An Amateur's Turbocharger repair

[JR IN JAX]

My Honda PWC's turbo ate the inconel turbine wheel after 500 hours. A replacement turbo was $2,500.00 but is no longer available. There are no shops that rebuild them due to their ceramic ball bearing construction since they spin at 200,000 RPM [no misprint].

I read everything I could on turbos and talked with some Black-Belt Techs and decided to buy some junk turbos and try it myself. The wheel and shaft are one solid piece so you have to pull/replace the shaft to change wheels. The ceramic ball bearings are loose with open sided races that fall apart when the shaft is pulled on the turbine side and when the cartridge assembly is opened on the compressor side. I have rebuilt two strokes with loose needles before but this was harder by a factor of ten.

The technology inside them is amazing. The ball bearing turbos only use a trickle of oil for lubrication and have no oil seals on the shafts. The trickle of lube oil gravity drains back to the engine's oil sump. They do have a compression ring type seal that keeps boost/exhaust pressure out of the turbo's core. The turbine wheel is over 1000* during operation. The Compressor wheel weighs almost nothing and is not keyed to the shaft but somehow it does not spin [on the shaft] even with the rapid accel/decel as the throttle is opened/shut.

It took me hours with machinist tweezers and a magnifying glass to figure out how to load the bearings and then install them into the cartidge assembly with a new shaft. After several failures/removals/reinstalls, I have boost again.

I am glad I don't repair ball bearing turbos for a living, I'd rather pump septic tanks.

I hope to take it out on the river tomorrow to see if the ceramic bearings hold up.

I know this isn't a boat engine but thought it might be interesting anyway.

[STV_Keith]

Might want to give a call to Turbonetics (http://www.turboneticsinc.com) in CA. They offer a line of ceramic BB turbos and routinely work on them. They may even offer a replacement turbo for your application. Would be nice to know for the next time. :)

[JR IN JAX]

Might want to give a call to Turbonetics (http://www.turboneticsinc.com) in CA. They offer a line of ceramic BB turbos and routinely work on them. They may even offer a replacement turbo for your application. Would be nice to know for the next time. :)Keith,
I and the other Honda Turbo owners have talked to every known Turbo shop and they all tell us that IHI will not sell the rebuild parts [bearings/cartridges, shafts or compressor wheels.
Blounch, Turbonetics and Majestic all initially thought they could rebuild them but could not once they were sent one. There is not much they can do without parts. The new Honda 15Xs use a different turbo.
Hopefully there will be enough Hondas that are parted out to keep our skis going since other than the turbos and blocks freezing up north, they are rock solid dependable.

[jtaj77]

Do you have any pics? My sister has two of those 1200 turbo skis. One of them is pouring oil into the hull right now. Have you had that problem?

[STV_Keith]

JR, did Turbonetics offer a bolt-in replacement unit for the stock IHI unit? I have to imagine something is available that would retrofit in it's place and be rebuildable.

[JR IN JAX]

Do you have any pics? My sister has two of those 1200 turbo skis. One of them is pouring oil into the hull right now. Have you had that problem?
The oil leak problem is usually one of the oils lines running under the engine rusting through. I believe you have to pull the engine to change it. They also have had some of the Oil Cooler housings crack from freeze damage too.
She can get some good info on PWCTODAY.COM. in the Honda forum.

[JR IN JAX]

JR, did Turbonetics offer a bolt-in replacement unit for the stock IHI unit? I have to imagine something is available that would retrofit in it's place and be rebuildable.
Keith,
Some of the racers have retrofitted theirs to larger turbos but the price is very steep and requires moving most of the exhaust plumbing and retrofitting all of the oil lines. I took mine out today and got carried away, overboosting to 21 PSI. It was a rocket but finally snapped off the compressor shaft, either from unbalance or overspeeding.

[jtaj77]

I took mine out today and got carried away, overboosting to 21 PSI.
What kind of boost should they make?

[STV_Keith]

What is the bolt flange type of the turbo? Do you have a pic? What model ski is it exactly?

[JR IN JAX]

What kind of boost should they make?The stock boost is 13PSI on 93 octane with an electronic wastegate actuator. At 13 PSI the turbos is spinning over 150K RPM and at 21 PSI, who knows. I should not have done it but it was soooo fast.

[JR IN JAX]

What is the bolt flange type of the turbo? Do you have a pic? What model ski is it exactly?
It is a water cooled housing on my Honda Turbo F12X and it fits into a really crowded hole inside the engine bay. It is almost impossible to just get to the oil lines to unbolt them. I have never had the complete exhaust turbine housing out of it. There have been retrofits but I would guess that they cost as much as a new 'ski. I have a double-sized aftermarket intercooler on mine already.
I hate to spend too much more on retrofits since I am intending on buying a Honda 15X turbo soon that will make 300+ HP with just an ECU/intercooler change and still get 7 MPG like mine does.

