Thread: 200 TDI head problem

Heads back. Looks good.
When the gaskets and new head bolts arrive I can start reassembly.

Had the head machined, valves and seats done.
Spare injector pump recoed and installed. Its worth more than the Disco now.
Took it for a road test and its still a bit gutless.
The last 6 months or so its been down on power, so I installed a boost gauge. Max I could get was about 8 psi.
After all this was done I thought I was right but not so.
Rechecked the injection timing, still spot on.
I am a bit baffled now. Why is it so?
Could it be the turbo?
When I had it off there was a little end play but no side play in the inlet impeller but now flat in second the max boost I get is about 3 psi.
A full throttle at rest test gives me around 4,300 rpm.
I havent been out on the road yet but before the reco max rpm in third was 3000.
Dont know much about turbo,s.
Any ideas out there?

Keith

Originally Posted by 123rover50

Had the head machined, valves and seats done.
Spare injector pump recoed and installed. Its worth more than the Disco now.
Took it for a road test and its still a bit gutless.
The last 6 months or so its been down on power, so I installed a boost gauge. Max I could get was about 8 psi.
After all this was done I thought I was right but not so.
Rechecked the injection timing, still spot on.
I am a bit baffled now. Why is it so?
Could it be the turbo?
When I had it off there was a little end play but no side play in the inlet impeller but now flat in second the max boost I get is about 3 psi.
A full throttle at rest test gives me around 4,300 rpm.
I havent been out on the road yet but before the reco max rpm in third was 3000.
Dont know much about turbo,s.
Any ideas out there?

Keith

Keith, check that the turbo waste gate is working correctly and not stuck open, you should have more boost, also remove and clean/flush out the intercooler and check all of the hoses in the turbo system. By checking hoses I mean remove the hoses inspect inside and out and bend around to see if any are delaminating (layers inside or out peeling away from body of hose), if a hose is coming apart on the inside you have to remove to check properly.
Where do you have the boost gauge plumbed to?, if there is excessive oil in the intercooler, drain it first, then spray at least one can of degreaser in and let sit for a while, Drain properly, then do the same with a couple of cans of Carb/Throttle body cleaner, finally a rinse with some soapy water (not too much soap/detergent), let drain in the sun for a few hours, turning occasionally, then blow out with compressed air.
If you don't know how to test the waste gate find a mechanic that can do it for you, pressure at the air line into diagphram on the waste gate actuator 10 to 15psi should see the valve arm move in and out, you may have to remove turbo to check that the waste gate valve is closing completely, good luck, Regards Frank.

I have the boost gauge T,d into the short hose going to the waste gate actuator as that was the size fitting that came with it.
I thought it would give a true boost reading even if the intercooler was blocked a bit as its before all that.
The lever for the waste gate is free and moves against the spring pressure OK.
Apart from swapping to another turbo I am out of ideas.

Have you applied air pressure to the air line to see if the arm is moving, the Diaphram may be leaking, Regards Frank.

Thats a good idea.
I will try that shortly

Originally Posted by Tank

Have you applied air pressure to the air line to see if the arm is moving, the Diaphram may be leaking, Regards Frank.

Thanks Frank.
Found it.
The air pressure moved the lever OK then I thought it may be too much so pulled the hoses off and blew through them.
Diaphram OK so tried the little hard plastic one to the diaphram on the IP.
Presto, leaking.
Unbolted off the IP , blocked the end and still leaking.
Pulled it off and found a crack in the plastic line.
Fixed it, all good and boost back up to 10PSI again.
I dunno, since I turned 70 my brain seems to be losing it
I am forgetting things that were second nature 10 yrs ago.
Keith

Originally Posted by 123rover50

Thanks Frank.
Found it.
The air pressure moved the lever OK then I thought it may be too much so pulled the hoses off and blew through them.
Diaphram OK so tried the little hard plastic one to the diaphram on the IP.
Presto, leaking.
Unbolted off the IP , blocked the end and still leaking.
Pulled it off and found a crack in the plastic line.
Fixed it, all good and boost back up to 10PSI again.
I dunno, since I turned 70 my brain seems to be losing it
I am forgetting things that were second nature 10 yrs ago.
Keith

Yeh! I know how you feel, I just turned 69, as my son said "dinner for two, with a horrible view" took me a while to get his birthday greeting, Regards frank.