Vnt-15 installation, slowly but surely.....almost

[Rabbit on Roids]

woah, that turbo is way different. never seen one like that. looks like it would fit in a mk2 or mk3 very well.

[hamradio]

I wish mine was like that, so I could make a little adapter to go in between the turbo and manifold to allow use of an external wastegate.

[ryanp]

looks to be from an afn passat? the Ibiza and polo tdi's have a vnt15 suitable for the mk3/3 engine mounts, the turbo is part of the manifold still but more central to the engine bay.

Ryan

[rabbitman]

looks to be from an afn passat?

Ryan

That's what I ordered the turbo gaskets for was a AFN, strangely enough the bolt holes in the gasket that goes  between turbo and mani don't line up. Easy fix though. The only place I could find 'em was through prothe, I bought three things on ebay at the same time and his gaskets beat the other stuff here by quite a bit.

As for putting a wastegate between turbo and mani, it's about 2-3 inches from the firewall right now.

I'll keep updating as I go, I'm stuck in the shop so I can't put it off anymore, hopefully it'll get done soon.

[rabbitman]

One little thing I did is took the oil pan off, blocked it up at the same angle it is when installed and filled it with 4 quarts of water to see if the turbo oil return is submerged.

The water came to half an inch from the top, I would guess the level goes down some when it's running but unless your really low on oil the return is completely under, especially when accelerating.

[rabbitman]

I made the downpipe yesterday:



Here's some shots of the oil line, what do yall think, a no go?





I decided to make a 2.25 inch downpipe and neck it down into the stock pipe in front of the shifter for now, I don't really wanna sink more money and time into it at the moment. When I get the chance I'm running 2.25 all the way back.

The oil line is 5/16 brake line, think it'll hold up? I'm going to support it with adel clamps to minimize vibrations.

The drain isn't installed yet, pics of it will be up soon.

Any idea's are welcome!

[rabbitman]

Well, I started it today Funny right as it fired I heard a really short squeak and then it went away.

I don't have a hose yet for turbo outlet or turbo inlet. I revved it a bit and the turbo blew some air out so I know it's spinning .

I don't have the vnt controls in yet, I can't wait to drive it so for now I screwed the full closed adjusting screw all the way in and that holds 'em opened all the way.

Oh yeah, I used a 1/2 inch pipe plug to plug the egr port in the exhaust mani, the hole was too big but I think it'll hold. I don't have any pics of it.

Here a shot of the drain:


Does this look like enough clearance?


I primed the oil system with a 13mm socket on a speed handle before start it, I can hit 70 psi cold like this:


I need to run a hose from the red cap visible under the fuel filter to the intake mani on the drivers side:


The downpipe and shifter clearance:


The stupid 2.25 into 1.5 exhaust, hopefully not permanent:

[rabbitman]

I think I decided to use airoquip hose for the turbo inlet with a cone filter, I'd rather use an air box but I don't have one that'll work.

Haven't found anything to use for the turbo to intake mani hose yet.
It will have such stupid bends in it that I need something that won't kink easy.

EDIT: The hose is actually called airoduct, and I'm thinkin' I might swipe the air box off my carbed rabbit for now 'till I can get a real TD one as I need to be able to hook up the breather hose.

Also since I can't find a decent way to support the oil feed line I think I'll get a rubber hose with barb fittings and double clamp it. It should make it bullet proofer.

[rabbitman]

I drove it today .

Ran fine, but didn't have a bit of boost. When I floor it black smoke billows out and I can hear the turbo spool up but the boost gauge didn't even budge.

So I took it back in the shop and could see lots of oil in the clear intake hose, too much for the breather to be the cause.

I took the compressor housing off and the nut that holds the wheel on but I can't get the wheel off.

I did see that when I push the wheel/shaft towards the exhaust side and spin it there's a terrible grinding sound.

So I need to somehow pull the wheel, get the shaft out and find a seal kit then maybe I'll be on the road .

EDIT:   Ok, my mistake, I got the wheel partway off still in the exhaust housing and the grinding was the turbine wheel rubbing the housing


UPDATE:  One possible 'cause of the lack of boost situation is that there were only three bolts holding the turbo into the exhaust housing instead of five, I mustuv over looked it.

