Question on interference engine failure, does this sound right?

On a 4 banger 2 pistons hit top dead center at the same time. This is why the timing can be set 180 out and some will run that way.

So yes, 2 can easily be damaged.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >

I've seen those balancer belts break and fray, but sometimes they don't get tangled up in the timing belt.

You really didn't get a very good run on that work, BUT.... if you crashed the valves into the piston tops, you can't really say what the interference gods have in store for you until you open the engine up. The damage could be less, or more, than you have expected. If the mechanic found no compression on two cylinders and good compression on two, there is no second guessing what may have happened. You have to open it up and look.

I helped my daughter swap a Japanese used import engine into her car a few years ago, and it worked out pretty well. It was a Mitsubishi also, and the engine was not too expensive ($300 or so at the time). Her old engine was just worn out, not interferenced.

The Japanese engine store only had a turbocharged engine, but claimed it would work. It did, with a little modification and swap of parts from her old unturbo-ed engine. We rebelted, reclutched, etc while the engine was out of the car.

It was a cheap and satisfactory way to go for her. If you must rely on a mechanic to do your work, you could get into substantial bucks if you are not careful.

OK, that makes sense now. It sucks, but what am I going to do about it? I'm heartbroken, as I really loved that engine. I have a feeling the car will never be the same, somehow. :( I'm going to have the engine replaced. I know the car is 10 years old, but it's not your typical 10-year-old car. Overall, it's in about the same condition as most TWO year old cars. Or at least it was before the engine failure.

Yup, it's looking like substantial bucks, all right. My brother was one of the best mechanics in North America (really, he'd won numerous awards). If he was still around, I'm sure he'd be happy to do the work for me. I'm not a mechanic, and I don't play one on TV, either. But from growing up in a household with a good mechanic, I'm not afraid to tackle my own work on the car, even major work.

However, I really don't have time to mess with it right now, and the rental car bills are going to pile up on me if I don't get the car back on the road soon. This is what has been proposed, see if this sounds about right . . .

The mechanics have located a used engine that they can have shipped in in a couple of days. 66K miles on the engine, $1100, comes with a 1 year/12K mile warranty. With labor and new timing and balancer belts (obviously), they want $2300 total. I asked them about a clutch kit. The clutch never gave me any problems, but the car had over 100K miles on it, and the engine is coming out anyway. They say $250 for the clutch kit.

So we're talking US $2550 for a used engine and a clutch kit. I know that's more than the car is worth, but then again, where am I going to find a good reliable used vehicle for less than three grand??? The suspension and brakes are in excellent condition, the tires are new (about 2 months). The car has no problems that I know of other than the non-operational engine. As I wrote earlier, it is 10 years old, but in better condition than most

2-year-old cars, other than the engine, obviously.

Two questions:

1) Does that price sound about right, for the engine and labor to install it? 2) Since the engine is coming out anyway, anything I should have done to the car besides the clutch?

I was planning to keep the car for about another 6 years. At that point, it -would- have had about 200K miles on it. But now it will have an engine that is slightly newer, I guess.

If you didn't hear a loud bang, 'maybe' the engine is still ok. You might just have a couple bent valves and only need the head reworked.

That would be a far cry from the $2500.00 bill you mention to replace it.

I think the $1100.00 for the used engine is way too much. I would call up the dealer and ask what their price is for a remanufactured engine. You just need the block and head, the rest can come off your old one.

I can get a remanned Jeep engine for $1200.00 or so and I got a 4.2L used engine with 40K on it for mine for $400.00 5 years ago. It is still running really strong.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06 (More Off Road album links at bottom of the view page)

I don't see why the shop wouldn't pull the head to see if you just have a couple bent valves. Even a boroscope might be able to determine if there's any piston damage.

No matter what you decide to do, make sure the hydraulic timing belt tensioner is also replaced. These may fail after they are compressed once and this may have been the reason the replacement belt failed.

Larry

It's one of the reasons we still have the wife's Beretta for a winter car - the dang thing won't die, and the evil I know is better than an unknown evil. You'll know if $2500 is too much or not. If it feels like it is, then sell the car as-is. If it feels worth it, then do it and don't regret it. It sounds like you like the car, so I'd say do it.

I'd consider gaskets and stuff to the engine - especially stuff like oilpan gaskets that are a pain to get to in the car, but easily done with the engine on a stand. Frost plugs and block heater?

I don't know your car, but I do know that on the wife's car, it was WAY easier to change the steering rack with the engine out - it had a slight leak but would have been a major pain with the engine in the car. I'd pop the hood and look for stuff that looks hard/expensive to change and consider a pre-emptive strike.

Ray

Well the shop gave me the option of whether I wanted the head pulled or not. I was told that the job would take several hours, and that the engine probably would need to be replaced anyway. That made sense, seeing as there is a good chance of piston damage. It was a gamble I chose not to take. At best, I would have only saved about 800 bucks by the time the car was back on the road, and that's assuming there was no piston damage. At worst, it would have cost me another 400 bucks or more to learn that the engine needs to be replaced anyway. So I would have been back where I started, but out another 400 bucks or so. And that would have been before I spent a single penny on replacing the engine.

I considered taking the engine home to pull the head myself. I briefly considered it, as I really don't have time to do that in the next week or so (with rental car charges piling up), and the wife was less than thrilled with the thought of a broken engine in pieces in our basement. (too cold to work in the garage for the next few months)

Basically, I was at a point where I had no good options. I could buy a new car, but don't want the new car payments. Plus, my car insurance is really cheap now, as I don't carry full coverage, as I would HAVE TO, on a new car. I could buy a used car. But, I've already got a used car. And unless I spent significantly more than three grand on a used car, there is no way I'd end up with anything reliable. So looking at my options to get my galant back on the road . . .

