1nz-fe Cam Swap

I think you have a higher probability of retrieving the Allen wrench by taking off the timing chain cover.

 

Looks like you're right; I took the oil pan off of this 1NZ-FE engine to see if I would be able to access anything there and it looks unlikely. On that note the 1NZ-FE oil pan didn't look too bad after 150k miles or so, just a thin layer of grit and grime in there but no visible metal chunks or flecks or anything. After reading your advice and doing that I decided against pulling my oil pan, also having read about about the difficulties of re-sealing it around here in the past. Wasn't able to get it out with magnets so.... allen key stays in!

I've got the cam swap done so that part all looks good. Engine runs and idles fine, no scary noises yet from this 2mm allen key in the timing chain cover. I haven't tried driving it at speed yet.

My calculus is that the effort it will take to remove the timing chain cover and replace it (requiring draining coolant, requiring a new radiator because my coolant bleed plug is in terrible condition) will take me several days and be worth the cost of just replacing the engine if it comes down to it.

So now I learn to live with a 2mm allen key somewhere in my engine! But, you can avoid this yourself by just putting a good ball of duct tape around your allen key handle that you use to pin the timing chain tensioner release in place.


I spent probably over 24 hours on this, but I think I could do it in maybe half the time if I were to do it again.

Some notes

- You should jack up the right side of the car to crank the engine from below if you need to (I didn't have a socket short enough to crank the damper wheel from above, meaning a lot of cranking the damper wheel from below then going back up above to see if the timing chain marks lined up)

- It seems a "full 360* rotation" of the crankshaft as described in the manual to get the timing chain marks to the proper location takes several rotations of the damper wheel. I was worried originally when I turned the damper wheel 360* clockwise and the marks weren't lining up; I had to turn it 360* clockwise about 20 more times. Then I overshot it and had to do it again. Then I had to do it again for checking the valve clearance, which was quite the workout. After replacing the cams it was noticeably harder to crank the damper wheel, presumably due to the increased compression.

- The timing chain tensioner mechanism is a pain to access, as there is very little space to insert a screwdriver. I ended up hacksawing off the tip of the largest flathead mini screwdriver I had, gripping that with a vicegrips such that the screwdriver was perpendicular (perhaps "normal") to the vicegrips and used that to pull up on the tensioner mechanism. With a little practice I was able to use that to pull up the tensioner release, release the tension, move the release back down while holding cam with a wrench, and insert an allen key to block the tensioner release (with tape around it this time to prevent falling in). It took me some time to figure out how to do this properly.

- Removing the exhaust cam gear from the exhaust cam is tough; the bolt was stuck on pretty good. After I had completely stripped it, I ended up putting towels everywhere to cover the motor, and using a dremel to grind off half the bolt until I realised that I could grip the washer under the bolt with a vicegrips and twist it off that way. I probably still got some metal dust in my engine. I guess grip the wahser with a vicegrips if that bolt isn't coming off. Worst case you may have to grind it off. I poured a bunch of oil down through the timing chain cover a few times to wash down anything that may have gotten in there (including that allen key...)

- You don't have to remove the VVTi gear (big cam gear); you can (and probably should) just transplant gear and cam whole there

- It appears some slack may get around the other side of the VVTi gear making it appear there isn't enough slack to remove the exhaust cam gear. At some point I managed to pull the VVTi gear (maybe the cam and gear) back around and realized that was where the extra slack was.

- Valve spacings were within spec; they seemed to be towards the low end of the spec on the intake cam

Anyway I'm sorry about bungling this video here; I had to get the car out of the garage by this morning and I barely got it out in time (7am), but I'll do my best to get together a guide at least with all the details I encountered. I also probably executed this in a pretty non ideal way in terms of a video guide but I want to learn about ICE's here so mission (partly) accomplished.

 

Awesome update, keep us posted on this power mod!!

