Hi Everyone - this is my first post here and before I start, having read pages and pages and pages of great information thus far, let me say wow what a forum. I look forward to our interactions here.
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Okay so we are not in a Mercedes car - My wife and I are in a mercedes 410d chassis base vehicle that was made in to a motorhome by a german company called Hymer in 1993.
She has a OM602.940 engine and a 722.393 tranny. 280,000kms.
Both are suspected in the current crime wave of problems associated with us being a little stuck here at Lake Atitlan in Guatemala (I know there are worse places to be stuck - thats for sure).
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We have no turbo, EGR or other fancy stuff just a bosch IP, 5 cylinders and 2.9l of go - or at the moment not so much go.
We weigh 4.6 metric tonnes fully laden with water, waste water, propane and us - we can reduce that by 250kg with no water and waste.
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Problem:
Mountains - steep ones - huge steep ones, but I used to drive the chassis vehicle (410d panel van) in the 90s and, with a manual box, they go, slowly, up anything.
But we are not going slowly up anything other than a shallow 10° to 15° incline and certainly cant make the 30°+ slopes.
This has got worse in the last couple 1000 kms.
Also we are producing a lot of white smoke under high load - smells like diesel.
Summary:
We do not have enough power going to the wheels to make the hills and this vehicle should be able to do this albeit very slowly.
So is it 1: Engine down on power to the tranny OR 2: The tranny not passing enough power through to the wheels OR 3: A mix of the 2!
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What I have determined so far:
1: There is a good vacuum at the tranny modulator
2: There is no ATF in the vacuum pipe whilst running when I pull off the pipe from the modulator - am I right in thinking that I would see wetness in the vacuum pipe when I pull it off the modulator (ie white smoke is not burning ATF)
3: The correct ATF is in use and it is at the correct level
4: The accerator linkages are old and worn but I have adjusted the slack out of them and corrected the bowden cable and it has made no difference
5: Suggested tranny problem is that the Brake Band B2 is not engaging fully - suggested fault B2 Piston and actuator pin combo
6: Diagnosis info - on the flat or shallow incline we pull away in first and can tell that the tranny changes from 1 to 2 to 3 to 4 okay - smooth changes
7: Diagnosis info - on the same steep hills we can't go forward we can go up in reverse no problem
8: When coming down the same steep hills (forward!) the van has a 1st gear selector position - microswitch - which engages and I have electrically tested the microswitch which is good BUT we cant hold first and the tranny changes up to 2nd at normal speed which when you want engine braking to hold your speed down is quite scary.
9: The gearbox has had a recent (300kms ago) oil and filter change and there were no lumps or pieces in the pan
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The engine then:
1: Starts on the button first time every time
2: There is a glow plug not working - just one and so after starting she runs lumpy till a low temp is reached then very even after that - but have been so nervous of breaking the glowplug during removal and the fact that she starts on the button even in minus 0 temps means that I have never risked that.
3: The white smoke at start up - smells like unburned diesel ( i think) doesnt go away when warm - stays the same
4: No black smoke ever
5: Cleaned air filters and checked for blockages in the air intake mainfold - all good
6: checked cam timing and belt is at 3° ATDC - within tolerance for a used belt
7: There is and always has been a small lag between pressing accelerator pedal and the revs coming up - not much but seems like enough to mention
8: There is a small amount of smoke coming out of the rocker cover breather when remove the breather pipe which doesnt increase with revs
9: No pressure on palm of hand when held loosely over the oil filler pipe with the cap removed.
10: Absolutely no loss of coolant - ever - she has had a completely new cooling system in the last 10k kms - water pump, thermostat, temp sender and in the last 20k kms new rad and viscous fan clutch.
11: No oil slick on top of the coolant in the rad
12: temperature guage reads temps that are consistant and vary as expected depending on the incline and ambient air temperature.
13: Fuel sender unit crud guaze in tank cleaned out 4000kms ago and then 300kms ago tank was taken off and cleaned out completely.
14: New fuel filter and inline filter 300kms ago - inline filter still completely clean.
15: We did run with air in the fuel system for several 100kms without knowing getting less and less power until the van finally gave up and died near the grand canyon - that was when the sender unit in the tank was cleaned and all fuel connections were removed replaced and/or remade.
16: With Engine running and warm - I have cracked each of the injectors and a: there is a similar amount of spurt of fuel and b: the effect on the engine note is exactly the same for all injectors c: Cracking the injector lines didnt change the smoking exhaust.
17: I have a temperature gun and the exhaust pipes for each cylinder on the manifold were measured 2" out from the block (at idle at op temp but NOT after a run) at:
cyl 1 - 77°C
cyl 2 - 84°C
cyl 3 - 84°C
cyl 4 - 86°C
cyl 5 - 84°C

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So anyone got any suggestions please.
I am trying to get an order together from Mercedes in the UK (Bristol where we are from) and trying to find a fine line between not ordering things we dont need and ordering too much. Because of the cost of shipping with weight and then not ordering enough because of the time lag between ordering and delivery.
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I have decided to order a new B2 piston and actuator pin set.

