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An Aussie 638 engine rebuild project.

39K views 132 replies 18 participants last post by  Gixxe -Pat 
#1 · (Edited)
Hello everyone :thumbsup:

It might be worthwhile to post up my current project.

This 638 is a 2000 model, 2.2 cdi turbo. Manual.

It's done 264,000 km.

I'm a carpenter and thought I'd get a van. I don't really need it for work, definitely can do without it, but like the idea of it anyway. I will use it for work and other stuff. The shape and look of the 638 has been alluring me for a while. Sexy to me :D

I've done quite a few mechanical projects but this is my first diesel ever. Hopefully by the end of this rebuild I will have fair understanding of them and hoping you lot will advise along the way.

Here is a pic I took of it when I got it home. Paid 2 grand to a mate for it not running. He's a close friend that needs some dough so didn't haggle him. Rolled the dice on it, but calculated another engine into the deal. Don't really care how the figures end up. Close enough. Whatever.




It had the usual 4th injector dramas. I re-tapped, reseated and fitted a reco injector. Did the usual checks and bought a new battery.

Wouldn't crank. At. All. Bugger. A few ticks and noises sometimes. Played with the electrics for a few nights after work. Did the starter relay positive feed ecu bypass and still wouldn't crank. Grrr.

Then finally one night it started to turn over. Yayyyy. Well, just a short lived celebrating, because now you could crank it until the cows came home. Wouldn't fire.

Took the plastic intake piping off...and uh oh... water was pouring out the top of the pipe that come up from under the engine and into the left hand side of the plastic plenum thingy. You're joking right? Nope :eek:

Undid the rubber hose from the front of that steel under engine air feed from the turbo and fug me. About 5 litres poured out. Crap.

Not real good hey.

My mate had the van sitting out in the open for a couple of years, with none of the inlet plenum thing on it. The bonnet was down but maybe condensation filled it over the years. It baffle us lots. How did all that water go down the turbo inlet :confused: with the bonnet down?

So...water must have also collected into those 4 open inlet pipes that feed into the head right? See why it wouldn't crank? Maybe puddles sitting on top of the pistons...

Tried everything to get it to fire. Engine starter, hot air into the intake. Not a single fire. Ever.


So...



:rotfl:


Here we are tonight :D

Wanna help me totally rebuild this? Start pulling it to bits tomorrow. Planning on a new head, possibly reco turbo, new bearings everywhere, new rings at least (likely pistons, conrods?) rebore, clutch, rubber hoses, reco starter and alternator etc etc.

I love this shape Vito. This will cost more than it will be worth, but so what, I am keeping it.

I had considered just buying a second hand engine for a couple of thousand with a 3 months warranty, but with approx the same money we could rebuild this and it's way more fun and be much better.

It also needs a new windscreen and some other crap to get it road worthy for rego here.

The missus has given me 7 weeks to get it on the road and we'll take it for a 4 day weekend away to test it out.

Wonder if we can make the dead line?


I'll take pics as it gets dismantled. It can't be good. A cup full of water came out first when I drained the sump. Then the most hideous sludge ever.
 
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#2 ·
I look forward the the progress photographs. Maybe the water came from one of the floods over the last few years. Maybe the poor old 638 was under 3 meters of water for a week!
 
#4 ·
Never thought of the flood scenario Scott :eek:

But the van has been parked on a hill since it was put out of commission :confused:

The first thing I checked was to see if the bonnet vents were the culprit, but there is that whacking big plastic intake boot under it, so it's still got us baffled :confused:

Then...well my buddy has upset a few women lately and I put it to him that maybe one of them chucked a hose under there :eek:. But nope, he says they have been all too dumb to know about doing something like that. Haha


This looks a good build thread, can't wait to see the end results

Hi Jonny.

I worked a few hours today (it's Sunday here) to help pay for some of this, and I couldn't wait to get home and rip into. Just having a coffee and about go out and find a spot to put it inside the garage.

Stay tuned :thumbsup:
 
#10 · (Edited)
Number 2 injector came out after about 10 slide hammers :)



Number 1 :crybaby2:

I tried hard folks.

Must have stroked that slide hammer hard approx 500 times :eek:

Got desparate. Did it to the beat of two songs on the radio. Then did it another 69 times in a row cos' this is totally f@#%ed. It's not budging :banghead: F@#% :givemebeer:

Took some more crap off the engine, came back and gave it everything another 50 times with those bloody welding gloves on for protection. Took some more stuff off the engine and did another 50 hard pulls.

Called it quits in frustration, packed up the tools and couldn't resist another go as I was locking the garage and leaving...


