Why replace tensioner and Water Pump?

[mikec03]

I've seen a number of posts recommending changing the tensioner pulley and water pump when changing the timing belt. I've had 7 or 8 Subaru's [i've lost count] and I have never done this. The cost of a timing belt change at dealer is $350 but can escalate to $900 [over the phone vague estimate] if all the possible changes are made. The parts alone for above are over $200 for a '95.

 

I usually drive the Subs up to 250,000 mi before the clutch or transmission or ? goes out. But never the water pump or timing belt. I'm I being foolish?

[crash321]

I'm I being foolish?

 

Maybe not foolish but it is a gamble you have obviously won on several times. If your waterpump siezes, tensioner and pulleys grenade, ect, your car well um stops. And if you have an interferance engine stops permanantly until you inject vast amounts of cash to rebuild it or worse yet replace the engine. It is insurance and piece of mind to have it done. You did not mention year, model, mileage.:-\

[johnceggleston]

i bought a 97 obw w/ 98k miles and piston slap and no known service history. i quickly discovered a very small leak on the bottom of the water pump. so i had the timing belt et al done at 98k. the complete job cost less than 600$.

 

the chance you take when you don't replace the pump and pulleys is, will they last 210k miles with out failure. do you replace them at 200k or try yet again? is saving the several hundred dollars when doing the timing belt worth the risk of 1200 - 1800$ head rebuild?

[nipper]

I've seen a number of posts recommending changing the tensioner pulley and water pump when changing the timing belt. I've had 7 or 8 Subaru's [i've lost count] and I have never done this. The cost of a timing belt change at dealer is $350 but can escalate to $900 [over the phone vague estimate] if all the possible changes are made. The parts alone for above are over $200 for a '95.

 

I usually drive the Subs up to 250,000 mi before the clutch or transmission or ? goes out. But never the water pump or timing belt. I'm I being foolish?

 

 

Subaru recomends chainging them "as they have reached the end of thier design life"

 

You may have never owned an interfernce engine. When one of those componenets let go, the valve train stops moving, but the pistons are dtill moving. Pistons can hit valves and make for a lot of damage. If its a DOHC engine you can have valves hiting valves.

 

Also you are only talking parts here. I guarentee you that sometime before the next timing blet change you will need to go in and spend the majority of the money again on labor to replace these parts. There also are the cam and main seals along with re-sealing the oil pump.

 

Finally these are more power ful engines then the earlier ones you may have owned. The parts are under a lot more stress.

 

It is your money to be foolish with. 350.00 vs 2500 or worse 5000 for a new engine is up to you. Just do not blame the subaru when the tensioner you thought was foolish to replace lets go in 10,20,30000 miles and takes your engine out. Murphies rules also guarentees you it will happen at the worst possible moment possible.

 

Preventative maiantanence is never foolish, its just foolish not to do it.

 

Almost all modern engines are interfernce engines.

 

You can probably find a cheaper mechanic for around 650. Why are you going to a dealer for a routine maint item, that seems a bit foolish.

 

 

nipper

[idosubaru]

there's no approach to vehicle maintenance that works for everyone. read, learn, and make your own decision.

 

i need reliability and can't break down or have problems hundreds of miles from home. not everyone needs the reliability i do.

 

also - the main difference you are missing is the switch to interference engines in 96 (EJ25) and 97 (EJ22).

 

in your old 1995 it's not a big deal if the pump or pulleys fail. you get stranded, deal with it, and get it fixed.

 

not so with the newer interference engines. if a pulley breaks or a pump fails, they take the timing belt with them. in an interference engine this means the valves and pistons collide, causing intenral engine damage.

 

so, your idea of just running until something breaks is much more risky and costly in 1996+ interference engines.

 

also, i never ever recommend buying the parts from subaru, they are way too expensive. ebay has complete kits for $200. but that's all covered in other threads here.

[mikec03]

Thanks for the comments. I was aware of the interference problem which doesn't apply to my '95 Sub but does to my two newer one. The interference problem certainly does add a scary element to be considered.

 

However, I still haven't heard of a water pump failure. And there is no reason to just change just the water pump. The three idler pulleys should also be changed since a failure of any of them would cause as much a problem.

 

I do a few things on the Sub's but not a timing belt change.

[nipper]

Thanks for the comments. I was aware of the interference problem which doesn't apply to my '95 Sub but does to my two newer one. The interference problem certainly does add a scary element to be considered.

 

However, I still haven't heard of a water pump failure. And there is no reason to just change just the water pump. The three idler pulleys should also be changed since a failure of any of them would cause as much a problem.

 

I do a few things on the Sub's but not a timing belt change.

 

 

Well part of the reason you dont hear of it is beacuse we replace them before it fails. And once again subaru recomneds it.

 

There are a few threads here for a failed waterpump.

 

But do what you wish, its your money and car to blow apart.

 

I'm going to unsubcribe from this thread.

 

 

nipper

[mdjdc]

Now you've heard of a water pump failure. I've worked on two just this past year for friends where the water pump seized. Had to replace all of the timing stuff and the pump because all of the bearings were screaming. These car ownerss had obviously been ignoring good preventative maintainence. Luckily for both of them we caught the problem before any engine damage was done.

[mikec03]

OK, you convinced me. I also found this write up by "endwrench" which says that one could probably skip changing the water pump at one 60,000 mi belt interval change [ie change at 120,000mi], but not at the 105,000 mi belt interval change. It also has very clear instructions and diagrams for changing the timing belt on a SOHC.

 

I hope I did the URL right.

 

http://www.endwrench.com/images/pdfs/TBeltEWWin05.pdf

[Bubs360]

How much extra would they charge you to replace, say, the water pump with the timing belt as opposed to just the belt? If it's much more, they're robbing you. The water pump takes an extra twenty minutes to replace, I did one on an Outback wagon and had it done in fifteen on my first ever water pump job.

[idosubaru]

Correct - there is missing information in this thread. We are not saying "replace the water pump with every timing belt". Noone says that, except in the case of hte 105,000 mile interval belts.

 

We are saying it should be replaced at some point. Every other belt or 10 years is a good rough estimate. Remember everything is a curve...there's no magic number where things fail. Percentages go up as time/mileage increases....it's up to you to choose what kind of percentages and risk to live at.

 

In general every 120,000 or 105,000 miles isn't very expensive for what you get, a very reliable engine. I generally wouldn't trust a 10 year old water pump or expect one to make 200,000. They can, but not worth the risk.

 

And yes, water pumps fail. EJ engines seem to have fewer failures than EA. Could be just age but they seem like a better design as far as the pump alone goes.

[mikec03]

The cost for the Timing Belt replacement is about $350. The extra for doing the water pump is $130 parts and $50 labor, for a grand total of $530. This is from Sommers dealership in Milwaukee.

 

By the way, I'm just answering the question. It doesn't matter how much it cost to replace the water pump if it's a good idea, and I'm convinced it is.