URGENT ADVICE - Cambelt broke

Hi People,

I have damaged my car's engine on the way to work and by the sounds of it, it was the cambelt which broke :down: . At the time i would say i was not doing mo more than 25 Mph but it does kind of worry me about the extent of the
damage. I have been told that the valves maybe bent, head needs to be skimmed and in some cases pistons can get damaged. Its done 84K miles and i used it as a long distance runner for a yr and 5 months (450 miles/week) and
it has never ever given a glitch of a problem. i would preferbly like to see if it can be repaired but i have been told it will cost around £300 to £400 and the car is not worth a lot. The mechanic told me that the head which contains the valves needs to be sent of for testing and the results of that will tell them if the valves need changing.

i opened the top head and saw that two of the levers that push the valves down are broken or snapped but i looked closely at the valves inside the springs and i could not notice if the valves were bent. From what i
could see they looked straight. one thing i noticed was that the values were all in a up position when you would expect to see one up and one down (if you know what i mean). One guy looked at it and said the cam drive is twisted. I wanted to ask a set of questions for those who have had this problem or very experienced mechanics

1. what is skimming the head, is it cleaning the inside?
2. what are the chances of the valves getting bent at the low speed?
3. what are the chances of the pistons getting damaged and affecting the pressure build up in the cylinder or
performance?

i don't mind doing the odd mechanical repairs around the car but i feel the engine needs a proper pair of hands to look at it.

Your help and advice is kindly appreciated.

Thanks

Mani
 
sorry to hear that mate;

in answer to your questions

1.skimming is basically shaving a thin layer off the head to ensure its flat, need to be as flat as poss to allow the head gasket to seal propely.
2. very high, if you didn't bend a valve it would be a miracle
3. again if the pistons arnt damaged I'd be surprised but you may be lucky check for scratches or dinks in the piston before putting it all back togther.

id advise to change then engine though mate, it would be cheaper and you'd have less problems to deal with. they only cost around £100-200 for recon or low milage ones, or as little as £40 from a scrapyard if you can find a nice low millage one.
 
You need to compleatly rebuild the head. Its a CERTAINTY that valves will be bent, the pistons are more likely to be ok than damaged. I wouldnt bother with rebuilding the head, I would proably just get another. It will definately be quicker and cheaper. removing a head does not take long (1hr)

Ed
 
thanks for the replies.

To be honest my dad did say get it changed every 50k miles but i didn't think it was serious. on top of this we were moving houses and my mum passed away recently, things are going down from there on.

i think my dad would prefer to get another car rather then spend money on this as its not worth much. its a shame its come to this as i was becoming a big fan of these micra cars due to its reliability and its ability, as a 1 litr, to pick speed so quickly when using the gears to its full. Also enjoy the fact that people put bets that give it 3 months and it won't last that long due to distance travelled and it would outlast that as well (well i didn't win anything, wish i did).
 
The belt snapping is unfortunate, but it's a wear & tear part. If you were to change the head, you'd still have the extremely reliable engine under there. A newer car doesn't necessarily mean trouble free motoring, i think if your getting attached to the car, your best off changing the engine over and keep it! Probably cheaper than a replacement car too.
 
after i drive the 45 miles to work i checked the oil by taking the lid off and there are signs of slight smoke coming out. i wouldn't say it would be capable of giving off red indian smoke signals but only slight. would you reckon the engine is giving up? if i do go ahead and get a complete head then how much am i looking at. The nearest scrapies around me are one in sparkhill and alumrock so i would assume there are guys there to rip me off.
 
Hi All,

As i had mentioned the cam belt broke. I got the engine looked over by an mechanic. He took the cover off and says the valves are ok but he didn't take the head off. He said if they were bent then one would be lower than the other and would not rise to its normal level. i took the cam followers off and all the valves personally looked ok as they all up in a straight line. Its a long shot but to give a try i bought the cambelt and tensioner, adjusted the cam and crank shaft to the marks and put them in. As i took the cam followers off i was told and read in the haynes that the gap between the points and valves needs to be adjusted (called templets or something similar) using a filler guage so i did that as well (9 thou on cold engine). So i started the engine, took time, as it did before and it started but the sound is not the same, it also vibrates a lot and it does not hold its' idle revs. Took it for a small drive not far and very little pick up. I have been told that if the valves were bent then it never have started. I was told to do a strobe light check which involves moving the distributor mechanism.

Has anyone had this vibrating problem before or knows what is causing it? i was thinking of re-checking the belt maybe i missed a teeth off the alignment as i put it on?

thanks


Mani
 
You have not done what was advised above. There will be bent valves, experience here says you can almost guarantee it.

Your next step if your insistant that the valves are fine, is a compression test. Do that BEFORE you waste any more time ignoring the real problem.

Ed
 
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