Timing cover leak

That's where the major work is. But the OP has to be sure what leaks the dealership told her.

 

Well, this could be making too much of a word ... the stuff in the tube that they use to seal the timing-chain cover is called FIPG, which stands for ... wait for it ... Form In-Place Gasket.

I sort of wish they had used a conventional cut gasket there, because the access there to properly apply the FIPG is really awful. They have very strict specifications for beads of exactly what width applied exactly where, and both metal surfaces have to be squeaky clean and oil free, and you can't bump one with the blob of grease on your wrist while sneaking your arm down where you can't see, or you have to clean it all off and start over. You also have a certain number of minutes to complete the whole job, from when you start squeezing the tube, or ... you clean it all off and start over.

I bet the robot that applies that bead at the factory to a perfectly clean engine on the line is really fast and fun to watch.

I don't know if you could pay me enough to try to do the same thing with the engine in the car.

-Chap

 

Yeah, I could pay you enough with a like, if you wouldn't mind.

 

This makes me wonder: do they throw in the towel and pull the engine for this? Seems crazy though. And yeah, a solid drop-in gasket would make things a lot easier. I know with Honda Valve covers, they typically have a rubber gasket, and instruct to put just a little dab of liquid sealant at two critical corners.

 

Even the Toyota or the Prius has the valve cover gasket, where you apply the sealant evenly.

Y the engine might be removed is if the leak is coming from the timing chain cover.

You can't access or remove the timing chain cover freely, without removing the engine. That's I'm saying.

 

I bet the reasons where they didn't use the gaskets at the timing chain cover, might ha e some reasons. Its not only on the Prius, but on almost all auto brands don't use gaskets on the timing chain cover, but sealant. Atleast, the vehicles I ha e worked on, don't have on those areas, except on the top cylinder head valve cover (rubber seal they have).

 

You're not expected to have to take the timing cover off much. And FIPG cuts down on the number of different prefabricated gaskets to have to keep in inventory. And it might perform better and hold up longer than other gasket materials—when applied by a robot on clean surfaces in perfect factory conditions, anyway.

The tech who changed Xterra72's (see post #10) did so with the engine in the car, so I guess it is possible. If you're on the clock, and you've found a way to do it in half the time of pulling and reinstalling the engine, but you only have one out of three come back again for repeated leaking because of the inaccessible, grimy conditions for applying FIPG, I guess from a bean-counting perspective you're still ahead.

-Chap

 

Problem is, for the Nissan stuff, there's much space in there for the timing cover to be removed, and worked on, without removing the engine. The timing chain cover on that Nissan, faces the front of the engine blablabla. Radiator and the shroud has to go out, water pump, auto tensioner, etc. That creates more accessibility.

But for the Prius, the timing chain cover location is just tight, that even the sealant can't ne applied, without the engine coming out, and even replacing other things like the water pump, chain guides, timing chain, etc.

 

At the 1:22 mark it shows the engine being installed. It might be tough for a DIY job.

 

See again post #10, there's at least one tech who believed it could be done (and XTerra72 has not complained of the engine leaking again; at least so far, it looks like the tech may have succeeded, terrible access conditions and all).

Does that mean I'd want to do it myself that way? Heck no. One thing I know about myself is I have a really low tolerance for low-to-mid-grade frustrations. I can be surprisingly composed and philosophical about some cataclysmic setback, but the low-to-middin' things, not so much. By the fourth or fifth time I would have to scrub off and re-alcohol the whole thing and start laying down another bead with my elbows bent sideways, I'd be foaming at the mouth.

At least the FIPG for oil-exposed joints is only about $14 a tube. If I remember right, the Gen 1 had some coolant-exposed joints where they specified a different FIPG that was $64 a tube back when I priced it. I can just imagine the joy of having to wipe that stuff off half a dozen times and start over....

So for me, I'm pretty sure pulling the engine, while seeming more time and effort, would be effort of a much less stressful kind.

... though I'm really hoping (knocks wood) not to have to do it at all.

-Chap

 

I'm pretty sure that's how they do it at the factory for our Gen 3s, too. Fortunately, we have danlatu, who demonstrated we can pluck the engine alone out the top if need be, which is more the DIY style.

I enjoyed the video at :50 to 1:05 showing the whole instrument panel installed in one swell foop. Funny, they never show the person who has to come in after and plug together the umpteen wire harness connectors.