1) replacement engine, $2300 by time car is back on the road 2) tear apart current engine to possibly rebuild it, ~$1500 to $2700 -or more- by time car is back on the road

Tough choice. I decided if there was a possibility that the repair would cost more than $2300, I might as well take the $2300 option and have some other work done as well. (such as clutch, for example) That way, the extra money I'm spending is actually getting me something in return, other than just more information on why the engine needs to be replaced. In my mind it didn't make much sense to pay someone hundreds of dollars to tell me "Yup, the pistons are damaged". Yeah, there's a possibility of no piston damage, but with my luck, it's likely I've got piston damage.

Will have the belt tensioner replaced also. Thanks

Brand new belts can break. That's why interference engines aren't worth owning, IMO. Junk design from the get-go.

Not unusual.

Nope. Depends on how fast the camshaft(s) came to a stop relative to the crankshaft, and a lot of random chance on when the valves happen to be open while pistons are coming up. If the break happened at low speed, the cam can stop quickly and only *one* valve out of a whole engine can be damaged. You can even get really lucky and have *no* damage... sometimes.

Of course once they have changed the engine they will attempt to repair it cheaply and at a slack time for the workshop. Once done they will likely sell it as an used engine for $1100. That is what makes them their living.

Huw

Have them pull the head FIRST. You probably can just replace a couple valves or replace the head itself. Much faster repair and MUCH MUCH cheaper. No need to replace the engine unless it actually punched a hole in a piston or damaged the bore. Keep in mind the "new" engine could have many more issues than the one you have. Price wise I can find at least 25 2.4s for under 800.00 all over the country. Not sure where you are but punch up

for some ideas on prices.

I sometimes tend to live in the past, but that deal doesn't impress me a whole lot.

There may be a lot less damage inside that what you are expecting. If the head is not cracked, and the pistons are not damaged, you may be able to clean up the valves and toodle on off.

Ideal time to replace the clutch and pressure plate if you have to pull the engine. I cant think of anything else that is really pending.

If you have had radiator problems, or expect them, then this could be a good time to take the radiator to the shop for a boilout and repair if there are any leaks.

I'm going to look around the net and see what I see on that engine. ¨ The one my daughter and I got from a shop in Houston was much lower mileage, (they claimed), and at a much better price. But that may no longer apply.

I checked

There are tons of those engines out there. Some are above $1500, but there a lot of them much less. Some in the $300 range.

You would have to shop carefully for something good and near to you.

Reemphasize, your engine may not be trashed. I am a little surprised the mechanic automatically assumed it was without opening her up.

If you are in a large city, look in the Yellow pages. Lots of people used to import very decent used Jap engines from wrecks. It was said that once a car is wrecked in Japan, it can be more expensive than it is worth to repair it. So these engines were, and probably still are, available from importers at a decent price.

How much do you trust that mechanic??

My Fiero with the 2.5 stripped the timing gear and no damage (well, no damage to anything but the stupid plastic gear.) This was at 75 mph.

My mom's 86 Hyundai lost the belt and she lucked out by having the shop just replace the belt without pulling the head... drove it for another couple of years before the oil leaks and rust embarrassed her too much. (it's still in my back yard and would probably start if I put a new battery in it.) THis was in a mall parking lot.

Sometimes you get lucky. Sometimes you get stuck with a Hyundai. ;)

Ray

And other times, you have a Mercedes diesel that dumps the timing chain under hard acceleration, snapping the camshaft into three pieces and doing unknown other damage that locks the engine so solid that you can't get three degrees of rotation out of the crankshaft using a 10 foot cheater-bar with a 200 pound man bouncing up and down on the end of it.

BTDT...

Gotta love those interference engines when the timing chain/belt lets go. The results are *SO* predictable: Anything from "replace the belt/chain and drive away", to my scenario above, to "What's this valve doing laying in the bottom of the oil pan? - Oh... same thing these pieces of piston crown are..."

I disagree. It's very unlikely that there's much else wrong other than the bent valves. Pistons might be marked up a bit on the crowns but that won't hurt them. You don't generally get much piston damage from valve contact unless the head of the valve comes off and bounces around down there for a while. There's a slim chance a couple of valve guides might be cracked but that's no big deal.

-- Dave Baker

• You can't due a compression test on an engine with a broken timing belt! Totally meaningless. Ths shop is clueless if they think they can.

• Many engines that the book says are interference engines are not. Yours almost certainly is not. I have replaced broken timing belts on a great many "interference" engines that suffered no damage whatsoever. Many of the guides appear to be paranoid.

• Checking for bent valves requires the removal of the valve cover only. I do it all the time. Turn the crankshaft in between top and bottom dead center so no pistons are all the way up. Rotate the camshaft and look for something like normal valve lash. Bent valves will be visibly lower and the valve train obviously very loose.

• Take the car out of that shop and take it to somebody who knows how to fix it. Almost certainly it just needs the T-belt job done over.

Don

Not wierd at all.

YOU CANNOT RUN A MEANINGFUL COMPRESSION TEST ON AN ENGINE WITH NON-OPERATIVE VALVES!! The timing belt broke, the camshaft is NO LONGER TURNING! Some valves are open (no compression) some are not. Some cylinders will have compression, some will not. Take the valve cover off and turn the cam and you will get a completely different set of compression readings. While doing that it is V ERY easy to inspect for bent valves WITH THE CYLINDER HEAD STILL ON THE VEHICLE. The bent valves will remain lower than the others. It is very easy to see. Get the car out of that shop and take it somewhere that has competent techs. I have seen more than one Galant drive away with perfect cylinder balance/compression after the timing belt broke on its allegedly interference engine and ALL we did was replace the timing belt, balance shaft belt, cam, crank, balance shaft seals, water pump and tensioners.

Don