...what's that disease called that construction worker's get when they spend too much time on a jack hammer? Cos' I think my fingers have got it now.

It's one piece. I'll try heating it up somehow tomorrow. Any other ideas folks?


Someone told me to record the injector pump drive belt posi when #1 piston is at TDC.
Which is the injector pump in the below pic? Is it C?
Do I have to record the belt posi?




The biggest torx I had was a T50. Which size do I buy tomorrow to fit these 8 bolts arrowed with red? T55? T60?




I had some very lucky moments tonight. There is no explanation of how I ever noticed that there was the tiniest ball bearing that's ever been in my garage lying near a dismantled injector. How I saw it I have no idea. It goes where the arrow points. But was left out of another injector, not the one in the pic. You can just make out the ball bearing, below the socket, just above the injector nipple. Tiny. Close call :D

 
#19 · (Edited)
:thumbsup:

It's nice to be able to claim it all on tax too :)



I spent 2 1/2 hours in the garage tonight.

2 hours dicking around assembling the engine stand and getting the engine on the stand. Made a couple of really stupid rookie mistakes through the proces. hahaha. I blame it on being mega fatigued from long work hours :eek:

Took 20 minutes to get the sump off.

Not much looking wrong in the pics :rolleyes:












Cat vomit looking sludge. mmmm mmmm.

 
#21 · (Edited)
Tickets are cheap now Welshbreed. Head on down and I'll organise a parts washer for you :thumbsup::):D

Spent some more time working on it tonight. Stripped everything off the block and head.

Then realised I could heat up the head with gentle torching through the inlet and exhaust ports in the head :) to help get the stuck injector out.

There's no way in hell I'd trust myself to remember where everything goes without taking a stack of pics of each part as it comes off. You'd have to be a member of Mensa to remember it all, or work on them every day :rolleyes:

So after putting the tools away I thought I'd have another crack at the slide hammer before I call it a night.

Then realised I was either breaking the puller or the injector was budging.

Wooooo hoooo. It's out. Fairly corroded.





Then of course I postponed going inside for a bit. Just had to take that rocker cover off to check it out under there :thumbsup:






The oil over everything is creamy. Plus the cam lobes have a little film of light rust on them in places.




I should record and mark the cam positions to TDC etc, didn't want to do it as tired as I am, so, finally the head will come off tomorrow. Not now.

Stay tuned, will it look brand new under there?
 
#25 ·
It's good you like it. Thanks. Makes it worth posting it up if some others are getting something out of it.

I have been saved by a few threads over the years after googling my mechanical problem of the time. Maybe this thread will help someone out heaps one day. Hope so.

I got 4 other other motorbicycles behind that Kato SX in the pics. I have two KTMs. I get asked out riding quite a bit, or to lead a group ride, but haven't been out for about 5 weeks now :( This project's not helping. Half the reason for the van is for bike transport, sick of trailering bikes.



Looking good so far.

Thanks for the info. I a bit of a hack at times. Just a carpenter. lol.

Going back to page one photos, your clutch does not need replacement unless the disc is worn.

Those diaphragm fingers are like that from new.

Really? That's crazy.:confused:

My S/H engine is going from the Manual Scrapper Van and into my V Class Bus with it's original Auto Gearbox and the Diaphragm is the same as yours.

I've also pulled a clutch out on a Vito for a customer this week, and that too is the same ;)

If you look closely you will see that the release bearing has never rubbed on those 3 fingers, they are meant to be like that ;)

While I was inspecting the fingers the other night I did notice there were no obvious wear marks on those three fingers. I actually just presumed then that the fingers broke very early in it's life :rolleyes: Very very good info. I will take the whole lot in for someone to inspect for me then. I appreciate you may have just saved me a bunch of dough that could go somewhere else on this.

Keep up the good work, I'll try and get my own "Engines Out" thread going this weekend, have taken some pics of stripping the Black Scrapper so far

I look very much forward to your thread :thumbsup:

Have you a record of which cylinders your injectors came out of, as some say they should remain in the same cylinders as they may need re coding in the ecu if they go back different !!

Amazingly, yes, I engraved the numbers as I removed the injectors. I thought it probably was not necessary but did it just in case :)

See some of my other posts re Injector Coding ;)

Yes. I will check it out for sure.

Cheers Dave
Much thanks for the info Dave. I'm very grateful for you and others sharing your expertise :thumbsup:

Have you looked at a gasket set? I got a price from Bursons today for my petrol and they were $137 for the head gasket and $470 for the kit :eek:
No. I haven't looked yet :( That is a fair chunk of cash :crybaby2: Thanks for the heads up.

