White Smoke 300tdi Help!

Wilboro

Well-known member
Some of you might recognize my project from over on the "other" forum, but I've run into a problem and I just don't know what to do at this point.

So I'm finishing up the rebuild on my '97 110 300tdi and I noticed two things.

1. Once the exhaust system was fitted I started noticing a bit more white smoke than I remembered. When the engine is brought up to higher revs a lot of white smoke is coming out. It seems to be most just before the waste gate dumps the boost pressure. At low rev's and idle there is very little exhaust but when you do see wisps it's whitish.

2. I thought initially that the coolant in the expansion tank had dropped, however I'm not sure now. The tank had been hanging off the side of the engine with a bungee cord and may have just leaked.
Since refilling to the line and attaching it more securely I can't see any noticeable difference in coolant level after running it multiple times.

The truck has not been run on the road simply driven in and out of my garage and idled for up to half an hour. It doesn't overheat in these circumstances and it starts up and idles smoothly.
There is a small bit of pressure in the rocker, but if you undo the oil filling cap and leave it loose it won't get blown off (bounces a bit).

After inspecting the expansion tank when the truck is running, it looks like there might be some tiny bubbles in tank, but it doesn't seem regular and they are very hard to see.

I've also checked to see if there was any brake fluid in the vacuum hose, I've heard a leak on the master it can push brake fluid into the engine. But the lines are bone dry.

When I bought the truck in Holland I had the head gasket redone as it had an external leak on the 4th cylinder. What exactly was done I can't tell you (was it skimmed? not sure) but there is no sign or sound of an external leak. And it drove with no problems before I took it off the road.

Here are the things I've done that I think could have some sort of bearing on the situation.
I've replaced the fuel lines and tank.
I've replaced the turbo and exhaust gasket(boost pressure has not be tested yet)
I've changed the timing belt (I'm certain all the marks and pins line up) but...
The engine wasn't taken apart other than to replace the t-seals, replace the rear main, re-seal the sump and clean up the intake plenum.
All the hoses for the cooling system, and inter cooler are new.

Anyhow I'm kind of at a loss what I should do next. I know a compression test would be a good idea, and there is combustion test (where the fluid changes colour). I could also do a pressure test on the coolant system.

I don't have any of the tools to do these tests and they don't seem to come too cheap so before I start buying up diagnostic tools I'm looking for some advice with how to proceed from those who are more experienced.

Will
 

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DefendersNW

Well-known member
Sounds like the timing is off - tensioned on the wrong side of the IP most likely.

At idle the "off" is minimal, but under throttle as the speed increases so does the amount of effect from the timing being off.

Pull the front cover, reset the timing using the manual procedure (run through two cycles by hand, loosen, reset, and run through two cycles again to verify that the timing is in place)

Reassemble and test.
 
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Wilboro

Well-known member
Sounds like the timing is off

I'm just looking at pictures of the timing operation I did, and with the pin in the flywheel and a drill bit in the timing pin hole the cam pulley does line up with the mark. I also did check that the marks lined up on the crank pulley too.

So what could have gone wrong here to cause the timing to be off? I mean I'd be happy if this is the case, better than a head gasket or cracked head.
Just trying to understand what could have gone wrong with this operation.

Also would I have other symptoms if the timing was off? Wouldn't it run funny?

Sorry just saw the rest of your response. I did do the two cycles and re-tigthened when installing. When you say tightened on the wrong side of the IP what do you mean?
 
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DefendersNW

Well-known member
So what could have gone wrong here to cause the timing to be off? I mean I'd be happy if this is the case, better than a head gasket or cracked head.
Just trying to understand what could have gone wrong with this operation.

Also would I have other symptoms if the timing was off? Wouldn't it run funny?

Sorry just saw the rest of your response. I did do the two cycles and re-tigthened when installing. When you say tightened on the wrong side of the IP what do you mean?

