blown Prius Engine

That was my thought, too, but I don't know enough about repairing blown head gaskets.

But if he spends $1,600 on whatever repair he decides, and let's say it lasts another year, I think he would get more than his money's worth given the amount of miles he drives. So, if the costs are $1,600 (even as much as $2,000), I'd fix it rather than throw the car away. Once the cost gets higher than that, I might think about buying a new car.

Mike

 

The battery outlasted the gas engine? Are you kidding me? The battery was supposed to die at 100,000 miles.

 

Here's what I would do, pay to have it repaired, a machanic will have the machine shop flex and mill the head as needed and check valves ect. Make sure they do a complete coolant system flush.

 

I had a couple of burnt valves on my 89 jag, which required new heads and head gaskets. only risk on this Prius is that the head may need to be milled. i'd get a new head gasket, grind the valves and new valve guides, then drive it until it dropped ... again. far cheaper than replacing the car.

 

Dumbmike who says "throw the car away"? We are saying it may be cheaper to buy a lower mileage motor and swap it in then replace the HG on a motor that's been rode hard and hung up wet. I'd call around locally and see what he can grab with cash out of a bone yard and for god's sake don't do any of this at the dealer. If you do the car will be essentially totaled anyway at there $125+ an hour labor rate.

Save some money wherever you can OP as you got more bills coming on this car.

Initial quote on just replacing the gasket is great till they take the valve cover off and pull the head and find out the motors wiped out anyway. Its got coolant in the oil etc etc...Blown head gasket is rare on a Gen III. Something bad happened.

Its pretty easy to pull the motor out and less labor than a HG I bet.

Lets see what the op is quoted for a HG repair. Then lets see what it costs to ride out the door.

 

Esprcially according to the TDI sites.

 

I missed the part about it being rode hard and hung up wet, just that it had 175k on it.

 

60,000 miles a year is rode real hard in my book. That's almost 200 miles a day 7 days a week for 3 years non stop.
Must be delivery or taxi. If either of those endless stop & go.
Motor just gave up. Really good run. I wouldn't even consider a new HG. Car probably eats oil bad and just ran low on oil once and overheated. You don't know because there's no damn temp gauge.

Lets see......if that was my car it would have seen:

6 trans fluid changes
36 oil changes Mobil 1 OEM filter
2 engine coolant change
New rad hoses
ICE water pump
6 Inverter coolant change
Inverter coolant pump
2 serpentine belt
sparkplugs
6 sets of tires
2 sets front & back struts
1 set cv joints
1 set front lca's (ball joints)
2 brake fluid changes
all new brakes front & rear

 

ed,

This is all fiction. Until the OP shows up, we are all speculating.

I have a bank courier buddy with +350K miles on his Gen2. It has recently started consuming oil at ~1800 mi/qt.
This is from worn valve stem seals. Compression leak down test is great. He has had one battery module replaced in the HV battery pack, $40 for the used module and labor from a small shop to install it. That is it for unscheduled maintenance.
(His previous car was an Accord wagon, 1.4 MILLION miles when retired for the Prius. No engine overhaul, just a head gasket and multiple valve stem seal replacements with the head on.)

I think racking up these highway miles quickly is much easier service than a bunch of short trips over 10 years.
If this engine was not using oil, did not overheat while the head gasket was going bad, there is no reason to throw it away. ( do Gen3s give a coolant overheat warning light or CEL?)
175 K miles is nothing with modern cars.

I could have the head removed and dropped off at the machine shop before lunch time.

And just for the record,,, when an engine runs low on oil, it clatters and self-destructs quickly, NOT "overheat".
And Gen3's don't need 5k oil changes. That's a waste of good oil.

 

Completely agree. My father got 1 car and 1 truck with over 300 K miles each and they are still in good condition. But sure he is soft on the gas pedal and he's a mechanic, but he did not work on them that much, the rust in the main concern.

Edit: Here's a picture!

 

Weirdly enough, head gaskets are simple. Between the block (where ye cylinders, pistions, et. al. live) and the head (where valves, spark plugs, and camshaft(s) live) is a tough rock-em, stomp-em gasket. Between the two hunks of metal you have the four bores (cylinders) where the pistons live and multiple channels through which coolant and, separately, oil go. It's a tough life for a gasket in there: High pressure and flaming gas-air mixtures, oil at anywhere between 30 and 90 psi, coolant running around at (nearly) atmospheric pressure, but at or over the boiling point of water, and, of course, the Outside which is at atmospheric pressure.

A blown gasket basically connects two or more of these various things together. You get oil in the coolant, coolant in the oil, coolant sucked into the cylinders, exhaust gas into the oil, oil into the exhaust gas, and so on. When you see a clunker heading down the street emitting huge clouds of white vapor, well, you're likely looking at a car with a blown gasket. The coolant gets funny colors, the oil gets all light brown and foamy, and so on.

The solution is pretty much fixed: Replace the gasket. Now, on most cars, this can be done without removing the entire engine from the car since, natch, the head is on top. However, pretty much everything that goes into or comes out of an engine (exhaust, intake, et. al.) has to be removed in order to get the head off. So, off comes the fuel injection, exhaust manifold, pulleys on the side, all the covers on top of the engine, etc. Once all the junk is off the top of the engine, the head is, by comparison, kind of an anticlimax: a dozen bolts or so that get unscrewed, then the head lifts (pried, hit with a large rubber mallet, cursed at, etc.) right off. For somebody who knows what they're doing, it would probably take a couple-four hours to get to this point. For somebody like me, who's a back-yard mechanic at best, probably a couple of days, putting all the parts in baggies and staring hard at the Chilton's/Official shop manual as one goes.

