505 diesel blowing smoke but not getting full boost

SamT

SamT

Member
Fellow Frogger
Joined
Dec 30, 2012
Messages
97
Location
Kyneton, Victoria
Hi,

Wondering if anyone has any thoughts on improving the performance of my diesel.

I did an engine swap taking out a 2.5l xd3 engine and replacing it with a 2.3l xd2. This engine is smoother but is lacking the pull and performance that the other engine had.

I retained the rebuilt injection pump (Bosch Ve) and have the wastegate disconnected.

The car isn't reaching the boost levels of the other engine and is blowing excessive black smoke under any throttle.

I have played with the fuel and timing like I did to get the performance on the xd3 but I'm having this problem with too much black smoke without getting good boost level. I'm unsure boost pressure level but just going off standard colour GTD gauge on my dash and how the car feels.

Also the car has exhaust resonance approaching 2500 revs. A lot lower in the rev range than the other engine. This means it's not pleasant around the 110km/hr which is annoying.

Thinking I may need to swap the turbo over. This one has a kkk and the previous a garret. Any thoughts? Thanks!


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Gday Sam,

I have no answers, but am on the same journey with my 505 Diesel wagon. I'm also running a 2.3 Turbo with a 3.58 rear end.

Look forward to the replies. Bloody great wagons otherwise!
 
Although I've had two of these XD2 engined 505's in the past, I can't offer opinion apart from an unsatisfying 'too much fuel' and 'possibly not enough air' and 'possibly injector service', or 'timing issue' possibly 'chain stretch'. If you don't get good feedback go over to Super turbo Diesel forum and ask there...there are a few on that forum that know these oil burners well.
One piece of advice however is to be very careful about using the vehicle with excessive EGTs (which are likely present given the outline of symptoms).
HTH
Steu
 
Hi Sam,

Would be interesting to know what boost you're actually getting out of it.

I had problems on my setup when I was running higher boost where the wastegate was getting pushed open by the pressure in the exhaust housing. The pressure in the exhaust manifold between the engine and the turbine is at least the boost pressure.

Since the XD2S runs less boost than the XD3T (7psi vs 11psi), it has a weaker wastegate spring and would be more susceptible to the pressure in the turbine. My solution was so add a line from the vacuum pump to the wastegate actuator and apply vacuum to the back of the wastegate. Assuming everything else is OK, this should give you a fair bit more before it leaks - hard to calculate exactly, because the surface area of the diaphragm is greater than the size of the wastegate itself.

I would strongly recommend getting an accurate boost gauge. It can tell you a lot.
 
Thanks all!

Some great points and tips. I should really go get a boost gauge. Would an Egt gauge be worth it? How does EGT's relate to the engine temp. As in would the exhaust gas temp get dangerous before the engine would overheat?

Thanks Stue for the tip on the super diesel forum. I will look this up. I stripped this engine down and when I out it back together I put in a new timing chain amongst other things. Timing and fuel may still need tweaking thou.

Scott thanks for the info on the wastegate spring!! Your mod may just be the answer. I will know more if I can fit a boost gauge.... step 1 I think.


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Hi SamT. I'm not sure if these engines have EGR systems. If they do, I'd recommend checking that it's not stuck open.
 
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