swapping turbo
I have recently acquired a 617 engine with an aftermarket turbo on a G wagen with serious rust problems. I am wanting to take the turbo off this G and put it onto my own G wagen which has a 617 engine as well. Would this engine withstand the turbo, do you think?
The only reason I am wanting to just transfer the turbo and not transplant the engine as a whole is that it is burning a bit oil. Any information on what I have to do please would be greatfully recieved - thanks.
Hi apart from the obvious transfer of the exhaust and inlet manifolds the turbo oil feed and scavenge pipes involve drilling and tapping the base of the oil filter bowl and the top of the sump casing.or swapping both...plus the modification of the exhaust system (larger bore and shorter run) for efficient breathing... if intercooled then the mounting and plumbing of the cooler radiator.......burning oil could be valve guides.....swapping cylinder heads may cure that problem...or turbo seals(look for wet oil in the pipe from the turbo to the inlet manifold)...... finally tweaking the wastegate to give optimum boost......
Actually rebuilding the turbo is a lot easier than rebuilding the engine...
Most of these turbo kits were Garrett T2 turbos.. on USA ebay you can buy seal kits for £50 or so... you do need to pay attention when you pull the compressor wheel from the turbo to ensure it is returned in the same place relative to the shaft/impeller but by all accounts it is doable. I will find out I guess when I light mine up.. did not do a seal kit but rerouted the drain kit and stripped out the seal .. it is very simple.. just a piston ring type seal with a big drain just before it an a disk to throw the oil off...so there will always be a bit of oil by pass on these.. not sure if the later turbo seals became better. Alternative is just to buy the "cartridge" which is the central section with compresssor/bearing/impeller.. but then you need to works out what your actual turbo is..
I would suggest you don't tweak the turbo boost as would increase combustion temperatures and you may need a replacement engine very very soon. The normal 617 engine is not as strong as the original turbo 617A, especially the pre-combustion chambers whose tips can melt and drop into the cylinder if you run on higher boost.
So whatever you do, don't play with a converted engine. Leave it on it's original settings (you need to check them from time to time).
something tells me that pambos speaks from experience.... :(
Tweaking boost needs an EGT (exhaust Gas Temperature) gauge.. that tells you how hard it is running and when to back off under heavy load. Yes 617 is missing oil cooling of piston, lower compression ratio and probably better pistons.. but EGT monitoring will tell you when to back off... just a 617a will take more.
Sure half my post went missing.. 617a is a TA031 turbo but not worked out what a TB and STT are.. so that T2 kit maybe wrong .. (I have one of each ;-) )
Hi Andrew reputable turbo O'haul specialists will probably have an "over the counter" exchange service..TB turbo appear to fit a coventional unit applicable to other engines so not a uncommon type.the injector pump should be set up to reflect the fact that a turbo has beenadded .....no good getting a lot of air and not enough fuel......
:D thanks for all the information.
I'm not doing the actual conversion myself its a mechanic that's doing it but he's never done any work on a g wagen before...
it's amazing the amount of people who don't know what a g wagen is :!:
the conversion is planned to start tomorrow but i'm sure there'll be teething problems before the jobs done so watch this space....
thanks, Andrew
Hi Andrew reputable turbo O'haul specialists will probably have an "over the counter" exchange service..TB turbo appear to fit a coventional unit applicable to other engines so not a uncommon type.the injector pump should be set up to reflect the fact that a turbo has beenadded .....no good getting a lot of air and not enough fuel......
:?: Just a wee question - which part of the injector pump regulates the fuel? As fixwin38 says no point getting loads of air and not enough fuel :?
Thanks, Andrew
Hi Andrew there are three bolts holding the flange of the injector pump to the engine.. if you slacken the bolts and all the "B" nuts on the top of the pump and at the injectors you can rotate the body of the pump towards you (BY DEGREES) as you lean over the near side wing...a piece of timber or a pry bar will give better leverage and finer adjustment.....most engines have a yellow paint dot on the flange of the pump and on the engine casing... move the dot on the pump so that it sits slightly below the original top line of the dot on the casing.or put your own mark before you start to move the pump....it is a bit "hit and miss" but do it by degrees until you can get a small puff of black smoke from the exhaust as you do a quick rev of the engine.you will also get a continuous light tinkling sound from the engine at idle.... best described as rattling small ballbearings in a glass jamjar.in effect what you are doing is bringing slightly more fuel into the combustion chambers at each compression stroke ......resulting in better performance.
Fixwin,
That is just tweaking the timing not the fuel quantity?
To do it properly you need an exhaust temperature gauge (EGT) fitted.. which is what TB turbos do when they set up the injection pump on a rolling road.. that and an eye for black smoke (=too rich).
