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Discussion Starter #1
Hi guys my first post on this forum, I recently obtained a Skyline Gt R32, I have no history with regards to this car/mods etc as it was imported from Japan to South Africa. Car looks fairly stock, 2 twin turbo 4wd but with a custom intake box

Problem is that the car is not boosting, car is driveable but very lazy as there is no boost obviously. Car is smooth and gets up the rev range but gradually.

I have no clue where to start fault finding on this car as I come from the VW stable and this is my first turbo car.

From what i have read or picked up so far, its either my turbos are stuffed or the actuator arm is off or seized.

Please assist me with regards to checking these, its a learning experience for me and I dont want to start opening and changing stuff for nothing with no reasoning behind it.
:thumbsup:
 

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Hi there,

Are you getting absolutely zero boost? Are you going off of the stock boost gauge to come to this conclusion?

I'd say you need to check for any boost leaks - all the way from turbos to inlet plenum, all the intercooler connections/pipes etc. making sure everything is tight and there are no splits.

If all good, check the wastegates aren't stuck open (and are connected properly). If they are ok and you're still getting no boost, I'd check to see if the turbos actually spin and aren't seized or anything.
 

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Discussion Starter #3
Feels like absolutely no boost
I did check for leaks but don't seems to find any, is there a specific way to test for boost leaks
Where is the wastegate situated and what does it look like and how would I check if it's stuck open
 

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Check out this pic (the front of the car would be to the left, with the bulkhead/windscreen on the right). It won't be this obvious when you look in the engine bay as a load of plumbing and bits and pieces has been removed here.

See the two metal rods going from the cylinder-like bits on the left to the metal flap on the right... The cylinders are pressurised by boost and press the rods to the right hand side, swinging the flap, which opens the wastegate. They are sprung but if you grab the rod and push it to the right, you should be able to open the wastegate manually (and it should spring back shut). If yours are stuck to the right and/or the rod is loose/unsprung, they aren't working.

(Obviously also check the rods are actually connected and the pressure lines are connected).
 

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Another pic here (not this is non-standard so not exactly the same!):


See the "taped off"/"blanked off" bits pointing upwards out of the turbos - these will have a common pipe bolted to them that takes the pressurised air from each turbo, joins them into one "stream"... like this:

The bit in question has the "twin turbo" badge on it... it's bolted to the front/leftmost turbo and connected by a soft pipe to another piece that's bolted to the rear/rightmost turbo - check this soft pipe is connected properly with no rips or tears. If necessary, get someone to rev the engine and feel around it for leaks/airflow that shouldn't be there.

Now, on from that "twin turbo" pipe towards the front of the car, the air flows have been combined from both turbos and are carried to the intercooler - you can see the next soft pipe there in the pic... Check this pipe its connection to the twin turbo pipe, and its connection to the intercooler, rips and tears, rev the engine trick engine, etc.

On the other side of the intercooler is another soft pipe, which you can see here:

coming up on the left hand side to the throttle plenum. Check connections both ends are secure, no rips tears, engine rev whilst feeling around again etc.

You can also try spraying WD40 around potential leak sites at idle and seeing if the revs rise, it may work, but don't go too mad with it.
 

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If the above fails to help, the next step (I would think - someone chime in if I'm wrong/there's a better idea), would be to take off the pipes going from the airbox/aftermarket air filters to the turbos, get your hand/finger inside the compressor housings and spin the compressors by hand to see if they spin smoothly or are gritty/grinding/seized/have massive play.
 

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Another thing - check the pipework when you take it off, both from air filter side and downwind of the turbos and see if there's a ton load of oil in there (there'll be some, just shouldn't be loads of it). If there is, could be turbo failure, although having said that - are you getting loads of blue smoke when revving the engine, or is everything normal?
 

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Discussion Starter #8
Wow, you have really helpful kind sir, I understand what you saying and will conduct those tests.
There was some oil when I removed one of the boost pipes but not alot, if you rub your finger or the inside of the pipe, there will be some oil on your finger basically.
Also the car didn't smoke from what I noticed nothing out of the ordinary.
 

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Good idea. Probably the easiest way is to just unbolt the cat from the downpipe and run it with only the downpipe on, seeing if you get the same results.
 

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Discussion Starter #12
cool, thanks guys, its pissing rain here this side of the world, so cant do much this weekend but cant wait to start tinkering with this car and have it properly sorted.
Will report back once I did some proper tests as advised so far.
 

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Also check all the vac hoses. They will probably be getting perished by now and my old one had a split at the back of the fuel rail where the vac hose goes onto a nipple there which caused me all sorts of headaches :)
 

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Discussion Starter #14
cool, will check the vacuum pipes as well but didnt hear any vacuum leak sounds as i did suspect that as well.

Also which would be the easiest way to check the wastegate arms, cant see remember seeing much from the top the last time I looked there.

Would it be easier from under the car ?
 

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Discussion Starter #15
some feed back
I opened some of the boost pipes only to find quite abit of oil inside them, what does this mean ?
The last I drove this car was about 3 months ago and it didnt smoke then, neither did it boost but now it seems to be smoking when i started it up.
I stripped most of the boost pipes and removed the intercooler as well as I want to send it for cleaning because Im sure it must be full of oil as well by now, aslo managed to turn the turbo impeller with my finger, no grinding or grating noises in there, they didnt really spin either as i had to push it each time with my finger to get any movement out of them.
Also with regards to the wastegate arm, how hard is it to move them back and forth to open and close the valve because i battled to get any movement from them using my fingers
 

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Discussion Starter #16 (Edited)
Guys any advice on opening the turbos please, I started stripping but finding it difficult to get to most of the bolts inorder to open the turbo.
Should i open the exhaust mani direct from the head, then undo down pipe and remove.....this seems abit challenging at the moment as i cannot get to the bottom exhaust mani nuts.
Other option is to open the turbo from the exhaust mani housing and remove.
Just wondering if there is another method cause at the moment I'm just opening everything thats coming in my way to make space
 

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From the compressor inlet you should be able to turn the turbos freely with no restance. If there is any restance there's a problem. You can also check for excess movement in the impeller, up and down, side to side. There should be minimal/almost no movemvement with a little movement front to back only. If there is a lot of oil in the pipework it would be due to play here in the turbo been worn and oil getting past the seals.

Sorry I can't help with removing the turbos.
 

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Sorry took my eye off this thread for the last few days.

As above really.
- It should be easy to turn. Or at the very least, it should be easy to turn once you have it turning (once you've freed it up, it should spin easily.
- Check the movement as described above
- Lots of oil isn't good - could be that the turbos have had it :(

With removing the turbos, check out RB26 Stock Turbo Removal - Nissan Skyline Owners U.S.A. - Forum
 

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And the wastegate arm - they are quite hard to move, you'll need to grip the bar really well in order to get enough leverage if it's possible. However, if they are in the closed position, as with the previous pics, it shouldn't (in theory) be that the wastegates are stuck open.
 
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