Then there are the tools to do a compression test maybe?

A vacuum test kit might be useful and also a fuel pressure test kit as I am wondering if we stressed out the lift pump or fuel pump near the grand canyon and now one of them has finally given up the ghost - but it would be good to know if the fuel pressures were correct anyway after a 280,000km lifetime.

I am wondering about the injectors too - I will order a set of new nozzles - are these easy to fit for a methodical, practical novice?

I am also wondering about the IP timing - having read so much on here about its effect on power and also about advancing (?) to counteract the effect of chain stretch.

Could anyone let me know the correct IP timing ° - I cant seem to find an actual listed number - although I have seen 14° ATDC +/-1° somewhere on my Google orientated late nights

I have basic tools here and am ordering a parcel from the UK at the beginning of next week in which I will put anything that I will need in terms of non-standard tools - like for some reason my wrench set doesnt contain a 14mm open spanner - Injector pipe nut!!
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Any and all advice will be greatfully recieved, many thanks in advance
Regards
Mark and Saskia

I'm surprise no body has reply to your thread there is a lot of guys here with knowledge on Mercedes diesels the only think that comes to my mind right now is to check if the injection pump is getting enough vacuum that happen to me on my 603 and it didn't have enough power a problem like you are having. You might also look for a diesel mechanic I know there are good mechanics in Guatemala City my cousin lives down there and he owns a samyong power by a 602 n/a and the van goes over steep hills

Oops... Didnt notice it was a 602. So here are some thoughts:

1) Definitely try disconnecting the exhaust, to test for a blockage. It's easy enough and if it fixes the problem, you will know exactly what to do.

2) Most of the 602 issues I've had are in the head...bad lifters, worn valve seats, bad headgasket. A compression check would be useful. Would you have the facilities to pull the head and have it machined?

3) I'd just replace the fuel pump. By the time you test pressure, fiddle with springs, etc, you could have installed a new one and moved on.

4) Installing new injectors is comparable to installing spark plugs. There are vendors who can supply them pop tested and matched, if that's your concern. New Bosch injectors are going to be good enough right out of the box.

5) Is there some sort of barometric compensator on the IP? Maybe it's adjustable.

6) As a rough check on chain stretch, open the inspection port on the IP and rotate the engine (clockwise) until the timing bump is centered in the port. Then check the timing marks...around 14 or 15 is probably good, although someone who knows the 2.9 might have a better spec. If it's off by more than a couple of degrees, consider a new chain.

The grey smoke has me wondering. Maybe a weak fuel pressure relief valve?http://www.peachparts.com/shopforum/diesel-discussion/247039-fuel-injection-pump-starvation-good-lift-pump.html#post2133911

If you cannot drive up hills forward that you can back up is the transmission slipping?

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

HI and thanks for taking the time to read my rambling post and offer your excellent suggestions.
benzguy300 - you know someone down here and they might have access to good mechanics in Guat city - that's very good to know. We will bear it in mind. I am ordering some tools from the uk along with the tranny parts and one of them will be a vacuum test kit - so I will take a look at the vacuum at the IP - thank you.
Mxfrank - thanks for the list. I didnt think about the exhaust and thats easy so will do that even if only to eliminate and as you say it could be the problem and then an easy fix - I ma guessing here that you mean detach everything after the manifoild and then work through it all bit by bit looking for blockages?
The top engine rebuild stuff we are leaving until we have totally discounted the rest of the possibilities - mainly due to finding a trusted engineering workshop here for the precision boring and grinding should we need it ... and the painful process of paying for it too.
The lift pump is a big suspect but the parts all have to come from the USA or Europe so for now we are focussing on the B2 brake band piston and with those parts will come a fuel pressure test kit so we will have the means to be able to measure it first before ordering and fitting, I agree though if I was back in the UK I would probably just get one and slap it on.
New injectors are coming in the parcel with the brake band piston so I will be learning how to do that very soon
The IP does have a barimetric compensator and as yet I cannot find out how to test if its working or not - like with all these old Mercs I am sure its been here since the van was made!
The chain stretch and fuel pump timing checking is something that I am quite a long way from understanding ... but I am a fast learner. I have set TDC and seen to 3° mark on the crank markings so chain SHOULD be within tolerance (unless some bright spark PO/mech moved the marking pointer). It is something that I would like to do - advance the timing by 2° and see whether it makes a difference ... seems a lot of people recommend it for small errors from chain stretch.
SD Blue - I read about the fuel pump pressure relief valve only yesterday and need to follow up on this - thanks for the link again - as you can imagine I have about 100 tabs open on the laptop at any onetime and keeping track of what piece of info is where is not easy When the tranny is proven again then the white smoke and loss of power will be the next parcel of parts from USA or europe ...
t walgamuth - That seems to be the suggestion so far - we are getting a replacement B2 piston and actuator pins of all lengths and new seals. Then once it all arrives I will fit the piston and the next size pin up and see what difference it makes - if not then the next size etc etc We are camped in a field so I am loathe to take off the body inside the tranny unless i have to ... so I cant do the measurement of the b2 brake band play and calculate the pin accordingly. Accessing the B2 through the side of the tranny reduces the risk of wind blown dirt entering the tranny box. Current thinking is that the movement on the B2 band is way way too much for the factory fitted pin - 47.2mm - I have pushed the bottom of the band and the travel inside the box to my finger is 11mm - recommended play is around 5.5mm - but without x-ray vision I cant see how much re-assembling the piston pushes on the brake band and therefore how much actual play there is for the actuator pin to take up. This way seems a little upside down but is dictated by our place of residence - no nice clean indoor workshop (I so wish).
Thank you all for the suggestions and anyone else that wanders in here I am learning so much everyday that there is always room for more advice from those who know.
We know that the van is under powered and with a potential fault in the tranny it explains our lack of mountain climbing power. But once the tranny is back to scratch it really is time to address the engine problems. Especially as we have another 2 years of travel to do and climbs in the Andes of over 4000m above sea level.
I look forward to your further suggestions and I will keep this thread posted with my progress. Regards Mark and Saskia - Guatemala