I also want a new water pump, alternator, turbo looks bad... Damn. Lol.

Plus, I am also modifying a Jeep Grand Cherokee at the same time and waiting for a container to get here from the US with a stack of bits for it. It doesn't end.

I need to take up some boring cheap hobbies. Like cards or something :rolleyes: Why do some of us do this to ourselves?
 
#23 · (Edited)
Looking good so far.

Going back to page one photos, your clutch does not need replacement unless the disc is worn.

Those diaphragm fingers are like that from new.

My S/H engine is going from the Manual Scrapper Van and into my V Class Bus with it's original Auto Gearbox and the Diaphragm is the same as yours.

I've also pulled a clutch out on a Vito for a customer this week, and that too is the same ;)

If you look closely you will see that the release bearing has never rubbed on those 3 fingers, they are meant to be like that ;)

Keep up the good work, I'll try and get my own "Engines Out" thread going this weekend, have taken some pics of stripping the Black Scrapper so far

Have you a record of which cylinders your injectors came out of, as some say they should remain in the same cylinders as they may need re coding in the ecu if they go back different !!

See some of my other posts re Injector Coding ;)

Cheers Dave
 
#26 · (Edited)
More dismantlement

When was a young bloke, on my first 4 stroke rebuild I made the mistake of not recording the cam posi to TDC. Oh boy...lesson learnt :eek: The memory will always haunt me. Ouch.


I gots no workshop manual for this, so...

I poked a rod down #1 injector hole and marked 20mm up from an estimated TDC, rocking the crank back and forward.



Then, on the crankshaft pulley, marked on masking tape the position when the 20mm mark lined up with the top of the hole. Then rotated back past TDC and onto the 20mm rod mark again, marking on another bit of masking tape that position also.

This gave 2 fairly accurate opposing references to halve, and mark the TDC on a 3rd tab of masking tape.



I positioned the crank shaft to my calculated TDC on it's firing stroke (worked out by the cam positions) and started searching for some sort of factory cam mark or something.

Found it :D

This hole on the inlet cam sprocket...



...lined up 100% smack on with this hole on the inlet camshaft journal directly behind it. Probably a 6mm hole to stick something in and through, to hold it in posi while you line things up.

One of the three exhaust cam sprocket bolts lines up perfectly centre on top of the cam journal cap thingy. You'd have to be a bit silly to get it mixed up with the other two bolts. The cam lobe posi is a give away to picking the right bolt to line up on reassembly :thumbsup:



Hopefully I'm getting this right. Gunna look real dumb to possibly everyone in the world who can access the net... if I'm wrong. lol. :eek:


So now that's recorded, let's get the head off.

But how dumb am I? Where's the head bolts :confused: Thought I was going mental to be honest. Notice the cam journal tops are numbered. Got it recorded for later.



Took the cams out.



Then noticed the cams sit in a removable assembly that also holds valve pusher piston thingies (Lol. Got no idea have I? haha)






Tray removed.



Went to undo the head bolts, in the above pic, and found the torx socket for this size is only 3/8 drive :confused: The only 3/8 socket set I have cost 5 bucks :eek: It would break for sure guaranteed. So I could either wait until tomorrow night and come back with a stronger 3/8 set or make a 1/2 inch adaptor... While my brain was working out what to do my legs were already walking the socket towards the welder.

The heads coming off tonight, whatever it takes :thumbsup:



16mm 1/2 drive socket welded to torx 3/8 drive. Fixed :D


Ta da. Hi res. For close web inspection. Click on for big pics.







The close up of the piston on it's own is the 4th, which was the one with the injector missing for a couple of years of storage. It is also the bore with the roughest condition.

Lots of gunk hey. This engine had to come out for a rebuild after all.

Off to the local engine bloke tomorrow for a verdict on it. Looks re-buildable to you guys?

Back soon. Take care.

Cheers

Dave
 
#29 ·
Thanks Ltr:thumbsup:

Ooo. One of the previous owners played with the air con and no gas in it.
But you'd have to be Hudini to leave the lines intact and get the engine out.

I wanted to keep it all together, the AC that is, and see if it could be saved but couldn't do it.

Might not have ac in the end of this. I have seen lots of Jeep guys convert thier ac compressors to air compressors. That may be the go in the end. I don't know if it can be done with this one though.

Looks like you are doing okay so far, shame about the condition of the engine though. Looks like you are going to need at least a couple new liners, might be a chance to increase the piston size. Also those metal short shot like glasses things are called buckets. But they go by other names too, but I cannot remember them off the top of my head.

