Does Subaru STILL insist on using rubber timing belts??
And why do interference engines even exist? Many non-interference motors have excellent power and fuel economy.
Ok here it is.
The dealer who has the car now is claiming that the timing belt apparently jumped, it did not break. OK. Perhaps when the belt was replaced last year an error was made by the Subaru factory trained technician. @#it happens.
I spoke with the dealer who replaced the belt last year and I will be towing the vehicle over to him. He will have a look and after which we will talk. He claims that they did replace the tensioner when he replaced the belt and water pump. I will have to dig up my service invoice to verify.
Maybe a couple of heads is all it needs. The dealer who has the vehicle now feels that a completely rebuilt engine is the way to go. It is a labor intensive job apparently. More cost effective perhaps is his reasoning.
Let’s see what the guy who did the timing belt replacement has to say.
Question, how hard would it be for an average back yard mechanic to replace the engine/ heads?
BTW I contacted Subaru America about this. No love there apparently, go figure.
If you have the time and the patience it’s not a bad job. To replace the heads you’ll be pulling the engine out of the car anyway. In a shop with proper tools a guy can have an engine out in about 3 hours. I’m guessing that at worst you’ll need a valve job or a couple of rebuilt heads (same thing, really). I don’t really recall seeing one of these engines do piston damage when a belt breaks–it’s not a Kia after all!
As to some of the other comments, interference engines are found in belt and chain driven models. I’ve seen old Chevys bend valves when the chain goes. As for the belt vs. chain preference, I’d rather replace an $800 belt than an $1800 chain. And timing chain services are quickly becoming more commonplace. Be careful what you wish for.
Why is there regular and extra krispy kfc chicken? It is a corporate decision based on cost and demand.
A guess on my part might be that the harmonic balancer you referred to as becoming unbonded may have caused the timing belt to jump due to some lurching involved.
Assuming for a moment that the valves made contact with the pistons, in most cases only cylinder head damage will occur. However, that’s not a given.
In some cases pistons can crack, rod bearings become damaged, or connecting rods may bend a bit.
If this occurs it will not be noticeable with the heads off and problems may surface immediately or at some point after a head repair or replacement is done.
In a nutshell, sometimes an entire engine may be damaged due to a broken timing belt. With the design of the Subaru engine there is no way of really determining any rod bearing fault or potential cracked piston short of splitting the block, which then means a complete overhaul.
The keyway on the crank should be carefully inspected also and if a chance is taken on head repairs only then any nicks in the piston tops should be ground smooth to remove all sharp edges. Failure to do so may create pre-ignition due to the sharp edges glowing red hot. Think of it as diesel glow plugs.
never run the numbers. what is parts and labor for motor replace? 2k labor, 4k motor? approx? your bill should itemize expenses. if true, than replacing cylinder heads or fixing cylinder heads should also be itemized. so, head job is 2k labor, 1k head work? or something in that range. point is, you are only replacing heads vs swapping out entire motor. there should be a huge price difference for the 2 jobs. unless mr.mechanic here says his labor is actually 88% of job
I think you need to talk to your daughter and get something cleared up. Did she hear any unusual noises when she shut the engine off? This is the most likely time that the belt broke or skipped. Did she hear anything unusual when she went to start it, at the moment the starter first engaged? If she didn’t hear something like a hammer hitting something once, then you may have dodged the bullet.
If the belt just jumped a tooth or two, there is less likelyhood of valve damage. The damage is done if the valve is fully open when the piston comes to TDC. The cam and crank would have to be off time by quite a few degrees for that to happen, one or two teeth would not do that.
Under no circumstances would I reuse this belt, even if it doesn’t show any damage. If it did just jump a few teeth instead of breaking, you maybe able to tell. If it has a distributor, see if the rotor is turning when the engine turns. I doubt is has a distributor though, remove a valve cover and see if the cam turns when the crank is turned. If it does, put on a new belt and go for it.
