broken timing belt - due to broken water pump - questions

[Guest D Low From EG]

yesterday evening my car stopped running while driving at 75mph on the interstate. today my local mechanic told me that the water pump broke which cause the timing belt to break. this happened in an 1996 Legacy Outback 2.5L (EJ25). I spoke with a different mechanic who informed me that due to the EJ25 being an interference engine, many of of the valves will be broken. i've confirmed this suspicion by reading posts here for the past hour or so.

 

could a broken water pump cause the timing belt to break? i also noticed the AC seemed to die out right before the car stopped running.

 

my second question is whether this is certain to happen? is there a chance valves didn't break when the timing belt did? or maybe all valves aren't broke?

 

the second mechanic also told me that the only way to determine whether valves are broken or not was to install a new water pump and a new timing belt ($). this solution bothers me because if i'm looking at $1000-2000 for all new valves then i don't really want to repair this damage as the car has 132,000 miles on it and if i will be junking the car i certainly don't want to pay for the labor and parts for a new timing belt and water pump installation.

 

is there any other way to determine the extent of the valve damage?

 

thanks in advance!

d-low from EG

[Guest theotherskip]

the ej25 is an interference engine. when the timing belt breaks, the valves can collide with each other, and possibly the piston head (i'm not sure about that one). the water pump can cause the timing belt to break. if the shaft seizes with the belt being pulled across it, it can try and slip over the teeth, but eventually it will break. the ac dying at the same time seems to be irrelevent to the problem at hand.

 

there is a slight chance that you didn't break any valves, but slight is the key, especially since the engine was probably cruising along at 3-4k rpm. the only ways to check are to either pull the heads off, or put a new timing belt on and give it a try. it is a pretty tough call...

[Guest 1 Lucky Texan]

The ideas below assume you will be paying someone else for their labor.

 

I could see where, by getting someone REALLY interested in diagnosing this, each cylinder could have the cams rotatedin the 'valves closed' position and compressed air counld be introduced via the spark plug hole. A broken off or severely bent valve would vent the air into the exhaust or back through the intake and I guess there would be some sound as well as inability to hold pressure.

 

Pulling the heads is probably the next option. Even if every thing's OK it gives you a chance to have the cams, guides, valves inspected/cleaned and maybe newer BETTER head gaskets installed. maybe install higher performance cams too!

 

It's most risky to just replace the WP, install the new belt to find out there is serious damage. Good money after bad kinda thing.

 

At this kinda mileage, if you feel or can prove there is extensive damage, a used or rebuilt engine may be you best route.

 

just my take on it - good luck!

 

Carl

1 Lucky Texan

[Guest Tolerance02]

I have no experience whit the ej25 engine but the first I would do is removing the valve rocker covers. There will be abnormal free play to some rockers if valves are damaged.

 

Urban.

[Guest ccrinc]

From our experience, if the engine was running at all, you have damage. The faster you were going, the more damage occurs. At 75mph, I'd bet a dollar to a donut that you have broken valves, bent valves, and at least one (if not more) royally destroyed piston.

 

Emily

www.ccrengines.com

[Guest alia176]

I don't understand something here...how can the water pump be related to the "timing belt"? Are we sure the mechanic didn't mean to say the "accessory" suspentine belt? The timing belt does not drive the water pump. The reason the a/c quit working is due to the accessory belt not turning the compressor pulley.

[Guest Tolerance02]

As I said before, no experience whit 25 engine but by all Legacy engines I do know the waterpump is driven by the (back side of the) timing belt. By some makes, like Opel (GM) the T. belt is even tensioned by the waterpump.

 

Urban.

[Guest oobnuker]

Water pump is definitely driven by the timing belt - just took one of these bad boys apart the other day.

[Guest alia176]

Yup,

 

You guys are right. It's the back side of the timing belt that jogged my memory. I remembered how shiny that pulley was! Sorry for the confusion!

[mike golin]

I would turn the cams to the closed position [ cam can be turned freely - both cams on same side ] and use a cylinder leak tester [or regulated shop air around 100 psi ] and check for leakage into intake or exhaust . it is not easy on a 2.5 DOHC but is the best way to check for bent valves.

 

the water pump is turned by the back side of the timing belt . if the pump seizes it will burn the belt off .

 

with only 130,000 on it ,should be good for a few more years. even if it needs a motor you are looking at around $1500.00 to keep it going .

[Snowman]

I have no idea if this is a viable alternative, but I would like to throw it out there just to see. Do you have any idea what it would cost to just get an engine from a wrecked, low-mileage car in a junkyard, put some new seals and such on, and slap it in? Especially if the rest of the car is in good shape, this would make it good for another 100,000 miles, and I would suspect that the total cost would be less than repairing this engine by a substantial amount.

 

Just my two cents...

[canajun2eh]

I'd like to jump in here with my 2 cents' worth: (Canadian 2 cents, by the way)

 

Aren't there two different types of 2.5 liter Subaru engines? The type that has two camshafts on each side (4 in total) is definitely an "interference" engine. The type that has only one camshaft on each side (like the 2.2 liter engine) is not.

 

Personally, I don't think I'd waste my money repairing an engine with bent valves (the "interference" type). Instead, I'd buy a replacement engine from a reputable engine rebuilder. CCR Inc. in Colorado seems to have the best reputation in this field.

[99obw]

I think the likelyhood that the engine is damaged beyond what is wise to repair is very very high. I would go at it assuming that the engine must be replaced.

 

I trust the experience of Emily and the folks at CCR.

[cookie]

Look for a rebuild or a Japanese low mileage take out if you can because junkyard engines are a crapshoot.

If you and your friends have the time and skills a junkyard engine is fine.

In college I used them a lot, but some are winners and some losers.

I preferered to rebuild myself if I had the money in those days, but sometimes an engine from a JY got me by for a while.

It is truly frustrating to have the same problem six months down the road.

If it was a 2.2 I would say you have a better chance in a JY as they are tougher.

[richierich]

Don't go with a Japanese Engine might not have a EGR Tube. Big trouble if it doesn't. If the person would have posted his or her location we might be about to find a shop that knows about Subarus to help him/her.

[myles]

I'd like to jump in here with my 2 cents' worth: (Canadian 2 cents, by the way)

 

Aren't there two different types of 2.5 liter Subaru engines? The type that has two camshafts on each side (4 in total) is definitely an "interference" engine. The type that has only one camshaft on each side (like the 2.2 liter engine) is not.

 

Personally, I don't think I'd waste my money repairing an engine with bent valves (the "interference" type). Instead, I'd buy a replacement engine from a reputable engine rebuilder. CCR Inc. in Colorado seems to have the best reputation in this field.

 

All NA 2.5's are interference.

[Brumby Boy]

timing betl broke = bent valves

the way i check is to renove the roker covers ond then the rockers ond cams so all the valves have to be open then i gut s spark plug of the porcilin etc so im lift wtht the bit of metal that screws into the head then get a metal hose fitting that will jam inside the gutted sparkplug then make sure it is sealed then get some hose and slip it on the fitting make sure its sealed then screw it into the hear and blow in to the head and if you can blow continusilay through the head the valves are bent if you cant the valves arn't bent