A pulley broke as I was driving on the highway last week, which caused the timing belt to come off. When the pulley broke, the bolt snapped off, flush with the block. The mechanic spent hours trying to...
Where do I start with this one?...There are several things that I see that is wrong with this picture.
OK. To begin this thing, I think I should first say that although you did not mention which engine your 1994 Ford Probe is equipped with, it makes little difference because BOTH of the engines available for that year and model (4 cylinder 2.0L (VIN code [A]) and the V6 2.5L (VIN code [B]) are what is called "interference engines". This means that if the timing belt breaks or comes off for any reason with the engine running, The pistons WILL contact the valves and damage to the valve and possibly the piston will occur.
You probably will not notice or "hear" when this happens. I have actually had one do it in the shop while I had my head under the hood. It made a single, loud "POP" and that was it. Once the valve got bent over inside the cylinder, the piston no longer made contact. However, the damage was done!
Then I have a serious problem with the way the mechanic handled this one.
When an interference engine loses a timing belt, the FIRST thing the mechanic should have checked for is damage to the engine due to piston/valve contact.
This is done by removing the cams from the cylinder head(s) to allow all the valves to close and perform a cylinder leakage test to identify any cylinders with bent valves. Removing the cams is also REQUIRED to get the engine back into time anyway, so this is not a waste of labor.
The mechanic should NEVER have attempted to rotate the crankshaft or the camshaft without the timing belt in place. If there was any possibility that there was no damage done when the timing belt broke, that chance just went down the drain. The fact that the cams rotated DOES NOT mean that there is no damage to the valves.
Then comes the question of the broken bolt. Yes, I can see the possible need to remove the engine to get the bolt removed. If he knew what he was doing, this should be nothing but a thing. You do not trash an entire engine over a bot that is broken off in the block. If the piece cannot be coaxed into simply unscrewing from the block, there are other alternatives, including drilling the hole out oversize and installing a helicoil to restore the threads in the block.
Then with all of this said, I would have to ask about the general condition of the REST of the vehicle. After all, we ARE talking about an 18 year old car here. Is the car itself worth the expense of removing this engine to repair it. Is it worth the cost of possibly having to replace a piston or cylinder head? Only the customer can make that judgement, however, the mechanic should ADVISE the customer in situations like this, based on his overall evaluation of the ENTIRE vehicle. But then again, this should have all occured LONG be fore the engine was removed in an attempt to drill out the bolt.
Oct 23, 2011 |
1994 Ford Probe