 

Has the engine been run since the allen key dropped down? The reason I ask, is because I found this picture of the timing chain cover removed (on a 1NZ-FE) :

What worries me, is that there is not much room at all at the bottom the the timing chain area. If that allen key gets in there, I can imagine that bad things will happen, and, replacing the engine will actually require replacing the coolant anyway. It might be possible to drain the coolant by using the lowest pipe on the radiator or something rather than a bleed valve?

(I found the photo here : Ebay timing chain kit - Toyota Yaris Forums - Ultimate Yaris Enthusiast Site - haven't read the thread but the picture raises concerns if a solid metal tool has dropped down into the timing chain area...)

 

It has been run, and thanks for the photo! Currently, I don't really have the means or time to rip off the timing chain cover in that I can't reliably store my car and work on it for days. So that's my current compromise. I did notice when pouring oil through the timing chain cover that a tiny shred of rubber from a flexible strap I was using that had fallen into the cover, poured out with the oil. I tried to pour oil into it at all angles and locations. So I have some hope that it made its way to the oil pan, or into some sort of drain. At some point in the future I may re-evaluate this decision, by choice or otherwise

I drove the car home from work going 80+ with no problems. (live free and die hard; is that how it goes?)

- Definitely hauled much better up hills and keeping up with traffic. Required much less throttle input in general and seemed to be 1000 RPM less doing the same thing in any uphill situation

- Sounds cooler, also louder. It's definitely not loud, just louder than before. I've only removed the resonator because I'm eventually going to do an intake

- I have to retune my driving for sure, and the ECU will have to relearn the engine

- I feel like I was getting torque steer, which maybe my alignment is off from removing and replacing the strut tower brace bolts to remove the brake fluid reservoir bracket

- Seems to roll forward just a little bit faster than before when I have it in drive with no inputs


I did try getting some pre-mod logs in the Torque app, and actually went out and re-did it because I did it badly the first time, and still screwed it up by getting too many data points. So now I think I can get a decent test together but I'll have to see how it compares to my earlier data. I should at least be able to get a 0 to 60 comparison from the data worst case.

 

What about the hp/tq levels you were getting in TorquePro...even if they were off, are you seeing higher readings now?

Are you happy with the mod??

 

I haven't even tried hooking it up yet, I want to run the same test at the same location at the same time of day so I can at least get some comparison. I'll get the figures together when I do the test, probably later this week!

 

Also as for whether I'm happy with it, I'd say absolutely. I bought a Prius on pretty utilitarian premises, and since I like to tinker I've ended up really enjoying improving various aspects of the car and learning all about it. In terms of what this mod has promised, I'd say that it's delivered so far -- definitely more responsive and seems to have higher torque at lower RPMs. In terms of "butt dyno" I'm feeling pretty good about it. (hopefully that's not just "ear dyno", but I really seemed to be keeping up a lot better at changing speeds, and going uphill the lack of wheezing and flooring it occasionally was noticeable)

It also seemed much less sensitive to losing momentum going uphill; before the mod I would hit the right RPM I needed to maintain my speed, and then ease off the accelerator a little, and feel like I lost a ton of momentum and have to build back up. That feeling seems to be much less present; I can ease off the accelerator and then pick the speed back up again much more easily

I'll need some time to tune my driving (also I'm going to put in that RedBullet sensor that @NortTexSalv04Prius mentioned, USPS just left me a notice today; it already got here from Taiwan). I'll probably wait a week or two just to get an idea of fuel consumption.

 

Where is @Toyota Jesus ? Not heard fr him ever since the cam swapped, and inverter mod.

 

I PMed him asking about this mod and did get a message back from him, he said he's driven about 20k miles with the new cams and hasn't noticed any problems so far. There's been no more news on the inverter mod, that I know of

 

Thanks so much for the response.
I pretty much think the inverter mod may not have worked or so.