[STV_Keith]

Have you ever considered putting a wideband O2 sensor on it to see just how much is left on the table? I believe the guys in our PowerSports division already played with a custom Power Commander for the F12x...but you'd want to know how lean or rich it is before you start adjusting the fueling and boost.

[JR IN JAX]

There are several aftermarket ECUs, some with closed loop [wideband o2] available now for racing. I would get one but I still jump waves with mine and they seem to be more fragile than the OEM ECUs. Autotronics is one of them. The ECUs kits come with a built in custom map and the software to modify it.

Before you can do too much more boost and RPM, you need to modify the valve springs. Mine already ate a valve back when it was new and a 15X was leading the Catalina offshore race when he leaped out of the water and hit 8.8K and ate a valve. The 15Xs look like they hold a lot of promise winning several big races lately.

[STV_Keith]

What do the aftermarket ECU's cost? With closed loop O2?

[merctech5591]

i have to agree with the reliability of the honda pwc.. i had an 04 with 160 hr's and never gave me a lick of trouble. oil, oil filter and a little grease and they were good to go. on the other hand my neighbor has a kawi 4storke and his lived in the shop. 2 motor's and a throttle body.. i use to rub it in all the time.. "should of bought a honda"..

our local pd department has two honda f15 turbo 3 seaters they are in for a 200 hr service with no problems yet.. by the end of next year they should have close to 1000 hr's on them.

[JR IN JAX]

i have to agree with the reliability of the honda pwc.. i had an 04 with 160 hr's and never gave me a lick of trouble. oil, oil filter and a little grease and they were good to go. on the other hand my neighbor has a kawi 4storke and his lived in the shop. 2 motor's and a throttle body.. i use to rub it in all the time.. "should of bought a honda"..

our local pd department has two honda f15 turbo 3 seaters they are in for a 200 hr service with no problems yet.. by the end of next year they should have close to 1000 hr's on them.There is a guy that owns a PWC rental shop in Maui and most of his have over 1500 hours on the same engines. His last fleet was Yamahas and they were blowing oil out at 400 hours. Both my last Yamahas [2-stoke GP1200s] had several rebuilds by the time they reached 400 hours.

[JR IN JAX]

What do the aftermarket ECU's cost? With closed loop O2?
Keith,
This is one of the kits for $1750.00, I don't think it includes the O2 sensor but is set up for it. The water jacket/water entrained exhaust make it hard to locate a sensor.
http://macsboost.com/

He also sells intercoolers and other stuff. He is an Engineer for a big NASCAR team.

[STV_Keith]

Is the wastegate electronically controlled? I bet our CMD device could do the boost/fuel tuning on that engine...and it retails for $449

[JR IN JAX]

Is the wastegate electronically controlled? I bet our CMD device could do the boost/fuel tuning on that engine...and it retails for $449The waste gate uses a Pulse Width Modulated Solenoid [Dithering solenoid] to increase the pressure between a restrictor-pill and the pneumatic wastegate actuator.

Some of the biggest problems with developing aftermarket ECUs is: Making waterproof connectors, heat and vibration, waterproof housing for the ECU, coil duty cycle, injector duty cycle and the weird signal from the crank-angle sensor.

[thewombis]

Its to bad the "personal watercraft" has become large enough to house a 4cyl 4 stroke. :( Back in the days of the big bore 951cc 130hp 2 strokes...those are where its at!:D

[STV_Keith]

The waste gate uses a Pulse Width Modulated Solenoid [Dithering solenoid] to increase the pressure between a restrictor-pill and the pneumatic wastegate actuator.

Some of the biggest problems with developing aftermarket ECUs is: Making waterproof connectors, heat and vibration, waterproof housing for the ECU, coil duty cycle, injector duty cycle and the weird signal from the crank-angle sensor.

OK, so the boost control uses the same method as the cars we already control. Great! The connectors we use are factory supplied or molded after factory, so once we see them, we can source or create them. Our main harness is the waterproof Delphi connector used on HD motorcycles for their ECU connector. Sounds like it's a no-brainer. Just need to get one in here to o-scope the crank signal, boost solenoid frequency, etc. :)

[JR IN JAX]

Keith,
You can go on the Honda Forums at http://www.pwctoday.com/f18/ and http://greenhulk.net/forums/forumdisplay.php?f=77
You can find a Vegas Honda owner on them who would be able to help.
This is someone who is also working on them. http://www.pwctoday.com/f18/