Need Schwitzer Turbo Info.

[KiwiBacon]

I need as much info as I can find on the following two turbos. They were fitted to International/Komatsu/Navistar/Case DT817 diesel engines in heavy construction machinery.

Schwitzer 4MD-755
Schwitzer 4LF-754

The 4LF appears bigger (i.e. doesn't develop boost as early), I want to know if it's possible to get a smaller turbine housing for it to match or mimick the 4MD.

[2.2 Straight six]

did you host those picutres? the IMG tags don't work.

[J-Mech]

What kind of info do you want. What are you trying to do?

[KiwiBacon]

Originally Posted by 2.2 Straight six

did you host those picutres? the IMG tags don't work.

Oops, should have proof read that one.
No images intended, they were supposed to be links.

[KiwiBacon]

Originally Posted by J-Mech

What kind of info do you want. What are you trying to do?

I'm looking for basic info (wheel sizes, turbine A/R etc) which can help me understand why the 4L turbo is bigger than the 4M.
Then I'm looking for options to make the 4L boost earlier (i.e smaller turbine housing) to lower smoke and save fuel.

Basically the engine we have has a 4L turbo fitted, it doesn't boost soon enough (or produce enough boost), so the engine smokes under load. Looking for options to get it sorted without having to buy another whole turbo.

[tom turbo]

Ok, Schwitzer turbo info. Here are the facts. The 4MD is actually a larger frame turbo than the 4LF. If your 4MD provides higher boost it's because of the turbine housing. The Schwitzer turbos from that era are not rated in A/R, they are rated in Area at the tongue. the 4MD is a hog of a turbo and shouldn't be used on an automotive application. The 4LF is a smaller turbine. However, if the 4 LF is still too big, you probably would be advised to switch to a 4LE. The F wheel is a bit higher flow than the E turbine in that vintage Schwitzer. There will also be many more smaller area ratings of turbine housings to choose from as Schwitzer made many more 4LEs in production than 4LFs. The bearing housing and compressor will all adapt to the 4LE driver (Turbine wheel and turbine housing). Without knowing what your engine application is it's hard to recommend what you really need so this information is thus "in general".
I would recommend that you look into getting the book titled "TURBO". It's brand new on the market and was written by Jay K. Miller, a former Schwitzer turbo engineer and expert. I understand there is an email address in the book that shows how to contact him.
Happy hunting!

[KiwiBacon]

Tom, thank you very much.

This turbo is fitted to a 40 ton bulldozer (International TD25C), it has proved almost impossible to find information on this turbo.
The engine was available in several different power ratings and we suspect it has the turbo from the higher rated engine.
Uprating the engine to suit is not really an option as we'd like to preserve the driveline.

Is this the book you mentioned?
http://www.racecar-engineering.com/r...-k-miller.html

Do you know of a good source for these turbo parts? Location doesn't matter much as long as the price is reasonable and they are willing to ship internationally.

[tom turbo]

Yes that's the book. Personally speaking, I really liked the way that book was laid out and it covered some rather difficult concepts in a way that made them easy to understand. It's pretty well written.

Anyway, I could recommend a couple of options for you. One is to log onto www.turbodriven.com. That's the Borg Warner website (They bought Schwitzer 10 years ago) I would tend to recommend you contact a distributor located in either New York, or in Florida. Those distributors are typically more accustom to exporting than the typical distributor in the U.S. heartland. That said however, Columbus Diesel Supply in Columbus, Ohio is kind of the premier home of large bore diesel performance turbos due to their prominance in advanced tractor pulling. One year they were even voted manufacturer of the year by the puller magazine. (They are even shown in that book)
You can reach them at www.columbusdieselsupply.com. Ask for Mark Massey, he really knows his stuff.
One last thought. The 4MD and many of the 4LE/F series turbos are going to have straight radial element compressors which means a very narrow flow range. Further, the compressor and turbine efficiencies are going to be way below what is otherwise available. While I don't know exactly what you're doing, and it's none of my business, but I know many times people get a cheap turbo off of something older and want to use it. By the time you add-up that cost, plus the very expensive older model parts to tweak the trim for flow matching (if it can even be done with that model) the good money is being spent after older technology. For my money I would rather apply a later model Garrett GT that has much higher Aerodynamic efficiencies, has a BCI type compressor for extended flow range, inducer blled, and uses a ball bearing for further machine efficiency and response time. These things are also well laid out in that book for you along with many later model compressor maps and how to match them to your project. Columbus Diesel can help with all that too I'm pretty sure.

I hope this all helps you to some degree.
Best wishes & Happy hunting.
TT

[KiwiBacon]

Thanks again.

The goal here is simply to get the old dozer running as it should. The current turbo is a mismatch and until now I haven't been able to find anyone who knew anything about these turbos.

The plan is to get it running properly for the least cost. A replacement turbine wheel and housing fits that bill nicely.