5 replies to this topic

[rosso75]

I just broke a timing belt, coasted into the school parking lot, and had to take a math test. Bad day all around, and it wasn't even 9 a.m.

Anyway, I'm wondering if anybody else has ever had a timing belt go out on an 850t, and how much damage you found when you opened it up. I was going about 30 m.p.h. so I'm guessing there is something bent, given that every listing I've seen says it's an interference motor. My labor guide calls for 12 hours to pull the head. If I'm gonna put 12 hours into it, I'm leaning toward just pulling the motor and doing bearings and rings as well.

Any thoughts/opinions/suggestions appreciated.

Thanks

[7 VII 7]

rosso75, on 09 July 2009 - 05:17 PM, said:

I just broke a timing belt, coasted into the school parking lot, and had to take a math test. Bad day all around, and it wasn't even 9 a.m.

Anyway, I'm wondering if anybody else has ever had a timing belt go out on an 850t, and how much damage you found when you opened it up. I was going about 30 m.p.h. so I'm guessing there is something bent, given that every listing I've seen says it's an interference motor. My labor guide calls for 12 hours to pull the head. If I'm gonna put 12 hours into it, I'm leaning toward just pulling the motor and doing bearings and rings as well.

Any thoughts/opinions/suggestions appreciated.

Thanks

Ok, well you do not know how much damage is done to the engine until you get in there. If you have time on your hand you can get a rebuilt head for $450. This includes valves and everything. Usually to rebuild an engine or get someone to do it, it would be over $3,000

You can also buy a used engine and install it yourself... that is a cheap option if you do not have time.

But you need to take the head off to see the real damage that has been done.

[Oreo931]

You are correct, these engines are indeed interference engines. A broken timing belt will usually cause bent valves.

A head job is pretty expensive because it is so labor intensive. I might consider pulling the motor and replacing everything you mentioned depending on the mileage of the car.

[Gaff]

rosso75, on 09 July 2009 - 05:17 PM, said:

I'm wondering if anybody else has ever had a timing belt go out on an 850t, and how much damage you found when you opened it up.

Any thoughts/opinions/suggestions appreciated.

Ugh. I feel for ya. I tossed a belt on my 98 V70 (actually, it was the idler that failed, causing the belt to jump off). The car was idling at the time, so minimal damage possible. Still, it ended up costing over $2K for a rebuild. I think I bent 2 valves and dinged a piston, plus the belt cover was all trashed.

[rosso75]

As fate would have it, I had an extra 850t motor that's in the machine shop now. I was going to build that for my other 850, which the previous owner ran with a bad head gasket until the water diluted the oil and it seized. Unfortunately, my machinist discovered substantial cylinder wall damage on the motor I brought him, and it would have required boring to an OS2 piston. I decided there are other things I want to spend $1000 on instead of 5 pistons and rings, but I hadn't planned on "other things" being the motor in my other car.

I thought about a used motor. However, my machinist did one head off a Mitsubishi 24v V-6 for me, replaced 2 valves in the process, and got me a complete head gasket set for $400. I should be able to get this head done for about that, I already have a head set (came with the car with the blown head/seized motor), plus some bearings, some rings, a hone on the cylinders, maybe turn the crank if needed....should be less than a grand. For that I get all new. If I put a used motor in, I'm spending a chunk of money for an unknown.

[shepworldwide]

before doing all of this spend the $50 and retime and replace the timing belt.
we can all assume your motor is toast but what if it's not
$50 > $1000's + labor
if your motor is toast well you'll need a new timing belt anyways so now your ahead in the game