Some reading .. sorry about the LR reference :oops:
http://www.exploroz.com/Forum/Archive/2005_5/26564.asp
http://www.orrp.com/smf/index.php?topic=4722.0
.. this is going inside the pump to reset the max fuel delivery stop .. timing can then also be played with. I have not done this yet... I suspect Fixwin therefore has more practical experiance.. there is some US write ups but be wary (unless you have a US injection pump) as they have "Aldays" or something which is a different beast for emmisions on their 617a .. plus a real 617a has a pressure chamber on top of the injection pump to tell it the boost pressure which then automatically moves the maximum fuel delivery stop.. So getting a Euro 617a injection pump is the real solution.. but not sure about injector sizes or pressue settings ..so to be sure get injectors at the same time.
Tuning a non turbo injection pump will be a compromise .. really need the boost pressure can of a 617a .. otherwise you will get it running right in about 2 places.. idle and full throttle with compromises/errors in between.
Hi Yes my 617a injector pump is a very different pump to the standard 617 engine configuration..because the 617 turbo retrofit is non factory there is nothing officially written to work to ..trial and you hope very little error is the only way to go..as a compromise to having lots of black smoke when the turbo kicks in bringing the fuel in earlier by changing the timing has proved to be a workable solution.the 617a pump and turbo is getting closer to peaking the 5 cylinder performance but the 617 engine has the wrong pistons anyway.so a "half way house" conversion is probably the best you can expect....
http://www.pointedthree.com/disc/forums/showthread.php?tid=4959&posts=25...
This link has a bit more on messing internally with max fuel stop.. and on a Euro 617 pump. Trouble is you need EGT to start up that road unless you want to kill your engine .. so stay with Fixwin's timing tweak.. still not sure why it does much as you have the same amount of fuel?
Hi it appears that you get the fuel delivery earlier therefore there is more in the chamber before it fires
Thanks for the info guys
:?: would I be safer having the mechanic change the injector pump as well to maybe save me trouble in the long run... (possible engine damage etc)
Andrew
hi sourcing one from a 617a engine will be a challenge...as this was primarily on a 617a exported engine for the US market fitted to the W116 automatic saloon / estate car..... the cost may be a factor too....I will send you the part No off mine as a guide.......maybe a specialist Bosch pump repair shop could rework the standard pump and calibrate it to suit the turbo you are installing...
Go with Fixwin's timing solution .. getting a 617a injection pump is the final/correct solution but most TB/SST turbos are just probably on a timing fix. This is unlikely to provide that much extra fueling so you are very unlikely to damage the engine.
Getting inside the injector and turning up the fuel is the middle path but requires an EGT and care as it can damage engine.
As to how competant you feel to "tweaking" the timing.. well your call.. but as long as you mark it to start with you can always go back to where you came from with no ill affects.
Hi chaps, I got the G Wagen back yesterday and the turbo doesn't seem to have made much of a difference even after adjusting the timing. If I give it full revs for a second the engine seems to die and theres a puff of greyish smoke. Not really sure what my next step should be. Would I be better taking the injector pump off the donor engine as well as I still feel its not getting enough fuel? Theres no trace of any black smoke when you put your foot down but the engine doesn't seem to sound the same (as what the old engine the turbo came from sounded like) when idling. Considering the size of the turbo I thought it'd have more ooomf! Thanks again.
Andrew
Hi look at the position of the pump on the old engine and compare..you could change the pump from the host engine but mark or measure to make sure you time it correctly.... did you flush the fuel tank.... loads of black gunge (fossil fuel growth) can restrict the fuel flow).. and change the filters (inline and cartridge) grey smoke is an indication of oil being burnt.....could be drawing it in from the valve guide seals if it is starved of diesel at high revs... or the turbo is sucking the flexible air inlet pipe flat. and causing the problem....
:D Hi everyone, I measured the donor engine pump from the engine block and set my pump at the same distance which was closer to the engine rather than further away. One of the pipes was a bit perished and soft hence the smoke at full revs - as Fixwin said its been getting starved of air. I was thinking of a K&N air filter but I suppose it'll be alright as long as I don't go near deep water. She's running much better now and overall I'm very happy so thanks very much to everyone for their help and input :D
Andrew
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Thanks for the info :D (Is this Peter by any chance?) Would I have to remove the engine to change the sump?
It's a TB Turbo thats fitted (well thats what it says on the dial in the dash) I've been in contact with the company but they don't actually refurb them just replace them... Does anyone know where I could get seals and bearings for a turbo if I need them once fitted? Hopefully its the engine thats causing blue smoke for a few moments when the engine is cold and not the turbo itself :roll:
Thanks, Andrew