Hi,

I have a 3306 serial no. 66D01651 that I am doing some major work to. I noticed there was oil in the inlet manifold. I removed the turbo part no. 8S-8039 and left it lying with the compressor side down for a month or so whilst I was working on the engine and some oil came out of the turbo where the it normally connects to the manifold.

I am not a mechanic but don't mind having a go. Is the turbo disassembly and repair do able or is it a specialised job? I noticed the nut holding the impeller on looks like it needs a special tool. I did read in the service manual that to put the impeller on it first has to be heated to 350 F. There is no mention of how to get it off nor any instructions at all about rebuilding the turbo.

Is there any service information available?

On YouTube it doesn't look that difficult but can anyone offer me their opinion?

Thanks Ian

That is one thing I would send out. First, I wouldn't neccesarily know what parts were usable, as nd what needed replacement. Teardown and reassembly might need special tools or techniques. Balancing? That should be checked as well. How about checking for cracked wheels?
You might have a very generic turbo that could be readily. replaced, but the farms ammonia compressor engine was natural gas so a new turbo was nonexistent and we didn't have time to experiment. You might check around for information and take it on.

one option is getting a drop-in core and all you have to do is change the outside housing and clock them right fairly easy.

Like mog said get an exchange cartridge, just remove the housings. A reliable turbo shop or your Cat dealer should have it.

Service information and specifications are available. Does require a 8S9944 turbine holder and 9S6343 fixture assembly. Not only does it hold the turbine but positions the compressor end for heating in oil to 350* for both removal and installation. Unless your really in to it the cartridge exchange is the way to go.

Thanks to all, I will send it out to a repair shop.

Hi Team,
also be aware that running with an excessively clogged air cleaner--inlet air restriction--will cause oil to be drawn thru the compressor wheel end piston ring oil seal on the shaft.
Diesel engines usually have little inlet restriction from the likes of a throttle butterfly as petrol/gas engines use and so do not have a positive oil seal at the compressor end of the rotating assembly.

The advice to go with an Exchange Cartridge Assembly is the only way to go.

Without specialised training and knowledge a DIY is likely to fail--these things can spin upwards of 70,000 RPM and need the sort of tooling OM has described above as well as marking and refitting the compressor wheel back in exactly the same orientation or else the rotating assembly dynamic balance can be lost and at 70,00 + RPM you can see it may not end well.

We often used to get G Series Grader turbo's in to the Dealer after the engines had been stalled and then run backwards and so had clogged the inner of the air cleaner element or safety element, if fitted, with soot, only to leak oil into the manifolds again when an exchange or reco. unit was refitted and they had failed to heed our advice to check the air cleaner elements.

To overcome this Cat modified the Injection Pump cam profiles so fuel was not injected where the engine could run if turned backwards.

Cheers,
Eddie B.