Help needed - turbo help please (diesel engine)

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Donnie
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Help needed - turbo help please (diesel engine)

Post by Donnie » Wed Mar 25, 2020 5:34 pm

Right, dont think the turbo is working much on my bongo, theres no real oomph and so far ive removed the heatshield and run the engine looking at the actuator rod and it barely moves when revving, maybe 2mm.

Imagepasslayout1 by Donnie Canning, on Flickr

So, a photo to get my bearings of under the passenger seat of my P reg 2.5 diesel bongo

1. Waste Gate Actuator Rod
2. This is where the rod moves the wastegate i assume?
3. Air intake Hose
4. Pipe to connect to external vacuum that Pete Fordham mentioned earlier?
5. There's a nut behind here, its not loose but the whole pipe moves on there about 5mm so obviously needs tighening.
6. Is this the infamous front exhaust nut that goes pop?
7. From Air Funnel? connected at 5 which is loose.
Im thinking if i remove the wastegate rod at 2 (there's a large e clip on there) then if it's not seized then I should be able to move it easily? And probably move the rod seperately too?
'96 AWD 2.5 diesel with AFT
Donnie
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Re: Help needed - turbo help please (diesel engine)

Post by Donnie » Wed Mar 25, 2020 6:45 pm

Ended up using a 17mm spanner
You can hear it being a bit creaky at first, and was hard to move initially but now is lovely and smooth.

https://www.youtube.com/watch?v=kkl8HDz ... e=youtu.be
'96 AWD 2.5 diesel with AFT
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Northern Bongolow
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Re: Help needed - turbo help please (diesel engine)

Post by Northern Bongolow » Wed Mar 25, 2020 7:35 pm

That's number 2 manifold stud indicated, number 1 is forward of that position and on the underside row, same engine/ head outlet, but lower on the head..
Donnie
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Re: Help needed - turbo help please (diesel engine)

Post by Donnie » Wed Mar 25, 2020 7:58 pm

Northern Bongolow wrote: Wed Mar 25, 2020 7:35 pm That's number 2 manifold stud indicated, number 1 is forward of that position and on the underside row, same engine/ head outlet, but lower on the head..
ahhhhh, of course it would be too easy :-) So, how would I check it's ok or not?
'96 AWD 2.5 diesel with AFT
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Northern Bongolow
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Re: Help needed - turbo help please (diesel engine)

Post by Northern Bongolow » Thu Mar 26, 2020 10:57 am

Just stick a socket on it and gently try to tighten, don't go mad or it may break. Be prepared for that sinking feeling when it snaps, sometimes they are snapped and just sat there, other times they fall out altogether.
Good luck.
Donnie
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Re: Help needed - turbo help please (diesel engine)

Post by Donnie » Thu Mar 26, 2020 1:46 pm

Sorry for the blurry pic but Im assuming where the arrow points is the aforementioned problem bolt / stud? Especially as it looks like its already been snapped off at some point :-(

Is this something I can tackle at home? Im assuming its turbo and exhaust manifold off then extract the stud?

ImageIMG_3011 by Donnie Canning, on Flickr
'96 AWD 2.5 diesel with AFT
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JulesMartin
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Re: Help needed - turbo help please (diesel engine)

Post by JulesMartin » Thu Mar 26, 2020 1:55 pm

If you're pretty accurate and have really good drill bits it can be drilled and re tapped in situ but that won't get round the problem that the manifold is almost certainly warped at either end. my advice would be to remove manifold and turbo put a straight edge along the manifold to see if it's warped which it probably will be. if you have a friendly engineering shop they can skim it for you whilst you concentrate on getting the broken stud/bolts out (you'll note the pluralisation) :( I have read on here somewhere that you can use double gaskets to cure the warp but better to get it done properly IMHO
Martin
1996 2.5 TDi Silver pop top unconverted
Donnie
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Re: Help needed - turbo help please (diesel engine)

Post by Donnie » Thu Mar 26, 2020 2:41 pm

Yeah, just feels like it's one thing after another that needs doing :-(

Also just found https://www.igmaynard.co.uk/bongo/forum ... ifold+stud from Northern Bongolow which is excellent step by step.

I think I will remove the whole thing and get it checked / skimmed and new gasket, anything less wouldn't give me the confidence in it I think.

Now just need to source the right drill bits and extractors.
'96 AWD 2.5 diesel with AFT
Donnie
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Re: Help needed - turbo help please (diesel engine)

Post by Donnie » Thu Mar 26, 2020 2:53 pm

Ive got some plus gas etc but have also seen some vids where people warm up the van first to get some expansion in the head and then make it easier to undo the studs / nuts as it cools? What have people here done?
'96 AWD 2.5 diesel with AFT
Bongolia
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Re: Help needed - turbo help please (diesel engine)

Post by Bongolia » Fri Mar 27, 2020 12:14 am

For my two pence worth. First make sure you have a good fitting socket preferably not a multi point.
Expansion and contraction is the what will do this.
If you have access to a Rothenberger blow lamp, for me an essential bit of kit for all DIY stuff, use this to get the nuts crimson hot then after cooling a bit soak nuts and studs with Plus Gas or dilute engine oil and parrafin.It will smoke like bonkers.
Now try to undo them using controlled force dont be tempted to stick a long bar on. You need to coax them bit by bit if it goes tight retighten a bit and spray with more oil if that doesnt help reheat the nut and start again.

If you have no torch then get engine hot and spray them when it cools try tightening the nuts -not to much force- spray em again and try to undo.
You need to persuade them if its not going then squirt it and try a different one.The trick is not to get to heavy handed.
Once the manifold is off you may be able to coax the busted stud out with a pair of molegrips clamped round the stud if enough is left. If that wont work then you need to drill them.
Two gaskets is a bodge and not a very good one yo need to have the face surfaced. Use a good quality gasket when reassembling. Start the engine get it hot then let it cool overnight and check torques again. Job done.
Goodluck.
P.S. you may find the stud is unscrewing from the head dont worry if this happens you can sort it on the bench after.
Donnie
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Re: Help needed - turbo help please (diesel engine)

Post by Donnie » Fri Mar 27, 2020 12:42 am

Cheers mate, dont have a Rothenberger blow lamp but have a Go System one also gas so that should do I hope.
'96 AWD 2.5 diesel with AFT
Donnie
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Re: Help needed - turbo help please (diesel engine)

Post by Donnie » Fri Mar 27, 2020 2:09 pm

managed to fight the wires etc and get the top engine panel off. Seems a load of extra audio wires there too from a previous installation of some sort of sound system, which is odd as Im sure that the rear speaker wires werent connected when i checked behind the interior panels.

ImageIMG_3014 by Donnie Canning, on Flickr

ImageIMG_3015 by Donnie Canning, on Flickr
'96 AWD 2.5 diesel with AFT
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