The motor has fuel and compression...

G

GrimnoroftheNorthernLands

Low Mileage
It doesn't have spark.
When the car died, I had just finished some very spirited driving.
I went up a sharp, short incline and lost spark.
I initially thought that it was due to some electrical bit somewhere going out, but upon having a friend turn the motor over while I was looking at it I found that the timing belt wasn't moving. The timing belt is in ok shape, its not brand new but is didn't fail.
When I crank the motor, the engine is turning and has compression in all cylinders, but the crank is not turning the associated pulley.
This happened yesterday, I would be outside still trying to figure this one out if not for the high winds and sub-freezing temperature... and the snow.
Its a 1980 with the 1500cc carbed with the 5 speed and 130,000miles
Thoughts from the experts?
 
The belt has lost its teeth from around the lower crank gear, hence the aux shaft (and distributor) and camshaft are not turning ... hence no spark and no go.

Fortunately it's not an interference engine, and you shouldn't have bent any valves in the process... a new timing belt and you should be good to go... but cam/aux and crank gears, seals and tensioner bearing might also be required depending on their condition.

Teeth stripping off the belt at the crank gear is most likely place for it to happen as this is the tightest turn the belt makes.

SteveC
 
Thank you! I will get a good look at that tonight.
Trolling this forum for information turned up this fantastic link to an epic picasa album: http://picasaweb.google.com/tractor...mingBeltAndTimingSettings#5364733533800782802

I can see how, during the application of torgue to that belt, it might strip it! Hopefully the sun will come out today and I wont have to push the car uphill by myself into my garage. Whatever must be done, must be done though.
 
Impossible?

Isn't it impossible for the crankshaft to remain motionless and have compression in all cylinders? :huh:
 
The crank is turning...

budgetzagato said:
Isn't it impossible for the crankshaft to remain motionless and have compression in all cylinders? :huh:
Click to expand...

If the engine sounds like it is turning over, at least the lower half is in motion. The starter connects to the flywheel which connects to the crank.

I think what was being said was that the cogs on the belt (or the cogs on the crank gear) are stripped, therefore the crank is turning but the cam is not.

That being said, the question becomes, "is it possible to have compression on all 4 when some of the valves are hung open?"

Pete
 
I figured that he meant something like... "with the spark plugs removed I can feel air being pushed out the hole"... or "it's not totally free spinning" - which you would get if you had an interference engine and bent all the exhaust valves from shredding the belt - with the compression on all cylinders bit... because as you so rightly point out, theres no way for all four cylinders to be "compressing" if some valves remain open because the cam isn't turning.

Either way fitting a new belt and seeing what happens is always what you would try first up...

SteveC
 
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