Cam Belt

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Discussion

arium

Original Poster:

101 posts

248 months

Saturday 21st October 2006
quotequote all
Hopefully someone can shed some light on this for me.

My 1989 Esprit has been garaged the past month or so and hasn't been started. The temperature outside has definately changed from summer to fall and there is a nip in the air. I started the Esprit. Fired right up but sounded like crap. Like an ignition miss plus the sound of almost like sparks jumping. Wasn't tho; twas the timing belt flapping away. Do these things suddenly just get that loose?

The belt was done about three years ago along with the tensioner. Am I to assume thats it's time for another go around? I'll check the tensioner first to make sure all rolls smooth and retighten the belt (Checking cam timing of course). I am just concerned that it would suddenly go slack and make that sort of sound in the dead of a deep sleep.

Steve

jk1

469 posts

259 months

Saturday 21st October 2006
quotequote all
More than likely it was loose to begin with or a problem with the tensioner made evident by the cooler temps and inactivity. Sounds like it skipped a belt tooth when it was started.

You're on the right track, check the tensioner and adjust the belt before starting again.

arium

Original Poster:

101 posts

248 months

Saturday 21st October 2006
quotequote all
Many thanks for the advice Jim.

After a couple frustrating hours of pulling the plenum, alternator and triangular brace the problem presents itself; a loose locknut on the eccentric. Luckily the belt had not jumped any teeth and no other damage was done so after retensioning and a nice snugging up all is well again.

In hindsight I should accept some responsibility for what could have been a very bad day. I had an independant shop do the clutch, water pump, timing belt and tensioner when I got the car three years ago. My first clue as to their competence revealed itself a few months later when the exhaust almost fell off becuase the muffler hadn't been snugged up. The vacuum pump did indeed fall off because the pivot bolt fell out and the mounting bracket then broke. That caused a wee bit of an overheating problem as the water pump was no longer being driven. Now this. I should have had everything checked after the first couple things shook loose. I now wonder when the clutch plans to grenade or whatever other demons may lurk in there.

Otherwise she purrs like a kitten now.

Steve

jk1

469 posts

259 months

Sunday 22nd October 2006
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Great! Glad to hear no damage and problem solved.

B16 RFF

883 posts

272 months

Sunday 22nd October 2006
quotequote all
A loose locking bolt is a known problem with the eccentric type of tensioner.
There are two positions of the eccentric that will give the correct belt tension. In one, the belt tension will act to tighten the bolt, and in the other position it will act to loosen it. Obviously, the second is to be avoided, and I would guess this is what probably caused your belt to slacken.

Lotus even put out a service bulletin about it.
I made the same mistake when I changed the belt on my Excel. Luckily the mechanic at the dealer where I took it for the tension to be checked, spotted it.

Paul.