When you fit the timing belt one side will be slack (to be taken up with the tensioner) and the other side will fit tight (teeth aligned) - if the teeth are aligned on the left side and the slack is taken up from the right side the IP/cam will be off slightly (half tooth) - but if the tension is taken up from the left side (crank to IP side) the cam/crank/ip adjustment stays fixed.

If the timing is slightly off you will have white smoke, (unburned fuel vapor) heat buildup, and power loss under throttle.

Looking through the radiator - check the timing mark on the cam pulley. Double check the crank pulley by verifying the flywheel position through the wading plug hole as well.
 
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Ash

Active member
What does the vapor smell like? If it's coolant you should be able to tell rather easily.

-Ash
 

Wilboro

Well-known member
When you fit the timing belt one side will be slack (to be taken up with the tensioner) and the other side will fit tight (teeth aligned) - if the teeth are aligned on the left side and the slack is taken up from the right side the IP/cam will be off slightly (half tooth) - but if the tension is taken up from the left side (crank to IP side) the cam/crank/ip adjustment stays fixed.

If the timing is slightly off you will have white smoke, (unburned fuel vapor) heat buildup, and power loss under throttle.

Looking through the radiator - check the timing mark on the cam pulley. Double check the crank pulley by verifying the flywheel position through the wading plug hole as well.

Ok I understand... that may have happened. Sounds like this is the place to start for sure. Thank you very much!

I'll report back.
 

javelinadave

Administrator
Staff member
Ash knows of what he speaks. You would absolutely be able to smell the coolant in the exhaust if that was the cause.
 

Ash

Active member
Coolant will have a very distinct sweet smell, assuming you're not running straight water in its current state.

Double check your timing marks like Brian has suggested since it's free peace of mind, and proceed from there. Are you on the original injectors?

-Ash
 

Wilboro

Well-known member
Coolant will have a very distinct sweet smell, assuming you're not running straight water in its current state.

Double check your timing marks like Brian has suggested since it's free peace of mind, and proceed from there. Are you on the original injectors?

-Ash

Yes I'll check the timing first as it does seems more than possible. Certainly no sweet smell and it's on brand new coolant 50/50.

I haven't touched the injectors and no idea as to their age. Can something go wrong with them from sitting?
 

Uncle Douglas

Well-known member
Callsign: delete
100% suspect a timing issue as Brian said. Basically the injectors are firing a tad late.
There is a small amount of adjustment available @ the IP pulley

Tdi injector tips have an average life expectancy of 80-90 k. Bad injector tips typically don't make white smoke. Any Bosch shop can pop test your injectors and check the spray pattern. Injector tips aren't expensive
 
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Wilboro

Well-known member
Attempted to put the flywheel pin and FIP pin in and it was a no go. Pulled the timing case apart and the FIP hub is darn close, but needs to rotate just a tiny bit clockwise to allow the timing pin (9.5mm drill bit) to go in.

Hopefully making this adjustment will solve the smoke problem.

One thing I did notice with the timing case apart, the idler pulley is bleeding a bit of grease out around the seal. Perhaps they were overpacked as it is new... I'll pull it off and clean it up before reassembly.
 

1991Defender110

New member
Hey, I've got a timing pin set out in Almonte if you want to borrow it. From reading the replies it sounds like I might need to adjust the timing ever so slightly on mine too. But before I do I really should put the new fuel tank in.....
Keith
 

Wilboro

Well-known member
Hey, I've got a timing pin set out in Almonte if you want to borrow it. From reading the replies it sounds like I might need to adjust the timing ever so slightly on mine too. But before I do I really should put the new fuel tank in.....
Keith

Thanks for the offer Keith but I managed to get the job done. I actually used a 9.5mm drill bit as the pin (this seems to be a common practice).
Haven't tried running it yet as I'm plumbing in a webasto so haven't refilled with coolant yet. I know I could have adjusted this without draining the system but I wanted to have a look in the timing case and do a few other jobs.

I'll report back once I've fired it up.

Will
 
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