Wires' 12a Turbo

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Wires
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Re: Wires' 12a Turbo

Post by Wires »

Well after a couple of successful runs on Wednesday night, I thought all was well.

Decided to take it out yesterday, checked the plugs before hand and they looked good.

About a mile down the road, coughing and spluttering once again. Pulled over, checked the plugs and they were fouled.

Put in the brand new spares to get me home, but it was immediately spluttering and not happy. Managed to limp it back on the smallest amount of throttle, anymore and it would just start to buck and struggle.

So I'm thinking of draining and dropping the tank to give it a full inspection. perhaps there is crud in there that is just making a return once it's sat for a bit. Will have a look at the rear fuel filter as well, thats clear so might shed some initial light.

Trying to stay positive!
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Re: Wires' 12a Turbo

Post by Wires »

update:

Drained the tank, nothing but perfectly fine fuel, so I'm starting to think that the issue isn't from the tank. Changed out the rear fuel filter again, just in case and went to drop the tank anyway, but a one of the straps rear bolt nuts sheared off on the other side, so it was just spinning, sigh.
Wondering if I can drop it from the forward side strap bolts in stead?

I seem to be getting spark and I can hear both the fuel pumps doing their thing.
I hooked up a piston compression checker, as I cant start it there was no chance of using it at operating temperature, so I expect the readings to be low, but the pulses were all equal and seemed similar across both leading plugs. It was getting well over 30psi on each pulse

the engine as normal, was spitting out this though:
Image


I'm super reluctant to throw more new plugs at it as it's just destroying them: NGK BUR9EQ and BR8EQ's for ref.

Plenty of smoke coming out of the exhaust when its trying to start, no doubt burning that oil. I'm starting to think a seal has gone?

Tonight I'm going to pull a fuel hose as near to the injectors as possible to double check the flow is getting through.

What about some seafoam, maybe that could clear out any issues, it could have a lot of carbon build up from being idled for so many years. Saying that, I need the thing to start first!

Any advice appreciated.
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Re: Wires' 12a Turbo

Post by TOOL »

Check the turbo.
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Re: Wires' 12a Turbo

Post by Wires »

I wonder if the air filter is too restrictive at idle/low rpm and is pulling oil from the turbo. I shall investigate.
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Re: Wires' 12a Turbo

Post by Wires »

So after smelling fuel on the oil and seeing how much was coming out of the plug holes when cranking it, I asked Mick Hurley from HME Rotary to come down and take a look, already knowing that it probably needs a rebuild in the back of my head. Sure enough he agrees, so the engine is coming out.

It is what it is, at least I can get more knowledge from taking it all apart and tidy the engine bay up while I'm at it.

Thanks for all the help and advice so far, I'm sure I'll need more of it in due course.

Time to go photograph everything!
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Re: Wires' 12a Turbo

Post by TOOL »

Fuel in the oil happens with ported rotaries. That's one of the reasons we change the oil regularly.

Be sure it's not the turbo dumping oil into the intake before you rebuild it.

Get him to do a proper comp test on it too before you pull it out.

Good luck.
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Re: Wires' 12a Turbo

Post by gt_james »

Why does he think it needs a rebuild?
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Re: Wires' 12a Turbo

Post by Wires »

We turned it over with the plugs out and the amount of oil coming out was pretty impressive so he reckons the oil control rings have gone. The turbo wasn't even connected and there was only a tiny amount of dirt in the intake when I took it off.

He seems to know his stuff and has been working on rotaries pretty much his whole life.
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Re: Wires' 12a Turbo

Post by ian65 »

Hurley was the man back in the day... I'd be happy to take his advice... I'd still check the turbo seals while it's off the car though.

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Re: Wires' 12a Turbo

Post by Wires »

Absolutely, I'll get it recommissioned. Gonna use the opportunity to change the water pump seeing as the old rad was full of crap. Any other suggestions whilst everything is out?
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