Garrett GT4702 map

[maconques]

First a quick hello and thank you too all you guys here. I'm a junior in Mechanical Engineering and was having trouble coming up with a worth while senior project...till I can across this site lol. The amount of technical prowess displayed in the machines on this site beggars belief. I am continually in awe of what can be accomplished with some simple machine tools

Now to the question. A local company kindly donated a Garrett GT4702 turbocharger off what I believe to be a Detroit Diesel S60 engine. I have searched for a compressor map without luck so I was hoping someone here could steer me in the right direction.

Thanks for the time
Matt

[Johansson]

Hi and welcome to the forum!

This sounds like an interesting senior project, it will most likely steal the show at your school and the guys who made WoW gaming chairs, toe nail cutting machines and belly button scratchers will get very upset. ;D

I have no idea where to find a GT47 comp map though, but hopefully someone can help you out.

Cheers, and remember that stubborn people don´t need CNC.

/Anders

[racket]

Hi Matt

Measure the wheel sizes and scroll A/Rs and go to www.turbobygarrett.com/turbobygarrett/turbocharger#performance-tab to compare

Cheers
John

[maconques]

Hi Anders and John

anders: Maybe we might opt for a hybrid project with another group,"Gas Turbine powered toenail clipping machine"...well on second thought maybe not lol. And I've seen what you can do with manual machines, I would be scared to see what you could create with some CNC machines lol.

john: Thanks so much for the link, it proved to be massively informative. Ill break the turbo open and get a hard measurement on the wheels and see what I can find. There's so much to learn about these turbos, they are marvels in their own right!

[Johansson]

Mar 30, 2012 8:06:05 GMT -5 maconques said:

anders: Maybe we might opt for a hybrid project with another group,"Gas Turbine powered toenail clipping machine"...well on second thought maybe not lol. And I've seen what you can do with manual machines, I would be scared to see what you could create with some CNC machines lol.

Scared is probably the appropriate word for when I try to run a CNC machine, I have trouble getting the pocket calculator to work so any attempt to start a CNC mill would most likely end in disaster... ;D

[turbochris]

I'm good at getting CNC machines to throw parts and tools all over the shop.

[racket]

Hi Matt

Theres considerable mixing of parts within "families" of turbos , but if you measure the wheels you can get the info , even if its from two different turbos .

Let us know the sizes and we'll see what we can find :-)

Cheers
John

[maconques]

Hi John

I took possession of the turbo and cracked her open. Sadly I chipped the compressor wheel in the process. The measurements were 80mm inducer and 108mm on the exducer, which places the turbo as a GT4708 from the link you gave me. Needless to say I'm thoroughly disgusted with myself for ruining the compressor, but at least the turbine side is fine. Maybe that was God's way of telling me I need to wait for a GT6041 . In any case I'm back on the hunt for another suitable turbo, such is life I guess lol.

P.S. Thank you all for the welcomes and informative replies...and patience of course. I've already learned from yall and I've only read two threads lol.

Matt

[racket]

Hi Matt

Just get another compressor wheel and screw her (left hand thread) , and/or simply have the rotor rebalanced with the chipped wheel ..................LOL, no point throwing away a turbo just because of a chip :-)

What were the turbine wheel sizes?

Cheers
John

[maconques]

Hi John

Knowing that they can be rebalanced with a chip is sweet relief. I have a VT-50 that I gave up on because of a chip which I might resurrect then lol. The turbine wheels measurements are:
Inducer--93mm
Exducer--84mm

I am actually just coming back from separating the turbine scroll, it took more persuasion than the compressor end. But thankfully I learned from my mishap on the comp and was able to do the deed without any colateral damage. I did find that the turbine bearing surface of the turbine shaft looked as though it had heat damage. It seemed to have a bluish tint, I took this discoloration as bearing failure but I make a habit of being wrong sometimes. I will upload some pics tomorrow probably as it is 11:50 here and the turbo is at the shop.

Thanks
Matt

[racket]

Hi Matt

That turbine wheel is probably a tad smaller than ideal but certainly usable .................the bluish tint on the shaft journal is heat soakback .....................LOL, us DIY'ers have a lot of that on our turbine wheel shafts ;-) ................nothing to worry about , some of mine have ended up being a dark purple for an inch along the shaft . .

The chip can be blended out if its not too big , considering the short usage times of our engines its unlikely that a crack will develop from the chip over that short time frame , the worse that can happen is a chunk of blade comes off and goes through the engine rendering the turbo unusable , but thats what it will be anyway if you don't use it .

Looking forward to the pics , we'll be able to better assess the parts :-)

Cheers
John

[maconques]

Hi John

I need some assistance uploading photos. I applied for and received a api key, but I don't know what to do with said key lol. I took some pictures of the wheels and shaft tonight and I was hoping to share them with the board.

Regards
Matt

[Johansson]

Get a Photobucket account, before I got mine I used to upload pics on the different forum servers but it is much better to have your own place where you keep them.

Pics are less prone to disappearing after server crashes that way, image size is not restricted to matchbox size and you can use the same uploaded pic in lots of different forums/whatever.