I'd kind of like to have one of those five-lug-nuts-at-a-time torque wrenches (5:48 to 6:04), though I don't know where I'd keep it when not using it.

I would have guessed they'd put the doors on before the fenders, for easier hinge bolt access, but live and learn....

What's with the rear drum brakes at 2:40 to 3:10? Do some Gen 4s have those in some markets? I notice most of the others shown have rear discs.

And I wonder about the green things on one wheel stud (4:10 and 4:28) that have to be removed by the person clipping in the fender liners. Are those just to confirm that that person was on the ball? Or are the hubs/rotors held together that way before assembly, and that just turned out to be the most convenient person to remove them?

-Chap

 

I have a similar issue as several of you. I was told at my 75,000 mile minor maintenance appointment for my 2013 prius that my timing cover is leaking and would need a replacement. They said that it is a larger leak--trickling, not just seaping--but the oil is only down 1/4 inch since the last oil change 5,000 miles ago (half a quart out of 4 quarts total). Is losing half a quart over 5,000 miles a large leak? If not I'm inclined to just keep an eye on it. Is there any reason to replace other than to prevent dripping oil and possibly having to top it off? Thanks!

 

There's 1.5 inch between the two marks on the dipsticks, and it represents roughly 1.5 quarts. A drop of 1/4" accordingly represents an oil loss of 1/4 of a quart, aka: 1 cup. That's peanuts.

Also, I wouldn't assume that 1 cup is all leaking through the timing chain cover. Have a look for yourself: it's not too hard to get at the bottom of the cover. Remove the passenger wheel, and the plastic panel, clean the area, and monitor for a while. Or quick-and-dirty: put a piece of cardboard under the zone when parking overnight, see what accumulates.

 

I think you would need also, to remove the engine under-panel for this experiment; drips might otherwise just accumulate atop the panel. Maybe just start by removing the wheel and plastic in in the wheel well, inspect and clean the area, then monitor for a while.

 

So, I just took my 2010 in for the TSB oil consumption test (missplacing a little over a quart every 1K) and after 2.5hrs with my car they tell me there is a leak at both the timing cover and the pressure switch. I am also told that they can't do the consumption test with known leaks. From the sound of things I will need to have these two issues fixed (Ext. warranty has ended) before they can test to see if consumption is happening. I didn't get a quote, my tolerance for not throttling people was already maxing out, but from what I can tell based on quotes on the forum I'm looking at 12-16K BEFORE I can prove that there is a consumption issue. There is no way that I am having that kind of loss from these leak points, esp. since I have no oil reaching the ground. Planning to get a second opinion, but engine removal is beyond the scope of my DIY option.

 

Your engine panel, and wherever you park, would be awash in oil, if those leaks were responsible any significant portion of that consumption.

Unless "a little over" is significantly over, I'd probably do nothing, just forget about: isn't the criteria Toyota (arbitrarily) came up: a liter (or quart?) every 600 miles? Your's is fiiiiiiine.....

 

So many bad issues with the G3 engine.

 

I doubt timing chain cover can leak any significant amount of oil. If the RTV is applied properly in factory, there is no chance of oil leak/seep/weep that I can think of unless there is some damage or something. However, the oil filter mount is attached/bolted onto the cover and there are two O rings(if I remember correctly) and it may leak from there and that is very easy fix by replacing them. Or crank seal which can also be easily replaced if found to be leaking from there.

Regarding the amount of room available for timing chain cover without removing engine, I think there is more than enough room to work on reinstalling the cover with RTV. You shouldn't even need to mess with removing/loosening other engine/trans mounts to tilt the engine etc. to make more room. The hardest part for me is squeezing(in uniform bead) out the RTV from the tube to put it on the cover lips without taking too long and not missing areas that need the RTV.

 

Between the Repair Manual instruction for seal packing placement, and the myriad bolts and torque sequence, it's pretty dicey. Have a look at the attached.

 

Yeah, I followed your document but I couldn't follow the very detail like those different bead sizes when I can't get constant output of RTV from manually squeezing the tube. I just eyeball it to make sure there is enough RTV and not too much to avoid having a gap/leak and/or extra RTV causing it to come loose and blocking some oil passages. I just do my best.