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Replaced turbo. Now oil smells like gas & smokey exhaust...?

Y

yorkadam

Member
Joined
Dec 14, 2012
Location
Lansing, MI
Replaced the blown turbo on my 83' 245 B21FT. I also put in a 90+ manifold because the old one was cracked. Since the 90+ doesn't have an oxygen sensor bung I relocated a heated o2 sensor to the down pipe and wired it in. Also replaced a lot of vacuum lines if they looked worn. Mostly associated with the turbo but I also replaced the ones to the throttle body.

The problem: Smoke out of my tailpipe...but worse but worse this time! I also checked the oil - it smelled of gas but no bubbles or frothing. No coolant contamination.

So the question is - did I cause the gas in the oil by how I lubricated the turbo? (see below) Or is there something else wrong? I had a compression and leak down test performed. My car had good numbers well within range. My initial guess was maybe a head gasket being blown but that would be coolant and oil combination, not gas, right?

Procedure to lubricate turbo prior to starting:
Disconnected the ignition coil (-) 1 terminal and turned the engine over for two periods of 15 seconds. Checked for any major coolant or oil leaks. Reconnected (-) 1 on the coil and tried starting. Would turn over once, but then die. I kept trying several times until I saw the inter-cooler throttle body hose disconnected...!@#$!. Once reconnected it started right away. I let it run for a minute then inspected it for leaks. Started it back up and let it run for a few minutes. The only noticeable problem was a leak at the manifold turbo flange. Easily solved with a gasket it would only cause it to run rich, not smoke heavily... Checked oil and it smelled of gas. Checked o2 sensor and it was super sooty.
 
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I don't think the b21ft has a FPR - I have a CPR (control pressure regulator)...

Catalytic converter is still there and intact. I merely put an oxygen sensor in the down pipe. Again this shouldn't matter since I can run the car sans o2 sensor. It'll just suck for the air fuel mixture being accurate.

Does vacuum hose size matter? I used the ipd vacuum hose kit and replaced what i removed with the closest size match: http://www.ipdusa.com/products/5592/106943-heavy-duty-vacuum-emission-hose-kit
 
apachechef said:
Lesson to not replace too many things at once. check your vacuum lines
Click to expand...

Not exactly helpful...Also I plumbed everything as it was...which isn't saying the last owner was right!

I did notice two oddities:
1) There is no overpressure switch under the dash, just runs straight to the VDO boost gauge.
2) The CBV on the td04-12b has also been plumbed into the firewall pressure switch so it's got two 'T's off of it. First connects to the CBV on the turbo, second to the manifold vacuum port, then it goes into the firewall.

Also to note: I calibrated my turbo wastegate actuator to the 7-8psi recommended for an IC equipped B21Ft.

So while I look at all of the lines... Should I just delete the CBV from the pressure switch?
Where should the CBV vacuum line be routed in the future?
Overpressure switch is MIA - normal?
 
Possible error: I removed only the ECU (-) 1 ignition coil spade assuming the procedure meant just delete the spark. Looking around I found out what the other (-)1 terminal spade goes to.... drum roll: fuel pump relay, which does not talk to the ECU directly it seems.

So if I'm cranking on the engine it's not sending spark because terminal 16 on the ECU is disconnected...but still sending fuel because terminal 31b on the fuel pump relay is hooked up.

Fuel - spark + cranking = gas in oil?
 
changed oil - got it running and the exhaust went from normal slightly cloudy like water vapor -> slightly sooty -> smoke machine with a lot of water coming out. So I stopped. o2 sensor was a lot less sooty this time bu the oil was worse.

drained oil and it had a little frothing and white stuff in it. Still smelled of gas again, but hard to say if it was prior contamination, also the oil filler cap on the cam cover had a milky substance on it....

so I'm going to guess two things here - help me figure this out...

1) head gasket? but that doesn't explain the gas smell
2) turbo is some how mixing the two fluids?
3) ???
 
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In the event I need a new head because it's cracked or warped badly - how do I tell if it's a BCP or SCP head?

Center of the head:
1000106
IMP

Made in 82' noted on the left...but nothing about BCP I could discern.
 
If it was just gas in the oil, I'd say you were running too rich or your valves needed work. But now the frothy white stuff is leading me towards the same head gasket/cracked head diagnosis.

Before worrying about SCP vs BCP, you should focus on getting a diagnosis of head gasket vs. cracked head first (one will obviously be a lot cheaper than the other parts-wise). Then find the correct head for your KJet system if it needs to be replaced. You need a 398 for it.

And I concur with the "don't change too many things at once approach". It's very dangerous, particularly with cars like these where the POs likely took "liberties" to keep it running.
 
Forgot about the 160 heads. I thought the B21FTs should've had the 398 by '83. But, you could use either one.

I also heard tell that there are a few 398 and 160 SCP heads, but I have no idea how you'd tell that if the head was still on the car (like in a junkyard).

Put a post in the Wanted section if you're looking for one, I'm sure someone's got something for you.
 
I thought of that, too, maybe the center cartridge of the turbo is cracked/bad. But I think the issue was there before the swap (if I read the OP correctly). What are the chances of getting two turbos with bad center sections?

But this wouldn't account for the fuel in the oil, which may or may not be just a overly rich fuel condition and not related to the head at all.

Or, it could all be related to a bad head.

Gotta love working on cars :roll:
 
Dakar09 said:
What are the chances of getting two turbos with bad center sections?
Click to expand...

Well, certainly possible, if quality of turbos unknown.

Who rebuilt turbo or is it reman, or new, or new "china-bay" special??

Sorry, but turbo rebuilding is far more serious work than many seem to understand. I had leaky rebuild from the one and only Cherry Turbos!

The turbo may simply be fubared before it was installed, and never had a chance...

Also, was fresh oil put in before starting turbo? Dirty oil will kill any new turbo...
 
Dakar09 said:
I thought of that, too, maybe the center cartridge of the turbo is cracked/bad. But I think the issue was there before the swap (if I read the OP correctly). What are the chances of getting two turbos with bad center sections?

But this wouldn't account for the fuel in the oil, which may or may not be just a overly rich fuel condition and not related to the head at all.

Or, it could all be related to a bad head.

Gotta love working on cars :roll:
Click to expand...

I read it as milkshake happened post swap, first turbo just "blown"
yeah, great hobby;-)
 
td04h-12b has oil and water lines unlike the stock turbo which was originally just oil.

The turbo is a slightly used remann from someones scraped project. Far less shaft play and no obvious leaks. Hard to say if it's to blame, but I'd guess unlikely given the oil, coolant, and gas combination. Not to mention the lack of oil from the tail pipe (original blown turbo symptom). I'm now getting white smoke with a lot of water. Doesn't strike me as an indicator of a bad turbo.

What I think shouldn't be over looked:
Cranking the engine with fuel and no spark (an accident I now appreciate) was bad, but should NOT have contaminated the oil. I'd guess given that scenario the issue is in the head itself or the gasket. Possibly putting on a new / flat manifold and torquing it down was the last straw and perhaps my last manifold appearing to be warped was just my prospective being wrong: it was the head?

There is also was also some visible weeping at the back corner of the head, exhaust side. Hard to tell what fluid it is, but looks mostly like coolant. Originally at first glance I had assumed it was the valve cover and possibly oil...an optimistic guess.
 
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