Keep going and don't get depressed lol
Ahhh yes, buckets. Thanks WB :thumbsup:

I'm under the pump and trying to make an hour to take the block and head to the engine builder across town. Can't wait to hear the options on it:thumbsup:

Is there any benefit of putting a bigger turbo on it? For example...
 
#28 ·
Looks like you are doing okay so far, shame about the condition of the engine though. Looks like you are going to need at least a couple new liners, might be a chance to increase the piston size. Also those metal short shot like glasses things are called buckets. But they go by other names too, but I cannot remember them off the top of my head.

Keep going and don't get depressed lol
 
#30 ·
Brand new Borg and Beck Clutch arrived Thursday for that customers van...............

3 fingers down low.............So what I said is def correct LOL.

Cam Followers............Hydraulic Tappets...........Buckets LOL

Just going from the photos, I reckon a very light hone and new rings might sort that block if the pistons are OK when cleaned up ;)

Hopefully your engineery man will confirm ;)

Cheers Dave
 
#34 ·
Good on ya, Zbooh, for getting into it. As you know, we're not spoiled for choice in Oz for clued-up servicing/ rebuilding of these, unless we close our eyes and take an MB reaming. I hope you can sort it out fairly painlessly :thumbsup:
 
#35 ·
I much appreciate all the info and advice from all in the posts. Thanks heaps.

I am absolutley flat out with work at the moment, finding it hard to take time out to bring the block and head to the engine gurus here.

I'll give them a call tomorrow, maybe they can pick it up from me for a small fee or something. I'm busting to see what they think.

Want this on the road as quick as possible.


I was talking to a mate at work yesterday about fixing up this van, and long story short he has two 638 Vito vans just sitting there :) He snapped an injector hold down bolt and is over it...went and bought a new ute instead. Lol.
Might go check them out soon :D His two Vitos that is. Not utes. Lol
 
#36 ·
Hi Zbooh, I just stumbled across your thread while I was looking for some info on speedo calibration.
Well mate, your in for a ride! Stick with it, the satisfaction you will get when driving your Vito will make it all worthwhile.
I was where you are 2 years ago. Bought a non-runner that had a blown head gasket that was sitting for nearly 2 years.
Your posts are déjà-vu for me. I will give you the fruits of my experience, not maybes or possibles.
First, a few tips.
Rusted injectors come out easier after an overnight soaking with CLR or similar if corroded. CLR dissolves rust.
If they are stuck because of carbon leaking from the copper washers, use acetone (straight). It is the main active ingredient in carry cleaner. It melts carbon like butter.
Pistons don't come in oversized, so if the bore is damaged, it will probably need machining out and new liners pressed in and then machined to the new pistons.
I recommend replacing the flywheel, clutch assembly. Not because of the 'bent' fingers, they are like that from new, but because the dual mass flywheel will be near end of life so it makes sense.
There are more timing marks on the cams, I will upload my photos when I get a chance.
Also, don't skimp on injectors. Don't buy reco. They usually only get a clean and new tips ( nozzles). Get new injectors. Very important for optimum efficiency.
Also very important, make sure your fuel tank is CLEAN. If in doubt, remove it and clean it. Same goes for the rest of the fuel system. Replace any dodgy plastic fuel lines, they are relatively cheap, flush with clean diesel all remaining lines and have the lift pump and high pressure pump cleaned and checked before you try and use them. (Replace them both if there was any water in the system).
Lastly, we'll done by not smashing your rocker cover. They are getting harder to find used and Merc want an arm and a leg for a new one.
 
#37 ·
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#38 ·
I should try and be more clear. Mercedes Benz don't list oversized pistons for this motor. When I rebuilt my engine I searched for oversized pistons. Result, none from MB.
Oversized pistons from 3rd party suppliers were available, but I wanted genuine.
The ones on your link look OK. Cheap too.
Also, from MB, the pistons come in 2 sizes for the gudgeon pins, 27 and 30 mm. Mine were 27mm. I ordered a new set from MB that came from Germany. Waited 2weeks. The pistons that came were 30mm gudgeon. (Dang!)
I was about to send them back when I got a call from my engineer. 2 of my con rods were slightly twisted and could not be used so I sourced a 2nd hand set from a wrecker that happened to be 30mm gudgeons. Problem resolved itself!
Zbooh my not need new pistons, just rings and a hone. My pistons were seized in the block and needed a sledge hammer to get them out. That's why they needed replacing.
Crankshaft and big end bearings do come in undersizes from MB.
This is not a cheap engine to rebuild. I didn't want to risk any sub-standard parts and went genuine for all internal engine parts. ( pistons, rings, bearings, timing chain, timing chain guides, etc) You can go 3rd party on the ancillary stuff like water pump, alternator, belt pulleys, etc. They are easy to replace if they fail prematurely.
I am speaking from experience. I tried to save a few bucks on the belt tensioner and belt idler pulley. They both started to chew the belt after about 8 months. I have since bought better replacements and a new belt.
When you're buying the parts for the rebuild, the costs mount very quickly. It's easy to try and save a few bucks by getting the ' slightly' cheaper part. That's OK, but not for the guts of the engine. That's my advice.
 