If the belt jumped, it is likely that the tech forgot to torque down the bolt that goes through the tensioners pulley and the belt has been relying on the spring all this time. However I am more inclined to think that the belt is broken due to a defect, but at the low RPM of shut down or cranking, when it did, there is a good chance that spring pressure would have positioned the cam with the least number of valves open and those that were opened would be only about half open. Good chance for no damage.
If the belt is broken, the shop should do a leak down test on all the cylinders that the valves are closed on, then rotate the cams 90° to check the rest.
I’ve Never Experienced It, But A Certified Technician Who Has, Once Told Me That A Weeping/Leaking Water Pump Can Saturate A Timing Belt, Softening It, And Sometime When Somebody Hits The Key To Start The Car . . . Z - i - n - g . . . Off Go Some Timing Belt Teeth.
I realize the OP replaced the pump at the last T-belt change, not long ago, but I wanted to throw that in so people could have some fun with it. Even new parts or labor sometimes fail in a short amount of time (or right out of the box).
CSA
Shop that did work over 1 yr will inspect car. It’s not my call about goodwill or make it right or do a deal. We will see what they say
No unusual sounds were noticed by my daughter when she turned the car off the day before or the following day when the start was attempted. Mind you she probably would have not thought anything of it if she did. Perhaps if there was a 100db bang at the time she would have remembered.
When you crank the engine there is a rhythmic tinny knocking sound.
I can believe the theory referencing torquing the bolt on the tensioner. That kind of thing could easily happen to me I am afraid.
I did notice in my invoice for the belt replacement that the tensioner was not replaced.
The car is now back at the shop that did the original belt replacement work.
I will post the results when I get them.
Thanks for the responses so far.
“I did notice in my invoice for the belt replacement that the tensioner was not replaced.”
Well, no matter who was responsible for deciding to not replace the tensioner, now you have found the smoking gun in the case of “Who murdered this engine?”. If the service facility did not recommend replacement of this part, their judgment is certainly questionable. If the OP decided to economize by skipping replacement of the tensioner, clearly that was not a way to “save” money.
Unfortunately it does sound like the valves have been damaged. Along with the other options to fix that you might want to consider getting a rebuilt engine from these folks. You will have a good warranty on the engine which will basically have zero time on it. It isn’t a cheap fix but if you plan to keep the car for a long time it may be worth while.
Not replacing the tensioner is not a smoking gun. I don’t replace the tensioners in my vehicles and have never had a problem.
@twinI would hardly default to “replace the engine” as the mechanic seemed to do.
Exactly…or
I can hear it now with some unsuspecting smuck…“Your oil change is pass due. You need a new motor !”
The tensioner is looking like the place to focus on. Replacing a part like a water pump who’s failure would be no more than an inconvenience vs replacing a critical component such as a tensioner is a no brainer. In times of budgetary constraint the tesioner would definitely take precedence. I would also think that as part of the 100K mile service replacement of the belt, a tensioner would be part of the package.
End to this story.
I just got my car back the other day. Cause of my problem was the timing belt had slipped a few degrees. The reason for that can not be 100% ascertained, only 99%. My opinion from what I have learned here and at other places is that when the belt replacement was done the tech did not torque the tensioner properly. The rest is history. Bottom line is I had the pistons replaced, heads sent out to a machine shop, valves etc. The bill was about $1600 for that work. The dealer worked with me on the charges. Not extremely satisfied, but not fuming mad either.
What did I learn? Don’t overlook what seems to be the long shot. In my case that was the timing belt replacement process being botched by a top rated Subaru dealer.
I also learned that Subaru America has a dark side!
“Not replacing the tensioner is not a smoking gun”
After reading the update from the OP, it appears that you are wrong, Keith.
You may have avoided problems even though you don’t replace your tensioners, but I believe that this is a very bad way to economize. And, something tells me that the OP agrees with me.