I'm always trying to think of ways to make the accessory drive on my engine better. I don't have a lot of room on the sides of the engine for extra things like if I wanted to go back to a mechanical power steering pump, but I have a TON of room in front of the engine. I stumbled across one of these a while back while looking through a Pick N Pull and had to get one.




It's the accessory pack from a 90's Toyota Previa mini van. They're pretty cool (for a mini van) in that the engine is under the seats, but the accessories are all at the front driven by a driveshaft from the front of the engine. Many were all wheel drive, and supercharged. This one has the alternator, power steering pump, and supercharger. I left the AC pump at the yard, because I don't need it, and didn't want to pay for it. The supercharger is a Toyota SC14, which is 1.4L, and makes 6PSI with the 2.4L gas mini van engine.

My plan is to run the water pump off of the original engine pulley, which is already machined for a harmonic damper, so an adapter for this will be really easy. I'll probably have to cut off the splines on the end of the crank, and maybe do a little work to the drive side of the accessory pack, but otherwise it should attach pretty simply with plates to the sides of the engine.

 

That's a great idea!

 

Edit

 

Mn_p_25.html

 

Here's an update. The Jeep has been getting weaker and weaker lately, then it started missing below 1500RPM and putting out a blue cloud of smoke from the breather at idle. I ran a compression test and found only 110PSI in #2 cylinder, so I tore it down to take a look.

All of the cylinders show a flower petal pattern that Rangmar said is associated with extremely retarded timing, and #2 was starting to melt. Luckily the cylinder isn't too bad, the scrape marks aren't even through the hone marks, so I should be able to deglaze the cylinder and drop in a new piston.

Timing is going to be more interesting though. I removed my shim stack earlier in the summer to add more advance, so it's kind of stuck unless I do something like advance the fuel cam by a tooth. I also don't use the stock flywheel, so I need to figure out how I'll measure the timing.


You can see the torched #2 in this picture, and #3 is an example of what all the other pistons look like.




Here you can just see the edge of the piston starting to lift/erode at about the 4:00 position in relation to the picture.

 

I should also note, since I saw my original shim stack theory from when my first engine melted down mentioned on another thread, that my original engine did not exhibit the flower petal pattern on the pistons. In the end I don't think the timing had anything to do with that failure.

 

Dang, sorry to rear of your failure! Aren't you spinning your motor at a higher RPM than the rest of us? I think I remember you saying you frequently run it over 4000 rpm. Maybe that's what caused the pattern?

 

hey Red sorry to hear about your engine. I kind of joined the club as well. I have been wanting to update my thread but I have been busy getting the spare engine put in the jeep: (back on the road today) my original engine never quit, ( 28000 miles in 21 months, with 14000 in the last 60 days) , but it was not very happy either. I have not torn down the original engine yet but very soon.
I should go pull the old cylinder head.
I don't know how many miles you got, but for me 28000 hard miles on a unknown $500 engine is not too bad sort of
good luck with your rebuild. I will be going thru my motor was well

 

It frequently goes to 3000RPM on overrun, but it doesn't run over 2500 in constant running. The highest it's ever spun was about 3600-3700 RPM one time, which started to float the valves.

I much prefer running it at lower RPMs, but it hasn't had the torque to do that in a while. When it could pull at lower RPM the vibration was constantly breaking brackets and cracking turbo adapters. When I first swapped it in, it would pull from about 1500RPM with 8-10PSI of boost, then really start spooling about 1900RPM. The past couple years it would still spike to 8-10PSI, but only hold about 6PSI of boost below 1900RPM. During a normal hard pull holding 2400-2500RPM it would hold 25PSI and top out around 105 degrees intake air temp. During a really hard pull like Stevens Pass (13 miles of 5-6% grade) loaded for camping, it would hold 30-32PSI and top out around 130 degrees IAT.

I also have tried several configurations of methanol/water injection. Spraying meth/water would give it a noticeable kick in the pants, egts would stay about the same, but IAT would drop down to about 95 degrees. Injecting just before the intake seemed to make the most difference in power, but injecting before the turbo made the most difference in IAT and EGT. I removed it after about 10k miles of preturbo injection because it had started to erode the leading edge of the compressor wheel.







I did some research last night, and the flower pattern is common and normal in hopped up diesels from added fuel, so maybe it's not timing. The other pistons had a pretty even coating of light carbon showing a lot more even burn, but some coolant spilled on them when I removed the head. When I cleaned the coolant off of them it cleaned the carbon off, leaving only the heat marks from the injector pattern.


This is what my #1,3, & 4 look like


Powerstroke (reportedly somewhat overfueled)


Duramax



I'm planning on doing a few modifications while it's apart. First is ceramic coating the pistons, which will hopefully help distribute the heat more evenly still. I also want to do some porting to the head. I probably won't touch the intake side beyond any port matching necessary, because I don't want to screw up the swirl. The exhaust side has a nasty protrusion right behind the valve that can be smoothed away though, and I bet that makes a noticeable difference alone.


Exhaust - notice the ledge/step. The picture almost makes it look like it's spiraled, but it is not, it's just a level ledge interrupting flow.



I'll have to check the mileage on the Jeep to be sure, but I think I have about 40,000 miles on the conversion since 2012. It's never seemed to have the torque or get the mileage that others have reported, but I'm not sure if that's due to an issue, or lack of aerodynamics. It's seemed to do fine in most cases below 50mph, then hits a brick wall above that if there are any hills. The Jeep scales at 3600lbs with me in the seat.

Finally, I suspect that I may have just found the design limit for shedding heat. During normal around town and 60-70mph freeway driving it wouldn't usually get over 1000 degrees EGT, but during a hard pull it would slowly creep up to 1200 before I would back off. It's possible that this may be too much heat for the pistons to shed to the cylinder walls, and I just got bit for pushing my luck.

 

so you over temped vs overrevved I have never been very happy with my EGT. I often run in the high 1000's, and 1100's. I try to take my foot out of it just before 1200. it is kind of a PIA to drive by the EGT. early in my trip I took out 30% of the rack adjustment I was running at sea level. I still had trouble. some of the big 8%+ hills I was rite there with the loaded trucks going 25-30mph up hill in 2nd

I wonder if it is a jeep thing, are you still at 3.08 rear gear with the ax15? I wonder if I am overloading and not revving enough. but man the engine sure seems to like running in the 2000-2200 range. it runs just fine in 4th, at 2500 too, just seems better at 2000
For mods have you thought about oil squirters. I am working toward them for this engine. on my gen 1.5 today, I have finally gotten rid of the oil vacuum pump and went with the little VW hella electric pump. so far I like it.