[rabbitman]

Well I took the turbo all apart to see if any seals were blown and found out I couldn't tell by looking.

So I'm gonna put it back together with FIVE bolts (instead of three) holding it to the exhaust housing and maaayybee it'll make some boost.

I did a test and blew compressed air into the intake mani and the boost gauge went up so I know it wasn't making boost before.
Even though I could tell by the black smoke and lack of (read "normal") power that it wasn't boosting .

[myke_w]

So I'm gonna put it back together with FIVE bolts (instead of three) holding it to the exhaust housing and maaayybee it'll make some boost.

Having either side mounted off center (not bolted down correctly) could definitely cause the rotating assembly to interfere..   

Also - I'm not sure if this has been mentioned but using a far larger oil line for oiling the turbo could be a problem down the road. In general custom turbo oil supply lines have restrictors, both to maintain high pressure in the motor and not to overload the turbo cartridge. More is not better. If you push oil into the turbo so fast that it can't properly drain, you'll be barfing out the seals, which will be disastrous.

If you don't have one you really need to consider a restricter that reduces the pipe size to that of a the ID of a stock steel line. You also should consider an oil pressure gauge, don't rely on the idiot light.

[rabbitman]

So I'm gonna put it back together with FIVE bolts (instead of three) holding it to the exhaust housing and maaayybee it'll make some boost.

Having either side mounted off center (not bolted down correctly) could definitely cause the rotating assembly to interfere..   

If you don't have one you really need to consider a restricter that reduces the pipe size to that of a the ID of a stock steel line. You also should consider an oil pressure gauge, don't rely on the idiot light.

What I meant by three instead of five bolts is I think it wouldn't seal the exhaust gasses in, so exhaust pressure would bleed off before it could spin the turbo....might be a long shot I guess.

Here you go

Mike, the oil restrictor should only be used on ball bearing style turbos.  On journal bearing turbos, the restriction is the clearance of the journal bearings to the shaft and housing.  The stock VW oil line will flow far more oil than can pass the journal bearing clearance.  Going to a larger line won't affect that.

Andrew

I thought that too, thanks for clearing it up Andrew

BTW, this turbo already has a restrictor built into it, it's deep down in the feed port and I can't fit the back of an 1/8th drill bit into it, so it's even smaller than my oil line ID .

BTW myke_w, your high volume oil pump works great!!!

[rabbitman]

hehe, well I got it to work without the huge oil leaks .

I'm pretty sure the pre-turbine exhaust leaks were the cause of no boost.

First I wired the vanes fully shut and that way I could get about 4 psi if I blipped the fuel at idle.

With the fueling same as it was NA, I took it out and drove it and when I floored it the boost shot up very quickly, up to about 8psi and then the needle jumped up to 13psi so I let off.

Then I completely opened the vanes and took it out and got 2psi max with a little black smoke.

So I turned the fuel way up to the point that it was smoking heavily, I then got 3psi woopy do.

My next test will be to turn the fuel down almost to were it was and close the vanes some, then with some tinkering I should be able to get to my target of 10psi max (for now ).

I have a small seep of oil coming out were I brazed the fitting into the pan . I hate taking the oil pan off.

For some reason I had oil on the outside of the intake mani below the inlet.

Tomorrow I hope to be driving it again.

Next project will be to perfect this setup (read, fix all oil and air leaks), then make a boost controller, which is gonna be tight because of the gasser intake mani.

[rabbitman]

That's what I thought, I only ran it up to about 3600rpm.

I don't see any exhaust leaking under the hood. So I guess that means it must be an intake leak, strangely, with the vanes closed I can hit 4psi @ idle so it seems like a leak would show up easily.

I'll have to experiment tomorrow, I'll update when I find out more. Thanks

[rabbitman]

Well I closed the vanes, set the idle to 1550rpm so I got almost a pound of boost.
Then I crawled under and started spraying everything with soap.
I found that the turbo/exhaust manifold joint is leaking a little bit, just enough to foam the soap.
Also the intake mani is leaking at this joint:



Strangely enough I also have oil leaking out here to .

I'll unbolt it and try to flatted the sealing surface some more and maybe stack another gasket in there.