 

I guess I can't blame him for not wanting to do it by sequentially blowing up inverters, it is an interesting concept though. I wonder if the inverter tolerates any useful amount of over current at all from the battery; the best way to save on inverters would probably be working up from a very small value, increasing it by a small increment every week or so until it blows, and then using a value maybe 2/3 of the one that tripped the protection (if that's even a useful amount)

I won't be doing this just yet, but it seems that it might be possible to find parameters here to make this a bolt-on

 

Soooo

Looking at this and the pic @landspeed posted, it seems like if it hasn't eaten up/been eaten up by the timing chain, the very likely outcome is it making its way into the crankcase (which is not a great outcome either, but actually I think preferable to the timing chain in terms of possible damage done by a 2mm hex key, as long as it isn't recirculated indefinitely.) I may have heard some thunking sounds when I initially started it up, that actually would be consistent with a hex key getting chucked around by the crankshaft a few times, but it's very hard to tell if that was from starting an engine that had just had a cam swap done on it.

The one thing I'd like to get more information on is these little arrows going up into the oil system from the oil pan; just how the oil gets down there. Also if the hex key does get into the oil pan, it may get picked up by my magnetic drain plug, meaning this product might be good for something after all...

 

Yeah, I'm starting to guess the oil pan:

Oil pan subassembly top view: (the bottom of crankshaft housing; the crankshaft rotates just above this and oil comes in from the timing chain cover on the right)


Bottom view:


Well I don't think there's much chance it would be going up through the strainer having had a look at it.

And the oil filter is looking less likely:

 

Just open that oil pan and check, instead of thinking whether it would be ...
Except you don't want to open up timing chain cover, and all that to check and seal everything back.
If I were in your shoes, I'd disassembled everything.

 

I might get around to doing that; the oil pan is starting to look promising. I'm going to at least change the oil and filter first, though, and see if I get lucky with this magnetic drain plug... Also I'm going to see if I can drag a strong magnet along the outside of the oil pan to get the key to the hole, if it's in there

 

Saw this page a couple months ago and thought it was pretty cool so I'm giving it a try.

I'm hoping the anecdotal evidence of this working isn't falsified; I am in the process of rebuilding a whole motor and installing the 1NZ-FE intake camshaft into that. I would have just switched it over to my current engine, but its at 270k miles and burns a heck of a lot of oil. I was worried the increase in compression ratio would exacerbate that issue and possibly cause an engine failure anyway.

First step was to find a used motor, this one at pick n pull was in surprisingly good shape. I had no mileage information, but it seemed like either very low mileage or very well maintained. There was almost no oil staining within the engine, all of the valve lifters were in very good shape, the bearings looked reusable (of course I still got new ones). The only thing I didn't like the look of were the valves, they were very dirty and carbon-ed up. (I almost feel bad for tearing it apart)


(The transmission didn't want to separate so I ended up needing to hoist it in the air and wail on it with a mallet for a bit.)



I tore apart the engine and put every nut bolt and part in a bunch of different ziplock bags I had labeled.

After that there wasn't much to do other than clean the engine and wait for the new parts to arrive:


(I am bad at taking progress pics, that is the block with the lower half oil pan and head removed)

-New gaskets and o rings
-New piston rings
-New main cap and connecting rod bearings
-New valves
-New head bolts

Currently in the process of reassembling the engine, new pistons are in and the head and oil pan are installed.


(Obviously that is before the connecting rod has been attached to the crankshaft, pic was taking halfway through compressing piston rings and installing pistons)




Thats's where it sits as of today, currently in the process of setting valve clearance.

I'll be sure to update this as I go.

 

1nz-fe cam swap/engine rebuild attempt | PriusChat

Not sure how to get the embedded pics to work, there are all the picture in an album on this site.

 

Hi Patrick,
would you know the significance of the number stamped inside the camshaft follower?
i'm doing valve adjustment on my 08 prius and i have 2 intakes that are out of spec.
readings are 0.011 & 0.013 , they off by .003 and .005 respectively from my target 0.008 clearance. i just want to buy the follower to fix them.
also the stamp/etch inside the follower have numbers 40 and 37 respectively. hopefully you know the answer, i looked but i cant find the key word to find the answer.
Thank You
CK

 

The repair manual section EM Engine Mechanical has the procedure for checking valve clearance and has the calculations used to determine clearances and charts to determine the shim number to purchase.