If you're lucky and the car manufacturer is being nice, you can get a kit of replacement gaskets (not just the gasket for the head, but ones for the manifolds and whatever else gets destroyed when the head comes off). One carefully cleans off the top of the head, which is a nice flat surface, being careful not to drop chunks of gasket into the innumerable holes on the top of the engine. After it's nice and clean, a metal straight edge is carefully drawn across the top of the block. Engines that have been abused have been known to warp; that's usually the Death of an Engine, but, if it's not too bad, a machine shop can plane the surface flat again. Weirdly enough, an engine works OK after this treatment.

The head itself is an interesting question. As it happens there's tons of spring-loaded circular valves mounted in the head. The valves themselves, around their circular rims, have precise shaping with certain angles machined in. The valve seats, which is simply the circular area on the head into which the valves fit, also have particular, accurate angles. On old engines (that is, engines that actually need an overhaul) the seats and/or valves typically have black chunks of carbon plated on. As you might imagine, this means that said valves leak. That's bad enough for intake valves which are, when they're open, exposed to a relatively cool gas-air mixture. Exhaust valves when they're open are stuck right out into the ridiculously hot combustion products. Their only chance to cool off is when they're shut, in which case the heat is conducted out through the rim of the valve into the seat. If there's chunks of this or that in there so a good seat isn't maintained, said valve can literally burn (i.e., iron will burn, just like wood, if it's hot enough), at which point it's not very much good as a valve anymore.
Other interesting things can happen to valves. The stem of the valve goes through a hole in the head; there's gaskets in there and all that which can wear loose, and the stem can wear the hole so things wobble. Further, the camshaft (which presses on the valve stems) lives in the head, too, and there's bearings and such in there that can also wear. For a full overhaul, the head gets fully disassembled, cleaned in really nasty stuff to get all the junk off, all the wear points are replaced, the valves reground, the valve seats machined, and so on: A job for a machine shop, in my view, unless you're a masochist.

The good news is the relative health of a head and all its piece parts can be determined without taking the whole thing apart. A smart person with a feeler gauge, the specs, and a proper eyeball can determine just how much of a fix, if any, a head might need. If all that's wrong with a car is the gasket, the guy looks and measures the head over with tools and an eyeball, puts the gasket (along with the sealer) on the top of the engine, and bolts the head back down. If the head needs work, it's handed off to a specialist who beats the heck out it it (valve job by name), hands it back, and life continues. At this point everything that was pulled off the engine goes back in reverse order (you marked all those baggies, right?). The place that always gives me the willies is getting the timing belt back on right - be off by a notch or two and it's possible that one might actually break something (some engines have the angles and such where it's possible to have a valve open when the piston comes the other way; it's not a pretty picture), but usually the engine just sputters a lot and tries not to run. Chilton's and the shop manual typically have all sorts of things that one does to prevent this: This is the place where it really pays to pay attention.

As nasty as all this sounds, your basic head job is something that back yard mechanics, who wouldn't go near a standard or automatic transmission on a bet, tackle all the time. Of course, since they don't do such stuff on a regular basis, they'll need the time to get it all done. There are people in machine shops who do this stuff day in, day out, for 10 years past mandatory retirement age. As you might imagine, they tend to be quick about it; shops compete with each other; and, as a result, a valve job (which includes a head gasket replacement) tends not to be wildly expensive. The dealership would rather sell you a new car. Further, valve jobs and such are a bit out of their range of replacing large hunks of this and that during warranty repairs, doing brake jobs, and other standard maintenance, so they'll charge you for the privilege.

KBeck

 

Sorry for the over-statement. My fault.

My only point is that in the cost benefit anaysis, if you pay about $150/month for repairs on a car that is paid for, that is probably better than buying another car, especially buying a new car. You might use different numbers, but I think you get the idea.

On another thread, a guy had to pay $3,000 for a new brake system (attenuator?) on a car with 50K miles on it. I think I'd pay that cost (though not happily) because I think I'd get my money back on the purchase over the years' worth of use. (But I think he will get a complete reimbursement in the end).

By the way, I agree it might be cheaper to buy a used engine and swap it in. I'm only trying to give what I use as dollar amount versus expected time of use rather than just say that it might be cheaper (or more expensive). This way, somebody can use the same idea with the next expenditure.

I hope that explains what I was getting to. Again, sorry for the over-statement. I wouldn't throw anything away, even my car (except that I have my cars for so long and I just donate it and get a $200 or less tax deduction).

Mike

 

Everyone has a different threshold of throwing good money at bad.

 

But isn't that the issue? I have my approximate numbers that I follow. Some will rid themselves of the car at the slightest hint of a problem. Others will hang with a car until the very end. You are right: Different thresholds.

Mike

 

This is way above and beyond the call of duty. I think I learned more about engine repair today than in my entire lifetime. Thanks for responding.

Mike

 

Looks like the OP has no interest in repairing.

 

The OP asked why this may have happened. The corrosion inhibitors in the coolant only last 10years or 100K mi. It's possible it wasn't changed at 100K. Once the inhibitors are gone, the first thing that the corrosion starts working on is the head gasket.

 

Colm,

So the coolant suddenly goes really bad at 100k miles or 10 years? That's a really big spread of numbers.
My coolant at 126k looks like brand new and tests fine with the test strips. It is now 4 yr old coolant.

Come'on OP,, the speculation is getting deep here...

Please post pics of the failed part if you go for repairing the head gasket, Thanks.

 

My 2010 Prius with 175K did the exact same thing in Cyl. 1. Changed oil and all maint. It appears that in these models the #1 cyl. is the problem Ours would rattle from time to time and we were told that it was normal. A blown head gasket is not normal. Should be looking for a recall. We need to file a formal complaint with fed. gov't.​