#39 ·
Devito and Dave thanks for your input. You are helping out big time for sure :thumbsup::thumbsup::thumbsup:

I do appreciate it. Always love seeing a post to read in here :thumbsup: Learning lots from you lot.

I'm thinking to not skimp with anything on this engine. I have massive hands and totally have no idea how I'd be ever able to change a water pump, alternator, turbo etc etc without taking the engine out :confused: There's no room at all in there hey.

One question I want answered is: Is it possible/practical to change a clutch on these without removing the engine?

Actually, what other parts need engine removal to replace? Because it's those bits that should be in brilliant condition no?


It feels like I'm letting everyone down because I still have no more news because the block and head are still in my garage :eek: I've even been too occupied to make calls during business hours.

I have enough dough for a new head this week, so really keen for that right now.

Hopefully I can get away for a few hours early next week, we are just about to hand over a section of the housing development to the new owners to move in. Tonnes of pressure for a few weeks. Just. A. Few. More. Days. Lol.

The people I work for, and others, think I should just buy a new or near new Vito and be done with it...but...
A/ One car repayment is enough at the moment.
B/ The 638 shape just keeps getting sexier to me every week the more I see other vans.
C/ Anyone can take the easy way out and walk into a car yard.
and
D/ By the time this is done and on the road I'll know everything about these :thumbsup:
 
#40 ·
Auto part Automotive engine part Metal Nut Fastener

Here are the timing marks I was telling you about. They are located behind the 3rd cam bearing caps. This is how they line up at TDC.

Auto part Disc brake Vehicle brake Wheel Rotor

These dots on the cam gears are lined up like this at TDC.

Auto part Engine Automotive engine part Machine Rotor

Another view. Sharp eyes will notice I used a pin punch of the right diameter (right side of pic) to lock the cams, using the hole you mentioned in an earlier post, while I fitted the chain, tensioners, etc.
The harmonic balancer (crankshaft pulley) should be lined up with O/T and the line on the timing case. This is where it all stays until you're ready to fire it up. The high pressure fuel pump does not need to be timed. Just line up the drive shaft of the pump to the drive cog and slide it in! :thumbsup:


http://www.benzworld.org/forums/attachment.php?attachmentid=1049826&stc=1&d=1406211286
This pic is just for some motivation.:big laugh:
 

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#42 ·
Zbooh, the same people who don't understand your commitment, will wet their pants every time they see an old Kombi on the road. Without guys like you, Devito, the others on this forum and all the other old vehicle enthusiasts, the roads would be very dull indeed...
 
#43 ·
Thanks for the pics even more info Devito:thumbsup: You and everyone else in here are still helping with the motivation :)

Jonny, 3 hours sounds brilliant. Especially after 12 :eek: That type of scenario is easy to relate to. Been there a few times with things. You can probably do it blindfolded now :)

Jimmy, your comment about combis is bizarre. ESP maybe :confused: I have never ever picked up a classic VW mag...until yesterday. Lol. Just happened to be at a cafe we had a break at. Opened it up and was blown away by the aftermarket vw scene. Insanely cheap. Got me thinking. Thinking hard. So simple to work on, tonnes of aftermarket supply...but nuh uh. I want the Vito :)



So anyways, I worked a tonne of hours on Saturday and Sunday so I could take today (Monday here) off guilt free ;)
The idea was to spend the day relaxing while finally taking the engine in to the rebuilders.
Well, that idea went out the window when my missis smashed her car over a traffic island, inadvertantly hugely cracked the cast aluminium sump, losing all the oil, :mad::mad::banghead::banghead: But ever so lucky I drove it next and caught it. Phew.

The Vito head and block are finally at the engine builders :thumbsup::thumbsup:
They'll be pulling it down at the end of the week and let me know the options with it. Have to sit tight until then. He did say that they fully rebuilt one a little while ago and the bill was 7000 dollars :eek: OMG!!!

There was no way I was paying a mechanic to fix the missus's sump then. Need the dough for the Vito. Lol. Holden wanted $800 for the cast ally sump :eek: I found a much cheaper used one and chucked it in myself. Nightmare job but hey, NEED. MONEY. FOR. VITO :(
 
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