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Hi, I have an Opel Combo 1.7 (2005/06) model running on diesel. One day, while driving, I heard a bang sound, and the engine stopped running. At the workshop, the mechanics told me that the timing belt has rubbed (about 25-30% of teethbed has rubbed or flattened), can this cause engine damage?If so, how to tell engine is damaged or affected by this situation without taking the engine apart?What would it costs to fix any engine damage (estimation in USD). Any suggestion to this problem?If it is due to timing belt, any possible methods to prevent this from happening again other than changing timing belt? Thanks.
Before this problem, I had (about 1 month ago) asked a work shop to change clutch, flywheel, water bump, and engine mounting. Could this problem related to improper workmanship during changing or replacement of any of the above?Could this problem related to leaky fuel pump?
Hopefully i can help..
If the belt has indeed gone / slipped or become very loose then yes this can in some cases cause internal damage or bend the valves as the engine is classed as an interference engine - the only way to really determine that fully is to do a compression test on the engine or each cylinder - so you'll need to remove all 4 glowplugs to fit the compression tester in using a suitable adapter - but you need to be extra careful removing these plugs as they can tend to get seized in the head and suddenly shear off - as long as you soak them in lots of wd-40 etc and slowly work them out the head then you should be ok - Ideally before you run a compression test you will need to have the engine re-timed back up with the a new belt fitted/tensioner/guide pulley..and check to see if the engine will fully rotate by hand a full revolution without locking up,if it does then you will likely have internal damage - if not, then a compression test can be done to identify on which cylinders, the damage has occurred on if any - once you know which ones it is out of the 4 or lacks compression - then the head will need to come off anyway to replace the valves or replace the head if you can get seconds hand ones - plus too this will give you the opportunity to check for any piston top / cylinder head surface damage etc which is kind of rare depending on the force of the impact ..But first if the belt was found to be running out of alignment - then this could be due to any one of the pulleys the belt runs round inc:- the belt tensioner / guide pulley / Engine oil pump / High pressure Fuel Injection pump / camshaft / crank etc.. running out of line causing the belt to shift inwards towards the inner cover or outwards towards the outer timing cover- so once the covers are off then you need to verify if thats the case by checking each pulley the belt goes around for excess play/movement - once the all pulleys have been check and the guide/tensioner replaced then this shouldn't happen again really unless it been improperly fitted - as far as the above items you had done on it already then none of these really effect the timing belt.the water pump is separate and runs off the auxiliary belt but is one the same side,so it would be worth if not already done to just re-check these things anyway..so ideally first before you do any tests - it would be worth removing the timing cover and see if you can spot anything that may of caused the belt to rub away like that...Also a leaky high pressure fuel pump wouldn't really cause this more continual starting and running issues than anything else unless there is catastrophic failure....
Thanks for the information. After replacing the timing belt, the engine was able to start fine without any problem. However, the mechanics mentioned that there might be engine damage due to louder than usual noise coming from the engine. Assuming the noise comes from damage valves, what would be the estimated cost to replace the valves (parts and labor) in your country in US dollar? Is it likely that the noise comes from damage valves?
Ok..if the engine was able to start then you may of been quite lucky - although its is always best to to consider having a compression test done on the engine once its up and running - as this will confirm wither there is any slight damage or not - if they have the equipment they could do a cylinder leak down test - Without actually hearing for sure then it a vague possibility you may have slight damage - only carrying out the tests above will confirm that if you don't want to go straight ahead and whip the head off to check for any damage - the book time to do that and strip the head is roughly 10 -11 hrs labor time so it not going to be small job they may take a day or so to that - so if you know your garage labour rate per hour which i assume you will based on the timing belt replacement then you'll have idea based on the book time how much your going to be looking at to get this done,ight be worth phoning around for a few quotes once the tests have confirmed - you will also need a new gasket set inc the head gasket and too new cylinder head bolts - costs on average you maybe looking at $850-$900approx
The Opel van is now fitted with a new timing belt, and the engine can be started without problem. Is it ok to drive around the van without looking into the engine? What would be the problem or consequence if there is engine damage, and how it would affect driving?
Yep as mentioned before you can "sometimes" get away with it out any damage .which maybe by the sounds of you have,but the rattle you hear maybe a concern you'll need to keep an eye on in future or maybe have that traced down . but as mentioned before it is always best to double check the compressions are even across all cylinders if at anytime the belt has broken before hand..this will ensure that all valves are sealing properly and don't have any slight damage which may cause loss of compression..so if at all possible maybe have the compressions checked bearing in mind the glowplug removal as mentioned before..eventually if there is any damage then you may have starting issues/loss of power or performance or that rattle you hear becomes louder..however if you feel the the van seems to perform well as it did before then it should very much be ok to drive...
Thanks for your answers. Yes, I did test drive ok today. The power and starting seems to be normal. If the engine has "tha...tha..tha" sound, not sure whether it is normal or not for Opel combo 1.7 as I never did pay attention to engine sound before. What do you think? Anything I should look into more closely?
The technician mentioned that the fuel pump (diesel fuel) might be an issue as it is leaky, and the leaked fuel can damage the timing belt (like melting away the timing belt component?!).Is it true? How do you check for leaky fuel pump?
I am curious whether Opel Combo 1.7 has any built-in engine protecting mechanism to protect engine when timing belt is damage?
The best thing you can do is to try and listen and trace the noise down.i know that can be difficult in some cases but usually doing that can sort of help pin point it to a certain location on the engine..If the noise wasn't there before hand even with the other jobs done then it may well be best to just double check around the engine things have been put back properly - maybe check around the intake system/exhaust system manifold/turbo system for gas leaks /intake pipe work/vacuum tubes etc down the belt side of the engine or listen over the top of the engine.or better still if your mechanic that did the timing belt see if he can listen to it .that maybe the best step forward...but if you feel the engine seems to perform well then it might be worth just leaving it that and just keep monitoring it from now on ie:- checking fluids etc within the engine bay etc etc.
As regards to your diesel leak then in a sense it can effect the belt over time - there maybe vague change it may of been contributory factor to the fault if fuel was getting on the belt which you would notice straight away as diesel doesn't evaporate as fast as petrol and you would see traces of fuel inside the T cover more or less around the bottom - but as you say above before if rubbing on one side then it must of been an belt alignment issue - so again its really a trace job to find out where this leaks from on the pump itself as it could a seal or one of the unions on the pump are slightly loose/leaking or the return lines from the pump etc...As far as my info goes the engine is classed as an interference engine so there is the "possibility" of valve to piston contact - but as mentioned before sometimes you may simply get away with it..but its always best just to verify the every things ok in regards to the valves by doing a compression check or leak down test..