]

Today's chores were primatily cleaning up, cleaning parts, and doing some close scrutiny. For those who are as clueless as I am on 2.0 and 2.4 liter engines, I'll share what I learned first-hand today.

The heads are nearly identical, except I'm comparing an '89 carborated to a '90 fuel injected. Some interesting facts made themselves obvious.

. While the cam shafts are nearly identical, and could interchange (I would not trust this to work) it's interesting to note the cam lobes are narrower on the 2.4, which has rollers instead of direct rocker arm contact with the cam. A subtle difference is also just behind the cam gear, and it is a "fan" pattern which is more pronounced on the 2.4. I believe it has to do with oil distribution. Lobe-positioning is the same.

. The head gaskets are the same. I measured both heads, and they are the same dimensions.

. As of yet, it appears the cam bearings and rocker arm placement is identical. I do NOT recommend trying to use one cam in the other engine.

. The intake valves are 1/8" larger on the 2.4. Hoping to maybe switch two valves I measured as the first step to that possibility. It won't work.

. The cam gear that the timing belt drives is narrower on the 2.0.

In short, my entire experience tells me I cannot use parts from the 2.0 for my 2.4. Except possibly...and I'll report later...the bolt-down bearings for the cam.
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After the 2.4 cylinder head was cleaned up, I tested the valve seal against the seat by spraying JB Blaster (Liquid Wrench) into the exhaust ports, enough to puddle around the valve seats. The exhaust valve against the cylinder head showed absolutely no leakage.

When this test was done on the intake valves, #1 and #3 leaked. (#2 and 4 didn't). This told me these were likely the valves that had unfriendly contact with the pistons when the timing belt slipped. Close scrutiny showed a very subtle but definitive contact mark on the corrosponding pistons, and a matching contact mark on the valves. A-ha.

So I have ordered two intake valves from (thanks for the recommendation) RockAuto, and will continue cleaning up stuff while waiting for their arrival. Now is a great opportunity to clean the engine compartment and other detail work.

I could read a book on these engines, and I could read this forum for days, but nothing has shown me how these trucks/engines are built, better than hands-on getting into them. There were some fears of the "unknown" aspects, but taking my time, and using common sense, has taught me bunches about my little truck. Not only that, but I can work on it with better confidence in the future.

[meandmit]

great story's Royster...keep them up