Have you ever dealt with hills as steep as you are experiencing now in the past with this vehicle? Even one? I was also wondering if the white smoke may be a cylinder problem.

Since you are obviously far from home with few tools perhaps a service shop can help. They probably are far more familiar with Mercedes in that region than in north America in general.

I assume you changed all the fuel filters and you know it is not just bad fuel? As long as the engine is not revving high with little forward movement compared to what was it probably is not the transmission.

The excess white smoke in general is highly indicative of some form of issue with the engine as well. I could see excess black smoke under heavy loading but not white.

Old trick to get a better gear ratio. Actually common before yours and my time Tom. The white smoke should not be present. Whatever is causing it has to go. I was even wondering about water in the fuel. It could massively reduce power and turn to steam. Seeing if it condenses on a mirror behind the tailpipe would tell one way or another.


With no actual water separator on most Mercedes I might drop the secondary filter and drain it into a clear glass article and see what I had. That white smoke is coming from something.

Check fuel filters.

Drain some fuel into a tall glass jar and let sit and separate. See what you got. Look at it. Smell it.

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Greg
2012 S350 BlueTEC 4Matic
2007 ML 320 CDI
2007 Leisure Travel Serenity
2006 Sprinter 432k
2005 E320 CDI
1998 SLK230 (teal)
1998 SLK230 (silver)
1996 E300D 99k, 30k on WVO
Previous:
1983 240D, on WVO
1982 300D, on WVO
1983 300CD, on WVO
1986 300SDL 237k, 25k on WVO (Deerslayer)
1991 350SDL 249k, 56k on WVO - Retired to a car spa in Phoenix
1983 380 SEC w/603 diesel, 8k on WVO
1996 E300D 351k, 177k on WVO

My dad told tales of backing up hills with the T and A fords. Also works when the gas level in the gravity fed tank is getting low.

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Agreed, considering the locale, water in the fuel could be a very real possibility.

BTW, the T and A Fords probably climbed the hills at the same speed, regardless of forward or reverse......s-l-o-w. (20hp with top speed of 45 or you could really fly with 40hp of the Model A.)

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Sam

84 300SD 350K+ miles ( Blue Belle )

Depending on your altitude the manually aspired diesels do lose some power remember as well. Anyways fixate on the obvious observable fault first. You should not be producing the white smoke.

Whatever is causing it has to be found first. Simply because the cause of it could be all of your problem. Never ignore the obvious first.

Hi All
Wow thanks for the continued input. All very poignant points.
The only reason we are focussing on the tranny is that we already have had big problems with it over the last 20,000 kms and naturally it seemed that that was the place to investigate.
The white smoke and the lack of hill climbing power are all new to here in Guatemala. We havent particularly noticed any hil climbing problems before but the these are also the steepest hills we have climbed in the last 28,000kms ...
The van has always smoked on start and never really cleared up whern warm but it hasn't got any worse yet and the new amount of smoke only happens when the van stops on a steep incline at high load.
I tried the condensation thing and there was no hint that it was steam - the smell of the smoke is more acrid - seemingly its unburned diesel - hence the timing of the IP being a suggested option.
There are so many things that it could be I just really dont know enough to test them and rule them out or not and then try and fix them.
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Focus on the observable problems first - agreed.
So I have read on here that white smoke that smells of diesel can be bad valve adjusters, bad IP timing and steam amongst other things.
Pretty much ruled out water from our engine but water in the fuel is a possibility - I will syphon some from the tank and let it sit to see.
Comression test is a necessity but I need to get out of here first and get to a good mechanic to get one done (dont have compressed air here)
Thanks guys and keep the suggestions coming much appreciated.
regards
mark

my first move would be to adjust the valves. maybe you have, but you didn't say.

once it is running well again, adjusting the ALDA may give you a little more oomph.

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'77 240D, 504H, OM617.952, etc.

6: checked cam timing and belt is at 3° ATDC - within tolerance for a used belt

3 degrees I recall being the maximum allowable timing chain streach on a 602 na engine.
That is a possible cause of white smoke.

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92 e300d2.5t
01 e320
05 cdi
85 chev c10